Thursday, March 31, 2011

Mad Woman

I call back about the job, after waiting a day. I get voice mail and leave a message. I wonder if we're going to enter a passive-aggressive battle over this.

I look through what is available on Netflix. The Canadian selection is really terrible, because we have different copyright laws than the US, and the content providers are afraid to let Netflix licence their shows in Canada. Most of the "movies I'd like to see" list is not available, and it suggests some laughable substitutes when I search for them. It does turn up some suggestions I like, but they are movies I already own. I start watching the TV series Mad Men, because I've heard some good things about it.

It's a meticulously crafted period piece about the 1960s, and not the Vietnam War or the flower children, but the buttoned down conservatives of the era, at an ad agency. They have a lot of fun with establishing identifiable, fairly timeless situations and then smashing the viewer upside the head with anachronisms we weren't expecting, like when they get up from a picnic and just leave all their trash behind. I keep wondering whether it's a clever social commentary or just an an excuse to produce misogynist, racist television, glorifying old fashioned attitudes. Its redeeming feature is perhaps that it will remind some people that the good old days never really were, and by removing the role of advertising to another era, perhaps show people how easy it is to be manipulated.

But the weird thing about psychological manipulation is that it often works even when you're aware it's happening. Just watching this darn show makes me want to mix an old-fashioned martini. If I watch another season I may get the urge to vacuum in pearls and high heels and bake a meatloaf for some man. If you watch people doing something, even if it's only fiction, even if you don't approve, it makes it more likely that you'll accept that behaviour as normal. That's why the conservative right objects to gay couples being treated unblinkingly as normal human beings on television, why my wacky relative (please tell me everyone has one) believes that shows about friendly space aliens are Hollywood grooming us for when the aliens come to help us, and why some parents don't let their kids play violent video games. Or maybe those parents just want their kids to stop playing video games and help make dinner.

Those of you who read comments will remember the calorie counter discussion from a couple of weeks ago, but I wanted to tell the non-comment-reading people about this too. If you like to keep an eye on weight, fitness and nutrition all in one little app, I recommend myfitnesspal. You don't even need an iPhone/iPad Touch to use it, because it has a web interface too. You may not be into counting calories, or eat weird stuff that is never in calorie look up tables, but this app has almost everything I've eaten in a month, and allows me to specify the ingredients in a recipe or just tell it the caloric value, if I know. It lets you log exercise, and automatically adjusts your remaining calories for the day. It didn't have "plumbing" as an exercise, but it had automobile maintenance, which was about the same level of physical activity. Its strength is that it is completely effortless to use. You just have to resist the temptation to round out your caloric allocation for the day with a few tablespoons of chocolate chips. They're high in iron, I justify.

The water still comes out of my tap really straight, and that potential employer doesn't return my call. Plus it's apparently open season on B737s in North Carolina. Would you have found it on your preflight walkaround? If they hadn't found the bullet on board I might have believed it had been there a while. The airplane would probably have pressurized without a problem. The Screaming Whippet groundschool instructor described an incident where he did a flight, warm and happy up in the flight levels, only to discover after landing at destination that an entire window had blown out right after take-off. It had accidentally been left unsecured after routine maintenance.

Wednesday, March 30, 2011

Getting Things Flowing

I received a phone message regarding another job I applied to. Odd, as I applied maybe two months ago, and it wasn't a large company. Why the long delay? Does the guy plan that far ahead for his employment needs? Did the first two candidates not work out? I'm glad I was out getting plumbing supplies and didn't have to field that one cold. It's a job that could be interesting and right for me, given certain constraints, but it could be a backwards step that would look bad on my resume. I had a list of questions to ask about it by the phone for a while after applying. In fact I just threw my notes on that out the other day.

If the potential employer took two months to think about it, I can take a day. For now the plumbing issue is more pressing. I have already replaced the ball and washers, but the old tap has rotted inside and spews water all over the counter when I turn it on. Under the sink the associated plumbing is crazier than the wiring on a thirty-year-old airplane. It's a mismatched mess of PVC and copper with shutoff valves I run into some difficulty removing the old tap. There should be a nut holding it on underneath the sink, but I can't find it. It's very difficult to see or get any purchase under there because this is a double kitchen sink installed very close to the back wall of the cabinet, so everything is hidden in the sink's cleavage. I do some internet research, trying to figure out if there is an alternate way this might be fastened in, and rein in my urge to just shred it into bits and tear out the bits. There are old copper lines coming directly off the underside of the faucet assembly, and I've already destroyed them looking for what is holding it in place. Besides rust.

Delta, the faucet manufacturer has a toll-free line, so I call for advice. The rep is excellent, listening, understanding, suggesting, then putting me on hold to consult with an expert on older models. He comes back and asks if I have any need to reuse the old faucet. Hell no. He doesn't come right out and tell me to remove the sucker by any means necessary, but I got the idea. The sink is stainless steel and I do need to keep that, preferably untorn, so I destroy the old faucet with tinsnips and a big pair of vice grips so that I can pull its shredded remnants down through the hole in the counter. The new tap goes in easily and the water comes out of it in an attractively coherent stream. When you have done work involving open plumbing lines you need to open the tap up and then turn on the water from below and let it run to flush out any junk from the lines before operating the faucet mechanism. I probably would have run it for a while even if I didn't know that, just to watch the pretty water coming out into the sink and not onto the counter.

And then I signed up with a free trial with Netflix. If I'm going to be off work I might as well get free movies. It's also a way of ensuring I won't get to use it. I should sign up for a gym membership and enroll in a CPR renewal class, too. Every time I do either of those things I have to move halfway across the country for a new job.

And still on the topic of stopped up plumbing, here's a nice job of handling a recalcitrant nosewheel. It looks like a combination of a firm landing on the mains and slowing down enough to reduce airflow pressure was enough to get the nosewheel down and locked.

Tuesday, March 29, 2011

Not Being a Chicken

The Statistics Canada people called back to follow up on my employment status. Did I work in the last 30 days? Well, yes and no. I got a job offer. I went somewhere on my employer's dime and I worked hard at learning things, but I didn't get paid and I didn't get a job out of it, so no. I just tell them the story and let the interviewer encode it the way they want. He probably had a training course on it, and everything. I was looking forward to being a positive datum in the survey. I redouble my efforts to make that happen next month.

I hate online application forms that require me to enter "expected salary" and won't let you go to the next page without it. At least with a paper one you can enter a range or write something vague. Some of the ones I've hit lately ones verify that I enter one proper number. I apply to a couple of jobs at my current level, jobs I should be able to get, but not jobs that advance my career.

The phone rings, I answer with my name. The person actually listens to what I said, then uses my name as he asks to speak to someone else, a male name. There's no one by that name who lives here. I tell him that and he thanks me and hangs up. I psych myself into believing that he bailed because he didn't like the way I sound. I try to knock myself out of that headspace to in order to write sincere, enthusiastic cover letters.

When I run spellcheck on what I've got and it complains about my e-mail address, the non-blog e-mail on my resume, not the cockpitconversation one. It suggests I replace it with one of:


If you can reverse engineer that, send me an e-mail!

I make a note of that for the blog, then read some e-mail and write an unrelated blog entry. Now what was I doing? Oh yeah, I was revising my resume.

I didn't apply for a job in Yorkton. Nor to another one in the north, posted by an employer who doesn't know the difference between the shift and the caps lock key, for a company that ten years ago had a 'don't bother applying' reputation where women were concerned. The guy probably thinks ovaries interfere with the operation of the rudder pedals. You can picture him, in a tractor hat, typing with two fingers and a pained expression on his face. He can skin a moose, load it into a plane, fly bush IFR and finish off a mickey of rye on the way home. Be assured I'm not implying anything about the particular operator. I don't know him, and for all I know the shift-key-challenged person is a twenty-five year old female. It just amuses me to construct a picture of the boss I'm not applying to serve. The job is in a town where I really don't want to live, and I don't have the particular time they favour, anyway.

Actually, I always summon up a picture of the person I'm writing to. Sometimes I know what they look like, and I usually know what their airport and hangar look like. I imagine them reading my e-mail and looking at my resume and being pleased with what they see. I also picture myself there. I'm not doing it as some kind of New Age visualization process, it's just what I happen to do. I commit to things.

It's irritating the number of little changes I made in my life because I thought I had a new job, and now I have to undo them, or just feel their reminder all the time. They were tiny things like changing the default airports and towns I see the weather for when I check my iPod touch, and rearranging my sock drawer to make it easier to grab the black ones when I get dressed in the morning. The black ones used to be at the bottom, or permanently in my suitcase. I did a bunch of menu planning and associated grocery shopping to make flight bag lunches, so I have to use that up, and kick myself every time. It's also harder to settle down and apply to okay jobs when I can still taste the fine one that got away.

Monday, March 28, 2011

Actual Quotes from Company Manuals

My all time favourite advice from a company manual is from a chapter that after explaining how to tear out the electrical wiring to make snares to catch rabbits, notes that you will get sick if you eat nothing but rabbits for a week. I've mentioned that one before, but I have a few more gems to share with you.

"Pilots must use their best judgment in dealing with life threatening situations."

Those were from the section on dealing with hijackers. I WISH I had the lack of scruples to quote you the hijack bomb threat instructions because they are hilarious. I am now convinced that airline pilots affect the solemn, noble "I'm sorry I can't tell you that for security reasons" demeanour on this subject because they would be embarrassed to admit the ridiculous advice their company gives them to deal with a whacko with a gun to their head. You might be better off to read the hijacker the manual and hope he keels over laughing.

"In the event of a forced landing, if time permits, it would be advisable to anticipate possible injuries (especially head trauma and broken ankles) to one or both pilots and have an evacuation plan."

So after you've run all the checklists, you turn to the pilot in the other seat and say, "In the four minutes before we hit the ground, I'd like to make a pact with you that if one of us is conscious and capable of locomotion while the other isn't that we'll drag each other's asses out of the burning plane, okay?" Or does it go more like "Anticipating head trauma and broken ankles, lets skip movie night on Tuesday, k?" Maybe someone with more CRM experience can give me a heads up on how that conversation goes.

Elsewhere I'm advised that in the event of complete loss of pitot-static information, I should fly pitch and power. That's easy to say, but in IMC it would be extremely difficult. It's not something a person gets a lot of opportunity to practice.

Sunday, March 27, 2011


Every time you start work at a new company, you have to learn their SOPs--standard operating procedures. In a two-crew environment. Most of that is not so much what you do but what you say while you are doing it. There is a very specific vocabulary and grammar and specific phraseology for each situation you might encounter. This is intended to be absolutely standardized across the company, but is not standardized between companies. That would be impossible to completely standardize because of differences in aircraft and operations, but it could be largely so, saving work not only for pilots, but for the management who have to write the manuals tells us exactly what to say.

Let's say an engine fails. The first pilot to notice it, probably the flying pilot says something like ...

"Confirm number one failed."

"Engine failure, left engine."

"Left engine failed. Confirm."

The other pilot confirms the failure with language that probably echoes the wording of the first call, then they launch into the memory items of the engine failure checklist. Typically, in a propeller-driven aircraft, the steps are to feather the correct propeller, shut off the fuel for the failed engine in a couple of places and finish securing it from the written checklist. But because shutting down the wrong engine in an emergency is a highly reliable way of killing yourself, there's usually a whole litany of confirming before anything gets turned off.

The litany above might continue ...

FP: secure left engine

NFP: left throttle, confirm

FP: Confirmed. Close.

NFP: Left propeller, confirm.

FP: Confirmed. Feather.

NFP: Left fuel shutoff, confirm.

FP: Confirm. Close.

And so on. Somewhere in here is a tipping point where the procedure becomes so unwieldy that either it distracts the pilots from flying a seriously underpowered and lopsided airplane in an emergency situation OR the captain gets fed up with it and just shuts the damned engine down as she would have single pilot, thereby bypassing all the safety the procedure was designed to provide. Both are real risks. On the groundschool course that I recently had the privilege to attend free of charge with no obligation, I had the opportunity to witness the conception of a monster as one of the instructors noticed that an SOP involving selecting bleed air off in response to a duct overheat light did not have the identify/confirm step in it. I think I managed to avoid screaming "no! no!" (or maybe that's why they didn't invite me to continue with the programme) but I thought it. It's just bleed air. If the wrong one is selected off, an SOP such as "oops, other left" or "why don't you turn them both off until you get a chance to see which shoe the 'L' is written on?" isn't going to kill you. The management pilot concerned might argue that having a full on confirmation protocol won't kill me either, but it's sad when your SOPs aren't sleek and elegant.

You end up with something like this.

Saturday, March 26, 2011

Escape Route

For all the praise lavished on the DHC-2 Beaver, I don't think anyone has ever called it ergonomic. They were designed back when you were supposed to be a real man in order to fly an a airplane and if you couldn't cope with the fact that the levers weren't in the standard order on the throttle quadrant (as they were on one I flew) then you weren't man enough. I can't remember if it was the throttle and prop, prop and mixture or mixture and throttle that were switched, and the fact that I don't remember perhaps illustrates the problem. Imagine if one of the cars you drove had the accelerator and brake pedal switched. Or maybe the accelerator and clutch. It wasn't the designer's fault in those days.

One of the problems with Beavers has been the door handle. It was designed to close securely, and probably was cool and modern, or at least normal in 1947, but twenty-first century passengers have grown accustomed to a different style and standard of exit door from a vehicle, and have not found it to be an intuitive escape route. Deaths in otherwise survivable accidents have led to a redesign of the door handle, something that is a little unusual in an out of production aircraft, but they are still so popular that a different manufacturer has the licence to make parts for them and has taken on the responsibility of the replacement door handle.

Also: The TSB recommended floatplane passengers wear lifejackets but the airlines object. They say it's because passengers might inflate the jackets inside the airplane, hampering their escape. That's a true risk, and has caused fatalities in water landings, but I personally think there is at least as much, if not more, risk of a passenger inflating a lifejacket inside an aircraft if they have just put it on than if they are already wearing it. And there is certainly more risk of not having a lifejacket on when you need it if you have to put it on in the time period between realizing there is a problem and escaping the aircraft. I was once present when a large floatplane dug a wingtip into the water during landing, and the only person who got the lifejacket out from under his seat during the crucial seconds before the airplane fortunately didn't require an emergency evacuation, was a jumpseating captain. The real reasons the airlines don't want to put lifejackets on passengers before every departure are time, cost and did you see Six Days Seven Nights? Notice that despite all the commercial seaplane flights depicted being in the same type with the same pilot, the only flight in which the pilot required the passengers to wear lifejackets was the one in which the premise required them to be nervous and seem ridiculous.

Friday, March 25, 2011

Some Backstory

Do you play video games? Sometimes while I am playing video games I realize a moment too late what move I should make and then make that move anyway. So I shoot the wall, instead of the enemy, wasting ammunition. I jump after the door has closed, and slam into the wall. I turn around right after the Pac-Man ghost stops being blue. It's not slow reflexes, it's more of a "no! I meant to do this!" It's the action of a pilot who moves the gear lever to the "extend" position after landing gear up.

I'm wondering to what extent I do that in my career. There are jobs I would have killed for years ago that I shouldn't take now, but the instinct is that I still want them. What should I aim for? Do I have enough power dots left on this level to try and lure the ghosts to me, or should I just sneak around and get all the little dots to get through without dying?

A few weeks ago I realized I was sending out job applications without much of a plan, or a really clear idea of what it was reasonable for me to expect to achieve. I needed some help sorting out my career. I needed someone who knew me, who knew the various aspects of aviation in which I have participated, and who had realistic knowledge of the Canadian aviation scene. I know a number of wonderful people The name of the right person came to me one morning and when I e-mailed him, I discovered that he had moved back to my part of the country since I'd seen him last, so his home was only a couple of hours drive away. And he was happy to counsel me, declining my offer to pay for his time.

I brought my logbooks, my resumé, and a big box of kleenex, but I'm proud to say that I didn't burst into tears the whole time. He listened, he nodded, he told me my aspirations were not unreasonable for my age and experience and then as a bonus he rattled off a list of potential employers along with inside information on their hiring. It was encouraging and enjoyable, and I kind of wish I had built on that in a more stable fashion, but the next day I received the job offer that launched the most recent round of Aviatrix rides the roller coaster.

I'll go back to reading manuals at you in a few days, no doubt. Or I'll get a job and move across the country and you won't hear a thing for weeks.

Sarah linked to the above picture yesterday in a comment and it made me laugh so hard I had to share it. What is that eagle doing? Is the image upside-down?

Thursday, March 24, 2011

And Another One

Okay that whole "keep the early morning momentum going" thing didn't work out too well. I don't think they will call back. If they liked me and were as busy as they clearly were, they would have trained an extra captain to get ahead of the curve. I'm back to the mode of no great thing in sight, so why should I do anything now. The place was littered with study materials, abandoned after the news that my new familiarity with the Screaming Whippet wasn't going to help anyone, and their presence wasn't improving my mood any. I wanted to put them in a pile and burn them, along with my licence, but sense prevailed. Besides, hey, free books! I put them away, with a huge pile of other manuals of airplanes I have flown, wished I'd flown, had friends that have flown or just acquired because it seemed cool at the time.

I checked into that whole chicken thing. My municipality has a whole packet of rules about chickens. There isn't enough room to accommodate the chickens here, not with following all the rules about the amount of indoor and outdoor space and the chicken jacuzzis and the distance from all dwellings they have to be. I'm also not allowed to hatch my own chickens, because both baby chicks and male chickens are illegal. The truth is, I probably didn't want to do that much work anyway. Chickens need a lot of looking after. How does anyone ever decide to have children? Chickens are nothing compared to kids, and if you're really fed up with them you can take them to an abattoir and then bring them home for dinner. So that means I'm apparently not properly equipped to care for a chicken. Yet they let me fly. It would be cool if they required you to get a licence and prove that you had the proper amount of space, and gave you a list of the required tasks and how much time they would all take before you were allowed to have children.

So no chickens. Maybe a rat. Do I qualify for a rat licence? It would probably bite me, anyway. Stupid rats.

I think I'll pull some of the more interesting airplane manuals out and make the groundschool thing a regular feature here. I'm going to read airplane manuals and translate them into basic silly English on the blog. But it seems like every time things go well, but the time I post blog entries about them going well, they've gone bad again. So I'm never going to tell you I have a job ever again. I'm just going to post random aircraft systems and make up stories about me flying airplanes. You'll never know if they are true or not. Maybe I've been making this all up all along.




But warm. I almost gave my old company jacket to charity last week, in anticipation of getting a new one. In that respect, if I were more organized, I'd be cold now.

Wednesday, March 23, 2011

Another Day

Now I'm feeling madder than yesterday. They aren't going to call me back. I'm in some kind of No Fly database that I can never know about or escape from. Once when I left one job for a better one, the owner of the old company called the manager of the new company to say that I was a terrible pilot and a non-trustworthy employee. Fortunately the new boss already knew me, so realized that the last desperate ploy to stop me getting the new job was actually a compliment about my value as a pilot. Sometimes I picture a vast conspiracy wherein that boss has made it his life's work to sabotage my career, finding out wherever I try to go and poisoning them against me. Hey, some of you thought it was paranoia last week when I had the premonition this job was going to fall apart.

But for now, I'm just fed up. I hate airplanes. They're stupid. I'm going to go buy some chickens and look feed them and collect the eggs. No, I'm going to rent an incubator and buy some fertilized eggs and hatch my own chickens so they imprint on me and I can raise them and train them to fetch, or cluck on command, or not to drown in the rain, or whatever the pinnacle of chicken learning is. And then I'll collect the eggs, and then when the chickens stop laying eggs I will tell them that I have rescinded their job offer, and I will eat them. And yay for the circle of life.

I found a big pile of partially completed to do lists today; I never throw out uncompleted to do lists, it seems, just abandon them half done. And they all seem to have the same things undone, things that always need doing even though I do them fairly often, things that come around again and again. I'm going to do them all. I'm going to go through all my lists and do them until they are done once and for all, and not have any fun because I don't deserve any. Except that feeding my chickens might be fun. I'll let you know.

I turn on my computer to find out where to buy chickens and somehow end up on an aviation job site. I haven't checked it for a week, on account of thinking I had a job. "Hmm, this job looks good." I could raise chickens there instead of here. I start to compose an e-mail to the chief pilot, when the phone rings. It's an ex-chief pilot, in town flying a medevac to here. I go out to dinner with the crew, good to catch up. One of the flight medics observes, "I never knew before this job how difficult it was to be a pilot." I thought she was talking about physical tasks like loading, de-icing, or the hours, but she continues to say, "You can't just decide where you want to work, apply and get a job. You have to work really hard to find a job, and go wherever that job is." She gets it. And it's not just me. It's the industry. I come home and finish the e-mail. And send another to another company. And make a list of more people to contact. Life goes on.

I hate airplanes. At least when chickens shit on you, you can use it to fertilize the garden. I think the worst part is that I know every fricking circuit breaker on this airplane I'll probably never fly. All those brain cells faithfully holding information that I may never use. Who wants me to finish telling you all about the airplane for which I received free groundschool and training manuals, and who wants to skip it and learn about chickens?

Tuesday, March 22, 2011

Do Not Pass Go. Like Ever.

They rescinded the job offer. It's not my personal hygiene, but the usual thing in aviation: they had a number of captains interviewing with bigger companies and expected to lose more than they lost. So they don't need everyone in the class. Specifically, they don't need me. My paranoia was correct. The chief pilot bounced my e-mail over to HR and the HR person called promptly to deliver the bad news.

The company was completely professional throughout. They sent me all the right documents, flew me to the training base, put me up in a good hotel, provided a car for our use, and treated us with respect. It's possible that they intended all along to only train their favourites from the class. Maybe I said or did something they didn't like. The ones who were trained were younger than me, but had more turbine and more two-crew SOP experience. It's the same thing at every step: you need experience to get experience, whether it's your very first flying job, your first multi job, a two-crew job, a turbine job, a 705 job, a jet job ... whatever you want you can't get it because you don't have it. I just shake my head.

So yeah, sucks. Sorry for leading you on, but well, welcome to my experience. The HR guy had the courtesy to say sorry too.

I've figured it out. I'm expecting my life to be a movie where the protagonist triumphs in the end, but instead it's some sort of weekly sitcom. I can't succeed, because then the story wouldn't make sense in syndication. I have to be forever beaten back, the status quo preserved, every advancement rescinded and reset for next week's episode. It's all I can do to keep from getting cancelled.

I'm surprisingly okay with it. I guess I've stopped believing anything good is ever going to happen, and was so careful not to believe too hard in this, so as not to jinx it, that when it didn't happen I was expecting it. I promise I'm not making this stuff up just to entertain you. This is really the way it works. I don't even think it works worse for me than average. I have met plenty of people in my travels with similarly disastrous career paths. Most of them aren't in aviation anymore.

I was working towards improving my efficiency so I could get everything at home done despite working fourteen hour days. I'd even timeshifted my daily routine to get ready for the early mornings. I'll run with that, be more efficient without having to work 14 hour days. Imagine what I'll get done!

I hadn't had a chance to put in the new bricks that I got from the cow bits guy until today, because it snowed again and covered everything up. Today I could find the garden again so I placed the last bricks. It looks good. I might as well get it to look good before I leave it all behind and go find another job. Maybe I should go on a road trip.

Monday, March 21, 2011

Another Look Through Airplane-Coloured Glasses

As I mentioned before, when world events are so immense that it is hard to take in the enormity, there is a tendency to narrow ones focus to some aspect that is familiar and relate-able, even at the risk of trivializing the real impact. Animal lovers focus on stranded pets. American talk show hosts discuss how the earthquake influences political candidates' polling numbers. And airline geeks look at the effect on the supply of jet fuel.

There are two intertwined issues, production and transportation. Japan, according to the article linked above, produces four percent of the world's kerosene, and about 1.5 million barrels per day production is offline due to the earthquake. This includes the Cosmo Oil refinery at Chiba which caught fire on fire and other refineries shut down for lack of power because of the nuclear reactors being offline. Other refineries in Japan and elsewhere may have the ability to meet the demand by increasing production, but it also has to be transported through a country with a compromised infrastructure.

Initially reports were that Japan had enough fuel for a week, but airline schedules and policies have changed around the disaster. Japan asked airlines to tanker (i.e. carry in the tanks even though it wasn't needed for the flight) fuel coming into Japan to reduce the amount that needed to be taken there. Some companies are no longer overnighting crews in Japan, giving them an additional leg to Seoul or other nearby Asian cities, so they need to take less fuel in Japan. This partial list of airline changes is interesting to me as it shows some companies cancelling or flying less, but some more capacity, or switching to fewer flights but larger airplanes, depending on passenger demands and other needs of the operation.

AEROFLOT Capacity increase on selected Tokyo flight, as well as extra flight on 17MAR11
SU2575 SVO2145 – 1330+1NRT 763 17MAR11
SU2576 NRT1530 – 2050SVO 763 18MAR11

Service on 17MAR11-19MAR11 from SVO, 18MAR11-20MAR11 from NRT, operates with Ilyushin Il96-300 instead of Boeing 767-300

Air Canada Tokyo departure to Toronto and Vancouver operates via Osaka on 18MAR11/19MAR11
AC002 NRT1710 – 1835KIX1935 – 2100YYZ 77W
AC004 NRT1905 – 2040KIX2140 – 1710YVR 333

Air China Selected Tokyo scheduled service CANCELLED until 26MAR11
Beijing – Tokyo Haneda CA183/184 CANCELLED (Reduce to 1 Daily)
Chengdu – Beijing – Tokyo Narita CA421/422 CANCELLED (PEK NRT Reduce to 12 weekly)
Chongqing – Shanghai Pu Dong – Tokyo Narita CA157/158 CANCELLED (PVG NRT Reduce to 2 Daily)

Larger capacity aircraft to be operated on existing Tokyo flights and other local cities in Japan

AIRFRANCE Stop over at Seoul Incheon in both direction extends to 23MAR11 (24MAR11 from NRT)
Paris CDG – Tokyo Narita
AF276 CDG1050 – 0535+1ICN0655+1 – 0935+1NRT 77W 17MAR11-23MAR11
AF278 CDG2100 – 1545+1ICN1705+1 – 1945+1NRT 77W 17MAR11-23MAR11

AF275 NRT1305 – 1540ICN1655 – 2105CDG 77W 18MAR11
AF277 NRT2155 – 0030+1ICN0145+1 – 0555 +1CDG 77W 18MAR11-24MAR11
AF275 NRT1145 – 1420ICN1535 – 1945CDG 77W 19MAR11-24MAR11

Air India Service until 19MAR11 operates at approximately 2hrs later for DEL departure. Boeing 747-400 or 777-300ER operating
Delhi – Tokyo Narita
AI306 DEL2300 – 0950+1NRT 744 18MAR11-19MAR11

Air Tahiti Nui
Papeete – Tokyo Narita service on 18MAR11 (19MAR11 from NRT) Canceled

Alitalia Until 20MAR11, Tokyo Narita service is CANCELLED, these service will operate into Osaka Kansai
Milan Malpensa – Tokyo Narita
AZ786 MXP2155 – 1730+1NRT 772 18MAR11/20MAR11
AZ787 KIX1700 – 2130MXP 772 19MAR11

Rome – Osaka Kansai Extra flights in operation to replace service to Tokyo Narita from 16MAR11 to 19MAR11
AZ782 FCO1555 – 1200+1KIX 772 19MAR11
AZ784 FCO1855 – 1500+1KIX 772 18MAR11/20MAR11

AZ783 KIX1400 – 2005FCO 772 17MAR11
AZ783 KIX1400 – 1845FCO 772 18MAR11/20MAR11
AZ785 KIX1700 – 2145FCO 772 20MAR11
AZ785 KIX1930 – 0015+1FCO 772 18MAR11/19MAR11

ASIANA AIRLINES Extra one Daily flight on Seoul Incheon – Tokyo Narita planned until 22MAR11
OZ1083 ICN0520 – 0730NRT 321 16MAR11-22MAR11
OZ1073 NRT2125 – 2350ICN 321 16MAR11-22MAR11

Austrian Operation from VIE is delayed on 18MAR11 and return on 19MAR11. Return flight operates via Seoul. Schedule after 19MAR11 will be announced pending on latest situation

Japan's refinery woes compared with unrest in Libya and elsewhere in the Middle East is driving up not just jet fuel but ordinary mogas prices. Japan being so technologically advanced and diversified in manufacturing, there is probably no industry unaffected by the events there. I'd be interested in hearing how the earthquake has affected you, even if you're nowhere near Sendai.

Sunday, March 20, 2011

Holding Speeds

In a faster airplane, I suddenly have to start thinking about things that never were an issue in slower ones. Suddenly stuff I skimmed over, like noise abatement rules, advisories to remain below 165 knots in the climb until above a certain altitude and engine-specific rules become relevant. For some reason I loved the 250 and 200 knot speed restrictions when I learned them in private pilot groundschool, but I've never needed to care. Here are the rules from the CARs:

602.32 (1) Subject to subsection (2), no person shall

(a) operate an aircraft at an indicated airspeed of more than 250 knots if the aircraft is below 10,000 feet ASL; or

(b) operate an aircraft at an indicated airspeed of more than 200 knots if the aircraft is below 3,000 feet AGL within 10 nautical miles of a controlled aerodrome unless authorized to do so in an air traffic control clearance.

(2) A person may operate an aircraft at an indicated airspeed greater than the airspeeds referred to in subsection (1) if the aircraft is being operated in accordance with a special flight operations certificate - special aviation event issued pursuant to section 603.02.

(3) If the minimum safe airspeed for the flight configuration of an aircraft is greater than the airspeed referred to in subsection (1), the aircraft shall be operated at the minimum safe airspeed.

602.33 No person shall operate an aircraft at a true Mach number of 1 or greater.

Okay, that last one isn't an issue just yet, but who knows, eh?

It's also the first time I'll be legally required, as opposed to just being sensible, to slow down in a hold.

10.7 Speed Limitations

Holding patterns must be entered and flown at or below the following airspeeds:
(a) Propeller Aircraft (including turboprop)

(i) MHA to 30 000 feet 175 KT IAS

(b) Civil Turbojet

(i) MHA to 14 000 feet 230 KT IAS

(ii) above 14 000 feet 265 KT IAS

(c) Military Turbojet

(i) all except those aircraft listed below 265 KT IAS

(ii) CF-5 310 KT IAS

(iii) CT-114 175 KT IAS

(d) Climbing while in the holding pattern

(i) turboprop aircraft normal climb speed

(ii) jet aircraft 310 KT IAS or less

Minimum Holding Altitude (MHA) – The lowest altitude prescribed for a holding pattern which assures navigational signal coverage, communications and meets obstacle clearance requirements.

I love how all the military section says reduces to, "Look, unless you're a CF-5 Freedom Fighter, you're just a jet. And Snowbirds? You're not really a jet."

So that's holds. Airplanes are so fast, but just when you think you're going somewhere, you find out that you have to slow down and circle back. For the approximately two people who still remember what this post means: yeah, I'm serious.

Saturday, March 19, 2011

Landing During an Earthquake

I have another anonymous, much forwarded piece from a pilot who was operating in Japan during the earthquake. This one is also from a Delta pilot, identified as "J.D." It complements the other, as s/he was landing at the time. Note that if any of the pilots involved in these stories wants to be credited by name or to have the story removed, just let me know. I think they are fascinating examples of the kind of can't-plan-for-it decision making that flying entails. This is edited only in that I removed the part where the writer pointed out the Top Gun reference, because the punctuation involved broke my html, and you guys don't need that sort of thing pointed out for you.

I'm currently still in one piece, writing from my room in the Narita crew hotel. It's 8am. This is my inaugural trans-pacific trip as a brand new, recently checked out, international 767 Captain and it has been interesting, to say the least, so far. I've crossed the Atlantic three times so far so the ocean crossing procedures were familiar.

By the way, stunning scenery flying over the Aleutian Islands. Everything was going fine until 100 miles out from Tokyo and in the descent for arrival. The first indication of any trouble was that Japan air traffic control started putting everyone into holding patterns. At first we thought it was usual congestion on arrival. Then we got a company data link message advising about the earthquake, followed by another stating Narita airport was temporarily closed for inspection and expected to open shortly (the company is always so positive).

From our perspective things were obviously looking a little different. The Japanese controller's anxiety level seemed quite high and he said expect "indefinite" holding time. No one would commit to a time frame on that so I got my copilot and relief pilot busy looking at divert stations and our fuel situation, which, after an ocean crossing is typically low.

It wasn't long, maybe ten minutes, before the first pilots started requesting diversions to other airports. Air Canada, American, United, etc. all reporting minimal fuel situations. I still had enough fuel for 1.5 to 2.0 hours of holding. Needless to say, the diverts started complicating the situation.

Japan air traffic control then announced Narita was closed indefinitely due to damage. Planes immediately started requesting arrivals into Haneada, near Tokyo, a half dozen JAL and western planes got clearance in that direction but then ATC announced Haenada had just closed. Uh oh! Now instead of just holding, we all had to start looking at more distant alternatives like Osaka, or Nagoya.

One bad thing about a large airliner is that you can't just be-pop into any little airport. We generally need lots of runway. With more planes piling in from both east and west, all needing a place to land and several now fuel critical ATC was getting over-whelmed. In the scramble, and without waiting for my fuel to get critical, I got my flight a clearance to head for Nagoya, fuel situation still okay. So far so good. A few minutes into heading that way, I was "ordered" by ATC to reverse course. Nagoya was saturated with traffic and unable to handle more planes (read- airport full). Ditto for Osaka.

With that statement, my situation went instantly from fuel okay, to fuel minimal considering we might have to divert a much farther distance. Multiply my situation by a dozen other aircraft all in the same boat, all making demands requests and threats to ATC for clearances somewhere. Air Canada and then someone else went to "emergency" fuel situation. Planes started to heading for air force bases. The nearest to Tokyo was Yokoda AFB. I threw my hat in the ring for that initially. The answer - Yokoda closed! no more space.

By now it was a three ring circus in the cockpit, my copilot on the radios, me flying and making decisions and the relief copilot buried in the air charts trying to figure out where to go that was within range while data link messages were flying back and forth between us and company dispatch in Atlanta. I picked Misawa AFB at the north end of Honshu island. We could get there with minimal fuel remaining. ATC was happy to get rid of us so we cleared out of the maelstrom of the Tokyo region. We heard ATC try to send planes toward Sendai, a small regional airport on the coast which was later the one I think that got flooded by a tsunami.

Atlanta dispatch then sent us a message asking if we could continue to Chitose airport on the Island of Hokkaido, north of Honshu. Other Delta planes were heading that way. More scrambling in the cockpit - check weather, check charts, check fuel, okay. We could still make it and not be going into a fuel critical situation ... if we had no other fuel delays. As we approached Misawa we got clearance to continue to Chitose. Critical decision thought process. Let's see - trying to help company - plane overflies perfectly good divert airport for one farther away...wonder how that will look in the safety report, if anything goes wrong.

Suddenly ATC comes up and gives us a vector to a fix well short of Chitose and tells us to standby for holding instructions. Nightmare realized. Situation rapidly deteriorating. After initially holding near Tokyo, starting a divert to Nagoya, reversing course back to Tokyo then to re-diverting north toward Misawa, all that happy fuel reserve that I had was vaporizing fast. My subsequent conversation, paraphrased of course...., went something like this:

"Sapparo Control - Delta XX requesting immediate clearance direct to Chitose, minimum fuel, unable hold."

"Negative Ghost-Rider, the Pattern is full"

"Sapparo Control - make that - Delta XX declaring emergency, low fuel, proceeding direct Chitose"

"Roger Delta XX, understood, you are cleared direct to Chitose, contact Chitose approach....etc...."

Enough was enough, I had decided to preempt actually running critically low on fuel while in another indefinite holding pattern, especially after bypassing Misawa, and played my last ace...declaring an emergency. The problem with that is now I have a bit of company paperwork to do but what the heck.

As it was - landed Chitose, safe, with at least 30 minutes of fuel remaining before reaching a "true" fuel emergency situation. That's always a good feeling, being safe. They taxied us off to some remote parking area where we shut down and watched a half dozen or more other airplanes come streaming in. In the end, Delta had two 747s, my 767 and another 767 and a 777 all on the ramp at Chitose. We saw two American airlines planes, a United and two Air Canada as well. Not to mention several extra Al Nippon and Japan Air Lines planes.

Post-script - 9 hours later, Japan air lines finally got around to getting a boarding ladder to the plane where we were able to get off and clear customs. - that however, is another interesting story.

By the way - while writing this - I have felt four additional tremors that shook the hotel slightly - all in 45 minutes.

I can so empathize with the successive feelings of "yep, we're good on fuel ... okay we've got enough fuel ... if anything else happens we won't have enough fuel ... let me get on the ground now! now! now! ... phew we're on the ground with fuel in the tanks." You are always balancing the desire to please the company, ATC and passengers against the desire to land with lots of yummy delicious extra fuel. Pilots think about fuel the way broke people think about money: all the time.

Friday, March 18, 2011

Boarding During an Earthquake

I had this forwarded to me without a name. It's a first hand account by a Delta Airlines captain whose flight was boarding at Narita when the 8.9 earthquake struck off the coast of Japan.

We were at the gate onboard ship 7001 with passenger boarding in progress when the earthquake began. My F/O, Joe Haggerty, had taken his seat and I was standing behind the center radio console when the airplane began shaking. Initially thought it was wind gusts but ruled that out since it had been calm when we left the hotel. Jet blast from a taxiing aircraft? Nope, look, the terminal windows are flexing and the building is...moving! It's an earthquake...immediately, in a brilliant display of airmanship, Joe reached over and set the parking brake. It seemed quite possible that we could jump our wheel chocks and roll into something hard. After a minute of this, the shaking got much worse and lasted about 2 1/2 minutes total. Our passengers intuitively decided that the safest place in all of this was on the aircrart and not in the terminal or the jetway. Never seen 261 people board a 777 so quickly! Two long and impressive aftershocks followed during the next hour. Narita closed it's runways and our inbound flights began diverting. 281 from Atlanta was about 10 minutes from landing and diverted to Nagoya. Hanada and Narita were both closed. They evacuated everyone from the Narita terminals deeming the structures unsafe for occupancy. The Narita tower was evacuated, Narita Approach Control was evacuated. At about 4pm, the airport was notam'd closed "until 0600 tomorrow morning". So, Delta cancelled us and all of the other flights out of Narita.

Well.........there was only one "safe area" established at the airport (outside in a cold rain) where passengers could be taken if they deplaned. It became full. There was no chance of deplaning into the terminal. No chance of deplaning at all. No ground transportation as all busses and trains were shut down and the highways had been closed. So, Delta calls the Narita Airport Authority and suggests that since the runway had been inspected, it might be a real good idea to allow 6 Delta departures and get maybe 1,400 customers out of this mess. They agreed and after a four hour wait at the gate, we got out of there. On departure we could see four distinct, large fires in downtown Tokyo, 50 miles to the south. A refinery was on fire at the coastline to our east. We had no real idea of the size of the disaster until we had a datalink discussion with our dispatcher who filled us in. Now, watching the news at home, I am stunned at the devastation. All Delta crews and employees are safe and uninjured in Japan. I am not sure if the layover hotel has power. I'm glad I'm not in room 932 anymore with the aftershocks that they are getting.

Happy to be home and thanks for your concern.

It's weird when you're on the ground and the airplane is moving in a way you haven't commanded it. I remember the first time I couldn't taxi straight in wind, and can see why that was the captain's first impression.

Thursday, March 17, 2011

Thirty Minutes of Oil

Oil: I'm supposed to put Exxon 2380 oil in this airplane and it goes all around and makes things slippery, cooled, cleaned and sealed. Done. Yeah, right.

C'mon, Aviatrix, it's not that bad. Half an hour on the oil system and then you can go play with your toy flight simulator. Minimum oil temperature for start is -40. You don't need units there, the Fahrenheit and Celsius scales cross at -40. I'd be cross, too. In addition to the standard four functions of oil referenced above, oil pressure on this airplane takes part in propeller operations, specifically normal blade adjustment, negative torque sensing, and the unfeathering pump. It's used in three parts of the anti-icing system, and it has gauges and annunciator lights associated with it.

Oil lubricates the reduction gear, so that the propeller rpm can be 2000 instead of the 42,000-odd rpm of the main engine, and oil pressure in the propeller hub drives the propeller towards fine, against the pressure of the feathering spring, using the usual system of flyweights governing a pilot valve to keep the propeller on speed. Feathering dumps the oil from the hub, allowing the feathering spring to drive the blades all the way to 89%, while negative torque adjusts the blade angle to windmill in the 18-28% range, waiting for the pilot to either feather or attempt a restart. It's a kind of half-hearted autofeather.

Anti-icing has already been described, oil circulates in the oil cooler inlet lip, and then if its temperature is still above 55 degrees it goes to the oil cooler, else it goes through the filter and back to work. Fifty-five is the oil's lucky number because that's also the pressure differential across the oil filter that will cause it to bypass the filter. Oil heat also anti-ices the lower part of the engine air inlet, provides the heat for the fuel anti-icing heat exchanger, and makes the airplane nice and warm if you put your hands against the nacelle after shutdown.

Would you believe that that took me thirty minutes? It did include going off to get another book to look at a diagram of the propeller system. I need to know more than this, but I need a break.

Wednesday, March 16, 2011

Engine Startrekinsey Sequence

I'm not sure if this is a cohesive description of the engine start sequence or an unpublished chapter of Joyce's Ulysses in which we follow Aviatrix's stream of consciousness as she slides into aircraft manual-induced, chocolate-deprived madness. Either way, come for the engines, stay for the Star Trek references and sexual innuendo.

When I start my car, I put my foot on the brake, the key in the ignition, turn and hold the key until the engine sounds just right, then release the key and the engine continues. That's a little bit complex. You have to get a feel for when to release the key. When I first learned to drive there was another complication, in that I had to put my foot on the gas as well and give it just enough gas to start. But many of you start old manual transmission cars every day without even thinking about the process. And some of you start up an electric car by, I understand, pushing a button. I think they just push a button to start the starship Enterprise too, so this is clearly the way of the future.

Push button airplanes exist, and starting mine does begin with pressing a button, but it's a little more complicated than that, and I have to know and understand the whole sequence, including the stuff that does happen automatically. I'm sure I'll be quizzed on this all during the test, and if I'm going to feel helpless someday when I can't get the engine started, I'd best know exactly what is failing to happen.

Before Start

I need to be sure that the inlet and exhaust are free of debris, that the first stage compressor has no visible damage, that the P2T2 probe is clear, the propeller is on the blade angle locks, and that it moves freely. I should check the oil, make sure the speed levers and power levers move freely and are set in the low and just ahead of ground idle positions, respectively. If I'm using a GPU I should make sure it's supplying 24 V and 1000 A, and if I'm using batteries I should check that they have a good charge.

0 - 10% RPM

After the prestart checks are complete, I press and hold the start button. As a result:

  • the #1 start control relay closes
  • the starter relay closes
  • the oil vent valve opens
  • the anti-ice lockout valve closes
  • the starter engages to rotate the engine

And let's see what that all means.

The #1 start control relay "is used to control the starter relay and the oil vent valve during ground starts, and the propeller unfeather pump during air starts." It "also opens the voltage regulator 'B' to starter-generator 'A' lead to prevent field feedback during starts." The first part I get: The #1 start control relay is the electrical string you pull on to get the next two things on the list to happen. If the second part of the description mentioned some kind of particle or anti-matter, I would swear that was from one of the episodes of Star Trek: The Next Generation where Wesley saved the ship again. I can surmise that for some reason the starter-generator has an 'A' lead, that the voltage regulator has a 'B' lead, and that these two are normally connected, but that that connection can lead to undesirable feedback during starts. I can further surmise that the voltage regulator is there to regulate generator output, but seeing as the generator isn't put on line until after it has finished being a starter, that there's no need for it to be connected during start.

The starter relay "energizes the starter generator, during ground starts only." That makes sense, because during air starts the starter is not needed: rotation of the engine from the propeller is sufficient.

The oil vent valve is a clever little kludge to prevent the starter having to work against cold sluggish oil pressure as it rotates the engine. It opens up the oil system to allow it to ingest air during ground starts.

The fuel anti-ice lockout valve closes off the line through which the fuel system cycles cold fuel to a heat exchanger with the oil to prevent ice crystals forming in the fuel. At start the oil isn't warm anyway, so the valve is closed to keep the fuel pressure high.

So that's two things that happen when the start button is pressed, two more that happen because of one of those (or three if we count the A-B lead thing) and one one that happens because of the second wave. And that's all before anything even catches on fire.

10 - 55% RPM

When engine RPM reaches 10% the fire is supposed to start. Specifically:

  • the 10% speed switch closes
  • the #2 start control relay closes
  • the series/parallel relay connects the batteries in series, if selected
  • the SPR valve is energized
  • the fuel solenoid valve opens
  • the 'primaries only' fuel solenoid opens
  • ignition turns on

And I know what most of that means.

The speed switches contain reverse tachyon tribarium warp core interfaces a DC regulating system, a signal conditioning amplifier, timing pulse generators and voltage discriminating circuits (it only allows straight voltages to go through, and the ones with suntans don't get to use the good wires). The speed switches contain STUFF, okay, including three relays. The 10% relay (which the voltage discriminating circuits probably think is an overestimate, or maybe a lifestyle choice) is normally open, the 55% relay is normally closed and the 90% relay is normally open. They receive electrical signals from the "tach gen" which for the purpose of my own amusement I will imagine stands for tachyon generator. Each relay changes its respective state when engine rotation reaches the corresponding speed. The 90% one isn't important to engine starting, but I didn't want to leave it out, as it's probably already getting enough hassle from the voltage discriminating circuits. Best I can tell from the ten pages of starter circuit diagrams, when the 10% speed switch closes, it energizes the #2 start control relay, and the #2 start control relay does the four other things on the list: ignition on, batteries to series, SPR energized and fuel solenoid on.

Hey who thinks I should be allowed chocolate now?

The series-parallel switch sounds like something Scotty would do at the last minute to keep the Enterprise from falling into a black hole.

"It's no use Captain. We haven't got enough juice to get the warp engines online."

"You've got to get them online Scotty, or we're all dead!"

"Well I suppose if I cross connected the dilithium crystals from the other nacelle, it could possibly give enough of a boost to get the warp core online. It's never been done before, laddie."

And then he does it, and it works and the he publishes a paper on the subject, and the manufacturer comes out with a bulletin saying never to do it because it voids the warrantee. It's just like that. In fact it's hard to believe that some desperate pilot didn't invent it while stranded on a reserve somewhere, except that this isn't a bush plane. The manufacturer has set it up so you can flick a switch and the batteries, usually connected in parallel, one to each starter-generator, automatically go into series when the power is needed most. My company, however, says that the power is not needed most at 10% but rather at about 18-28% where there are bad vibrations (seriously, that's the reason), so what I'm supposed to do is start the engine with the series-parallel switch in parallel, but if the engine rpm is at or above 18% and not increasing steadily by 1% per second through 25%, I should flick the switch into series then. I was so impressed by this in groundschool I immediately asked why I wouldn't do it every time. It's because it's very hard on the batteries and if you drain both of them together, you only have one shot, so you have to hit it with your best shot. Also if you do it at night you need to have a flashlight handy, because it will dim the lights and you won;t be able to see the engine instruments.

The SPR valve is another thing they didn't get quite right, according to company procedures. It sounds all cool and modern with the TLA and all, and it stands for Start Pressure Regulator which brings to mind the idea that it might be some sort of computer. Nope. It's the primer. Yeah, the primer. I have to prime this puppy. Primer is available between ten and fifty-five percent rpm, but I should prime it between zero and ten percent, then not prime it between ten and twenty-five, then go back to priming until 55% when the 55% speed switch opens and de-energizes it. The SPR bypasses the fuel control unit and fuel flow transmitter, going straight to the primary fuel nozzles.

The fuel solenoid valve is the thing that lets the fuel into the engine so the igniters have something to ignite. I'm sure that makes them very happy. You can close these valves mechanically with an emergency stop control, but then you can't open them again. Ever. Okay probably not ever. I assume maintenance can fix you up again. The primaries only solenoid allows fuel through only the primary starter nozzles, not the full manifold.

The igniters are not something that I have a lot of information on, but the ignition exciters supply "a nominal high voltage of 18,000' volts to the igniters" so the exciters seem to be serving as fluffers to the igniters. The igniters are some kind of high tech spark plug that lights the fuel. I know they are different than glow plugs, because I flew an airplane once on which some models had glow plugs and some models had igniters and this was apparently different enough that I was supposed to care. (Can you tell I didn't?) I pretended to at the time, and phasers on kill, I swear I will pretend to care about this, too. The igniters light my fire. Can't start a fire without a spark. What is wrong with me? I almost never quote song lyrics. Because I don't know any.

A light comes on when the igniters are working, and the EGT should rise, indicating that something is actually on fire in there, and that the hot exhaust is coming out the right end. When it happens, the pilot can release the start button. If it doesn't happen within ten seconds of reaching 10% rpm, or before reaching 20% rpm, the pilot should shut down the engine. She does this by pressing the stop button, pulling the stop and feather control and then continuing to motor the engine for ten seconds with the starter test switch.

55% RPM

When the 55% switch (which the book calls a 50% switch, but the book is for an older model of engine, so I have to assume that changed) opens, everything that the #1 and #2 start control relays did gets undone, except for the opening of the fuel solenoid:

  • the starter relay closes
  • the starter turns off
  • the anti-ice lockout valve opens
  • the oil vent valve closes
  • the series/parallel relay goes back to parallel, if it was used
  • the ignition turns off
  • SPR becomes unavailable
  • primaries only fuel solenoid closes

Whew, that feels good. It was actually worth it. It took too long, though. I spent a couple of hours on that, between course notes, two manuals and the engine supplement. And stalking around hoping chocolate would spontaneously appear.

Is there some kind of vitamin, found only in chocolate, from which deprivation makes it difficult to study without degenerating into lame Star Trek references, old song lyrics and crude jokes?

I'm also getting antsy, waiting for my training to be scheduled. I have a job offer already, but until I actually go online as a pilot, I don't really have a job. They scheduled the first two while I was there, and I know the second one had a PPC ride today. But it could have been delayed by aircraft or training pilot availability. That happens. Or they decided they hated me and are just going to ignore me. It's not paranoia when they really are out to get you. I e-mailed the chief pilot with a question about where I should send my paperwork, kind of the way I ask ATC for an altimeter setting when I haven't talked to them in a while.

Tuesday, March 15, 2011

Smelly Question

This news story poses a very interesting question. A group of people who had used a toiletry item that had an odour other people found offensive were deboarded from a flight. That's the essence of it, but it's complicated by the fact that the complainers were white and the people they were complaining about were black.

An American judge, Oliver Wendell Holmes, said "The right to swing my fist ends where the other man's nose begins," and this story that shows that there's more than one way to assail a nose. There must be a line somewhere between someone turning up a nose at an unfamiliar odour, and hence at the person attached to it, versus someone truly experiencing physical distress on account of an offensive odour. It's not uncommon for an airline to refuse carriage to someone with extremely poor personal hygiene, and one often sees requests for people to avoid wearing extreme amounts of cologne in public places. But where is that line, and how do you draw it? If I sit next to you in an airplane I can likely smell your shampoo, your hair control products, your deodorant, whether you had garlic for lunch, and whether you're sacred scared. I may find your smell distracting, but would you deserve to be kicked off a plane for it? Smelly is in the nose of the beholder.

I suspect that if the airline offered to accommodate the complaining passengers on a later flight, they may have suddenly found the odour more acceptable.

Monday, March 14, 2011

The Short Bus

When I was working on my commercial licence I met a guy who flew the Screaming Whippet and one of the things I remember him saying about the aircraft was that it had a very complicated electrical system. I was looking forward to meeting this beast, but we were warned in ground school not to pre-read about it in the manual, because there were many options and modifications and that we'd get confused if we did. So it was unveiled on I believe the morning of the second day of class.

It's not so bad. Yeah, it has DC power and three different flavours of AC power, but I can understand the circuitry. There are two 24V lead acid batteries, two 28V starter-generators, and capacity to accept ground power (max 1000A), which can power electrical systems and/or charge the batteries. I've done this enough time that those are pretty standard numbers. The batteries each have their own relay connecting them to the system, then an additional relay connecting the combination, plus the GPU if connected to the battery bus. The battery bus is power distribution central on this airplane. It's located in a junction box behind the left pilot seat, and everything connects to it. Each starter-generator connects to it through a generator relay and a 325A current limiter. The DC battery bus provides power to the left and right essential buses, through 225A current limiters and also to a non-essential bus, through a 150A circuit breaker. The current limiters and circuit breaker are all located in the junction box. Each of those three DC buses described also has a bus tie switch. They are on the circuit breaker panels, under the windows on the left and right sides of the cockpit.

Most of the services are quite predictable, with the left side of the airplane being on the left bus and the right side on the right bus. There are also nine or ten (the tenth is optional) transferable items that can be switched from the left to the right DC bus in the event of a left DC bus failure. They are the turn and bank indicator, the fuel crossflow valve, the valves controlling wing and tail deicing, the windshield heat, the valve controlling left inlet anti-ice, the valve controlling right inlet anti-ice, the flap and gear position indicators, the valves controlling landing gear operation, the solenoid that applies vaccum to open the dump valve and (optionally) the pilot-side DC cockpit instruments. Flaps, nosewheel steering and all exterior lights, including landing lights are on the non-essential bus.

Each essential DC bus has one inverter, and each inverter is connected to 26V AC bus and a 115V AC bus, so four AC buses in total. The L and R 115V buses are connected together through a circuit breaker, as are the two 26V buses, so that with one inverter online, all four buses are powered. Only one inverter can be online at a time. The fuel pressure, oil pressure and some cockpit instruments are on the 26V AC bus. The fuel quantity gauge takes 115V AC. The cockpit edge lighting is powered from the 115V bus, but stepped down to 6V. Other instruments may be on one or the other depending on the airplane, you need to check the CB panels to see.

My brain is full. Remember this two weeks worth of system spam you've been receiving was a three day blitz for me. And I have SOPs and limitations to learn on top of this. I think I'll go jump on the treadmill for an hour. There's too much snow outside to go running, but it's too slushy to go skiing.

Today is Pi Day. You should celebrate by eating pie. You may heat it in an electric, gas or wood-burning, dung-burning or solar powered oven. Or another sort if you have one I didn't think of.

P.S. I got on the scale after jumping off the treadmill. Target weight minus five hundred grams. Booyah! No sugar, no alcohol and get some damned exercise. It works, people. Girl's got legs and she knows how to use 'em. Now to keep it off.

Sunday, March 13, 2011

A Zebra is Its Own Opposite

Kind of funny how "sucks" and "blows" ought to be opposites, but for fellatio, undesirable situations and even airplane systems, they are pretty much the same. The pneumatic system on the Screaming Whippet produces unregulated bleed air ranging up to around 175 p.s.i., regulated 31 p.s.i. bleed air, regulated 18 p.s.i. bleed air and about 4.4 to 5.8 inches Hg suction, all by pulling hot compressed air out of the second stage compressor diffuser.

The way I look at it, the pneumatic system consists of two parts, the part that can be turned on and off with the bleed air switches, and the part that is supplied with bleed air whenever either engine is running. Bleed air tees into these two parts right after leaving each engine. The main bleed air supply to the air cycler and the pressurization system passes though left and right electrically-operated cockpit controllable bleed air valves. Even if those valves are selected open, they are spring-closed when the engine is not running, so open in response to bleed air pressure. The bleed air valves receive DC power from the non-essential bus.

The remainder of the bleed air goes through a smaller line and through check valves to supply everything else with bleed air all the time an engine is running. The two lines combine after the check valves and then divide again, with some supplying a 31 p.s.i regulator to pressurize the hydraulic system, the only system that uses air regulated at that pressure. The rest goes through an 18 p.s.i. regulator. Here there is a connection to the cockpit deice pressure gauge and a 21 p.s.i. pressure relief valve. Some 18 p.s.i. air is drawn off to the pneumatic door seal, some to an air ejector pump, to create suction, and some goes to the distributor valve. All these things are clever, and I will talk about them.

The door seal is clever because when you turn the handle to close the door, not only are you poking bayonets in to align the door, and engaging catches with door frame microswitches that report on whether or not they are properly latched, but you are opening a valve connected to the 18 p.s.i. bleed air. Once the engines are started and bleed air is available, that bleed air seals the door, so you can't turn the latch handle until the engines are shut down. Child safety locks, except that there isn't a button to press on the door frame to disable the feature. One problem is that sometimes moisture in the air can freeze that valve in the open position, so that if the engines are started with the door open (because one crew member is still outside the aircraft to disconnect the GPU) then seal inflates and it becomes impossible to turn the handle to the closed position. Advice we were given for this situation was to either shut down, then start both engines on batteries with everyone inside, or to rapidly operate the deicing boots in an attempt to lower the bleed air pressure enough to wrestle the door shut.

The ejector pump is clever just because it's an ejector pump, I mean how cool is that to create suction from blowing? Ejector (or jet or jet transfer, or injector--same thing) pumps are interesting, and fairly common in aviation, but not necessarily part of everyone's experience. It's a little bit counterintuitive, but if you're willing to accept that the force of something hurtling through a tube creates suction at the junction with other side tubes, then you can be happy like me. The intimate relationship between a thing and its opposite always fascinates me. Refrigerators, prisms, trees growing out of dead logs and ejector pumps rock my world. The air that runs the ejector is dumped overboard, having done its job. The suction line has connections to the pressurization controller, the pneumatic relay and the dump valve, plus there's the expected vacuum regulator, which has a filter, suction indicator and a suction warning switch for the low suction annunciator. I always think that should be high suction. Negative numbers are fun. They are the opposite of positive numbers, but except for a little line, they are the same. Also, I looooove zebras. Black and white both at once and shaped like a horse. There are no zebras in the suction system, but there is a connection to the distribution valve mentioned two paragraphs ago.

The distribution valve is like a four-way intersection with a traffic light (but sadly no zebra crossings). The four streets that meet there are 18 p.s.i. regulated bleed air, suction, wing boots and tail boots. Depending on how the valve is positioned, suction or pressure goes to the wing and/or tail boots. When the deicing is off, suction goes to both. During the auto cycle suction goes to one and pressure to the other, then reverse, then back to both suction. And on the manual deice setting, pressure goes to all boots.

I tried to make this make sense of the earlier story about the inlet anti-ice getting bleed air from two sources, but none of the pneumatic diagrams in my manuals show it. I think it is unregulated bleed air taken before either the bleed air shutoff valve or the 18 psi regulator.

The groundschool went well. Management pilots did a little them-on-one with each of us, answering questions. They intelligently identified the weaknesses in my experience, and I acknowledged them and asserted how I would overcome them. Or at least that's how I remember it. Maybe I just drooled and picked my nose. They scheduled training for the first two, and will call next week when they are through and it's our turn.

Saturday, March 12, 2011

Anti-Ice Without Electrical Heating

Yesterday's post was mostly about electrical heating elements that prevent ice from accreting on various parts of the airframe. Today is about anti-icing measures that do not involve electrical heating, except in as much as the flow of electricity always causes some heating.

The leading edge of the wing and tail are covered in what is essentially a network of bicycle wheel inner tubes stretched out straight, covered in a neoprene sheet and connected to a nozzle. At the pilot's command, an electrically operated regulated 18 p.s.i. bleed air inflates the tubes, called boots and pops off the ice. Whether the pilot commands it or not, at all times that the boots are not being inflated, suction pulls the boots back snugly against the wing. The suction also comes from the 18 p.s.i. regulated bleed air, through the same distributor as the positive pressure. I'll explain how it can both suck and blow later. This system is yet another controlled by a three position switch. The OFF position leaves the solenoids controlling the distributor de-energized, and the wing boots connected to vacuum and sucked against the wing and tail. The AUTO position opens the solenoid allowing 18 p.s.i. regulated bleed air into the wing boots, inflating them for six seconds. Then that pressure is dumped overboard and the wing boots gets sucked back against the wing while the tail boots get inflates for four seconds. After that the system rests for 170 seconds and starts over. The third position is MANUAL and all the boots will remain inflated for as long as the pilot holds the switch in that position. Electrical control of the solenoid can be assigned to either the left or right essential bus.

Inside the engine inlet is a probe called the P2T2 probe (or the R2D2 probe, depending on who is talking). Its job ought to be transmitting pressure and temperature readings for that station to the engine computer, but considering that it is kept ice free with P3 bleed air, it seems that it wouldn't be an accurate indicator of the temperature and pressure there. What am I missing? And does its output have to be translated by a C3PO probe before it can be used? This web page has condescending British people telling someone else who dared ask that anyone at the ATPL level who has to ask questions about a P2T2 probe is lazy and stupider than a toenail. Maybe so, but I know how it's anti-iced. Mostly I know. I'm not sure if it is automatically supplied with bleed air at all times or whether that's part of the inlet anti-ice.

I like the way the anti-ice for the oil cooler works. It simply runs the line taking hot oil from the engine around the lip of the air intake before routing it to the oil cooler. No electricity required.

The fuel anti-icing (i.e. to prevent ice crystals from forming in the fuel thus blocking the filters or lines) also uses heat from the oil, but not quite so simply. As the high-pressure engine fuel pumps draws fuel through the filter towards the fuel control unit, some fuel is routed off to the side, through a heat exchanger, heated with scavenged hot oil and then metered through a temperature-controlled anti-icing valve and sent right back to where it started before the filter. I don't know the exact mechanism; it probably involves a bimetallic controller, but the colder the fuel, the wider the anti-icing valve opens and the more fuel has to take the scenic route through the oil-fuel heater. An additional valve in the system, just before the heater, closes when the engine speed is below about 50 or 55% rpm, to prevent any fuel from being diverted during engine start, the only time such low speeds should occur.

Back to the very low tech, the manufacturer claims that the static ports and fuel vents on the airplane are anti-ice. They have no heating, it's just that the fuel vents are concave and out of the airflow, so there is nothing for ice to build up on, and the static ports are also very flat and at the rear of the aircraft. Just in case they were to ice up, there is an alternate static source located in the unpressurized forward baggage compartment.

There are two more anti-icing systems on the standard aircraft, but they are both irrelevant to this fleet, one because the system it belongs to has been removed, and the other because it was an option not installed.

Also, can someone please tell the person who writes the scripts for my bank's drones to read at me while I try to set up automatic payment on my new credit card that (a) a new credit card is not an occasion for "congratulations," and (b) "I want to inform you some points" is not English.

And in current news, when a huge tragedy strikes, and it's too much to take in all at once, people focus on the corners of it that are most relevant to them. I woke up to e-mail chatter about international flight schedules, plus this video of the tsunami associated with Japan's earthquake hitting an airport. Even people with no international connections have something in Japan they can relate to. I laughed to see the internet hasten to assure us that Maru the Cat and his owner are fine. But what is a mass tragedy if not thousands of individual tragedies, and, thanks to stringent building standards combined with preparation and training, millions of people who can say, "I'm okay, and so is my cat."

Friday, March 11, 2011

Heating Elements: Making Coffee, Shedding Ice

You know you've been reading too many airplane manuals when you can't turn on the coffee maker without thinking, "horizontally-mounted unlabelled three-position rocker switch spring loaded to the centre position, with an adjacent amber indicator light illuminating when the heat cycle has been activated by momentary left pressure on the rocker switch," and then wondering about the circuitry of the heating cycle and of the timer that deactivates it if you walk away and leave it on.

The Screaming Whippet has electrical heating elements, but not for making coffee. Both left and right pitot tubes are electrically heated, from their respective DC power buses, and there is a switchable loadmeter in the cockpit for checking their operation. The pitot heats are operated by a vertically mounted three-position rocker switch, but the upper, pitot heat position is rarely used, in favour of the lower position which heats both the stall indication vane and the pitot tubes. The windshields are also electrically heated, through the largest (60A & 50A) circuit breakers on the airplane, via the left and right essential DC buses. With windshield heat selected to LOW, the panes in front of both the pilot and the copilot are heated together, with single thermostat, such that if the sun is to one side or the other of the airplane and one windshield reaches the 90-100 degree Fahrenheit temperature, it will cycle off despite the other one not being hot yet. With the windshield heat switch set to HIGH the windshields cycle separately, with twice as much power as before going to the captain's side. I'll have to check, but I think the FO may not get any more heat on HIGH.

Let's see, what else is electrically heated? The propellers are. On the leading edge of each blade there is a little grid of wires, kind of like the ones on your car's rear window defogger, except that these are under a rubber cover. There is an inner and outer element, although it looks like just one. And there's a really really long skinny cord so that it can wrap round and round and round the propeller without coming unplugged. No, I'm kidding about that. It's tricky to have an electrical cord on a propeller. There is instead a slip ring assembly with a brush block so that electrical contact can be made without a hardwired connection as the propeller goes round and round about two thousand times a minute. Each propeller heating element draws power through a 25A CB on its same-side 28V essential DC bus. The system operates on a timer, switching on all inner and then all outer elements on either propeller, and it's not crystal clear from the description whether that means a four stage cycle with only one propeller at a time or a two stage cycle with the inner for both props together and then the outer for both props. There's an ammeter that shows the current being supplied to the prop anti-ice; the manual says it should be about 14-18 A per propeller, which suggests to me that they are both on at once. You can switch the ammeter back and forth to show the left propeller or right propeller draw. But then it also says there is a separate timer for each propeller, so I'm not quite sure. When you turn it on, heating starts wherever it left off last, not at any predetermined position.

Propeller heat is on the same switch as nacelle inlet anti-ice, but in the case of a failure of one essential DC bus, only the inlet anti-ice can be switched to the other. Power can not be supplied to the propeller elements on the side with the failure.

I didn't mentioned the inlet anti-ice before the above paragraph, because it doesn't include an electrically heated element, but seeing as it's on the same switch as the propeller heat, I'll put it here. Inlet anti-ice refers to the engine inlet, the part at the front of the engine where air comes in to make the engine work. It is important that this area not become clogged with snow or ice. Instead of using electricity to heat this area, really hot air is blasted into it. This works well and being that the engine inlet is really close to the engine, it has a ready supply of really hot air. It's not exhaust: that's too hot and is at the other end of the engine. (A number of readers will now being going clue! because believe it or not "the exhaust comes out the back of the engine" is not a universal truth with airplanes). This is bleed air that has been heated by compression in the front part of the engine.

I will now quote some facts about the engine intake air from the training manual. Keep in mind this is a training manual, a collection of useful information felt essential for new pilots to learn before flying this airplane. It is not a maintenance and repair manual or a set of blueprints. The first paragraph of the description tells me that bleed air is obtained for this purpose from two different ports, one being "the main anti-icing bleed port" and the other the "cabin pressurization bleed port." It doesn't tell me the relative location of these ports in the engine or how the two sources are different, so I'm not sure why I should care, but in the second paragraph they want to be sure that I know that "the flow from the main anti-icing bleed port runs through an anti-ice valve to a tee: the tee has an orifice of 0.234 inch diameter." Sadly, I will now remember this, and possibly I will also remember that "the line supplying the left-hand side of the distribution duct has a 0.204 inch diameter orifice." Why? Why am I burdened with this information? I understand that the brain does not actually fill up with facts, so that having this one thrust upon me does not decrease the likelihood of my remembering the essential items to complete in case of an engine fire (stop it, close the firewall fuel shutoff, close the hydraulic shutoff, discharge the fire bottle), but still, it's distracting.

Manual-provided information of which I do approve includes more about the switches and annunciator lights. The switches (one for each side) each have three positions: ON, OFF and TEST. In the ON position, the electrically operated valve that allows bleed air to flow through those very specifically sized orifices to do its deicing job is commanded to open, and if the circuitry can verify that the valve did indeed open, the appropriate INTAKE HEAT ON annunciator is illuminated. In the OFF position, the valve should close. Assigning bleed air to this task comes at a cost: a drop in engine torque and a rise in exhaust gas temperature. That is to be expected because the compressed air would otherwise have been used to cool and contain the combustion area and to drive the power turbines. Because of the performance hit we would take if the valves did not motor to the off position when so commanded, electrical power to those valves can be taken from either essential DC bus. There is also a means of verifying that they actually did close: when the switch is depressed to the test position, if the circuitry can verify that the valve is closed, the INTAKE HEAT ON annunciator illuminates. That's kind of backwards, but pretty clever, really. And far more interesting than the diameter of the bleed air orifices. Hey, I just figured out why they included the diameter of the bleed air orifices in the manual. It's to ensure that the test function of the inlet anti-icing valves could be far more interesting than something.

There are more anti-icing measures on the Screaming Whippet, but there are several more anti-icing systems on the airplane, most of which have an electrical component, but I'll put them in a different post, because this one is mainly about heating elements.

Also I've been reading over the details of the job offer. I think this is a real job. Like I get paid extra for working on statutory holidays. Just to keep the Canadian content up, I'll tell you what they are: New Year’s Day, Good Friday, Victoria Day, Canada Day, Labour Day, Thanksgiving Day, Remembrance Day, Christmas Day, and Boxing Day. It seems that for International Ice Cream for Breakfast Day (first Saturday in February) I'll be on my own.

Thursday, March 10, 2011

Juice Holding and Delivery

The airplane has a fairly simple fuel system. At least, I've seen worse. The fuel sits right in the wings, no fancy tanks, no bladders, just fuel everywhere, with the ribs acting as anti-slosh baffles and the five percent dihedral directing the fuel inboard. Yup, it leaks. There are flapper valves on three of the ribs to allow fuel to flow inboard but not outboard. Inboard of the engine nacelle, at the wing root, the inside of the wing is divided along the the chord into three sections: a forward collector tank, a centre hopper tank and an aft collector tank. Two submersible boost pumps are in the fuel in the hopper tank and the tanks are connected to each other and the main body of the wing though flapper valves, allowing fuel into but not out of the hopper tank. The boost pumps (only one per wing can be selected on at a time, so they are used on alternate days) send the fuel towards the engines, but on the way there some of the fuel is diverted down a side line to provide the motive force for a pair of jet pumps (the same as ejector pumps, look it up) to transfer fuel from the collector tanks to the hopper tank and always keep the hopper tank full to its fourteen gallon capacity.

Further downstream in that line is an electrically operated emergency shutoff valve, a filter, with a bypass line in case the filter gets plugged, a fuel heating loop through which an anti-icing valve will automatically meter fuel if need be, a fuel transmitter, engine driven fuel pumps, a fuel control unit, and the engine. There is no crossfeed system, but there's an electrically operated valve you can open that connects the two wing tanks through a pipe, and you can transfer fuel through it by sideslipping, or balance the two sides (they have to be within 500 lbs) by remaining in level flight with it open. Sophisticated, eh?

Fuel indication is through capacitance, with five capacitance probes in each tank. The cockpit fuel gauge reads in pounds and is corrected to read zero when only the thirteen pounds of unusable fuel remains. For reasons I haven't researched, failure of one of the probes causes fuel quantity to overread on the gauge, which requires 115V AC power for its operation. There is also a float switch in the hopper tank which illuminates an annunciator whenever there is less than 13 gallons in the hopper. The annunciator is labelled L/R XFER PUMP, because one reason for there to be less than 14 gallons in a hopper tank is that the corresponding boost pump failed, so the ejectors aren't transferring fuel from the collectors, and there is less than 600-700 lbs of fuel in the tank so that the hopper doesn't stay full anyway. If you turn on the other boost pump in that tank and the light goes out, then you had a bad boost pump. If the light doesn't go out, then it means one of
(a) you have two bad boost pumps and less than 700 lbs of fuel on that side,
(b) the boost pump is working and you have less than 75 lbs of fuel on that side, or
(c) the flapper valve that triggers the XFER PUMP light is stuck.
Option (c) is by far the most likely, and can be verified to near-certainly by knowing how much fuel you put in the airplane and crosschecking with the fuel gauge and the fuel flow totalizer. If no boost pump is working in a tank, the unusable fuel increases to 88 lbs, and the usable fuel will have been exhausted when the gauge reads 75 lbs. Because AC gauges freeze in place when power is removed, there is a test switch on the fuel gauge. When the test switch is depressed, the fuel gauge should indicate zero, if it's working correctly.

Here's some more about the boost pumps. The two pumps on any one side are exactly the same as far as I know, but one is called "main" and the other called "aux," just so you can tell them apart. The switch that controls them is a vertically mounted three position rocker switch, OFF in the middle, MAIN on the top and AUX on the bottom. For each wing the main pump runs on 28.5V DC electric from the corresponding essential DC electrical bus, and the aux pump draws power through the opposite bus. That way, with one essential bus failed, you can still have one operating boost pump in each tank.

There is a gauge showing fuel pressure between the engine-driven low and high pressure boost pumps. It requires 26V AC power and should read 20-30 p.s.i. while the engine is in operation.

And in case you're wondering, yes I am going to just spew airplane systems at you for the next little while. I'm writing multiple ones a day, so they'll last you a couple of weeks. This is what I have to know and do in order to get to the point where you're pushing the throttles forward. Feel free to e-mail me random quizzes on what I profess to know.

Wednesday, March 09, 2011

More Pressure

These puppies have pressurized airframes, and so have an entire system to control the coming in and the going out of the air. Like the other posts in this series, this one will concentrate on what I have to know, with little concession to those who don't know what I'm talking about, but I find it most useful to explain things in quirky ways, so it may be interesting anyway. And feel free to ask questions. You may hit on something I ought to know. The pressurization system includes static ports (holes in the airplane used to sense how rarefied the outside air is), bleed air (compressed air from the engines), an outflow valve (a hole to let the air out), a dump valve (a bigger hole to let all the air out if you need to) a controller (a gauge in the instrument panel with a dial and a knob that you use to tell the airplane how much air to keep inside and how much to dump overboard), a couple of safety valves, a bunch of lines and relays and things, and a couple of gauges that tell you how all that is going for you.

The maximum differential pressure between the inside of the airplane and the outside of the airplane is 7.0 p.s.i., giving a sea level cabin at 16,800' and a 4600' cabin at the service ceiling of 25,000'. The various gauges work kind of like an altimeter or a VSI, comparing reference pressure, cabin pressure and static pressure as appropriate to drive indicator needles. Pneumatic relays associated with the controller create pressure differentials that can drive valves. There is more detail available on this system, but all they need me to know is that I turn knobs to set the controller and that the controller commands things to happen according to my whims, such as allowing or not allowing air out the outflow valve in order to hold the cabin pressure at the set value. The outflow controller will also open if the differential between cabin and external pressure exceeds 7.25 p.s.i. or if the outside air pressure exceeds the inside. When these things aren't happening, a spring holds the outflow valve closed. The training manual describes a number of interesting diaphragms and valves that activate the opening and closing of the outflow valve under different conditions, but they want me to say only that it is opened by vacuum and closed by a spring.

The cabin air pressure dump valve has a similar pressure release function, as the outflow valve, both in the overpressure and underpressure case, plus it can be opened with an electric solenoid valve to dump the cabin pressure, equalizing the cabin with the outside atmosphere. Technically the electric solenoid connects the dump valve to vacuum pressure, causing "the dump valve diaphragm to open the dump valve." But I think I would lose points for getting into that detail, and should say that it is opened electrically, using a solenoid that gets its power from the left essential DC bus, transferable to the right. When pressure is dumped, it is dumped into the nose baggage compartment, which happens to be the same place the alternate static source gets its pressure, so a cabin dump should not be performed while instruments are operating on the alternate static source.

There is also a manual control valve that can be used to bypass the pressure controller and directly adjust the opening of the outflow valve. For the manual valve to have an effect, a switch on the console must be moved from auto to manual. This is the sort of thing I expect from pressurization systems, so you can perhaps get an inkling of the sort of things pilots were yelling at the screen during Snakes on a Plane, which if I recall correctly was the movie in which they solved an overpressurization problem with gunfire through the fuselage.

More interesting than the magic boxes and networks of vacuum hoses is how I use it. First some terminology. The cabin altitude is the altitude I'd be at in an unpressurized airplane for the cabin to be at the pressure it's at. The rate of climb or descent of the cabin is the rate of change of the pressure there. With pressurization, the cabin altitude can be different than the airplane altitude, so that we don't have wear oxygen masks above 13,000'. To set the pressure I dial the controller so that the bottom part displays about a thousand feet higher than the altitude I will be flying at. That way the arrow points to the minimum cabin altitude I can maintain for the flight, without worrying about it banging up and down on small altitude deviations. If the world were flat, I could mostly leave it at that, but airports are at all different elevations and this introduces some issues.

To begin with, the airplane is not pressurized on the ground. It's bad for the airframe to land pressurized, there's no point, you'd have to depressurize to open the door, and why pump up the cabin to an altitude lower than the one the passengers walked in the door at? It wouldn't work anyway, as the dump valve is linked to the squat switch and if it's working properly it stays open on the ground. If you set the cabin altitude to sea level then took off from an airport with a 3000' altitude, as soon as the weight came off the wheels, the dump valve would close and the airplane would try to pressurize the cabin down to sea level. That's just weird, and most people don't like the feeling on their ears when they are descending. The whole point of a pressurized airplane is to avoid that as much as possible. So I set the cabin altitude to the higher of what I will be maintaining in cruise and the departure airport pressure altitude plus a thousand. So coming off a 3000' airport I'd set it to 4000' if I was cruising at 20,000' or below, but if I was going to cruise at 25,000', I'd set the cabin altitude to 5000' or so, because the controller says I can maintain a cabin altitude of 4600' at 25,000'. So I'd take off, the dump valve would close, and the cabin pressure would be 3000'. The controller would not start pressurizing the cabin because it was already at a lower altitude than selected. It would let some air leak out as we climbed to 4000' and then it would stop letting air out and start hoarding it, to keep the cabin altitude at 4000' as the airplane rockets on up to cruise altitude. At top of descent I would set the controller to maintain a cabin altitude about 500' above the landing airport, and a descent rate of 500 feet per minute. If the landing airport were at 1000', that would take five minutes, and meanwhile I could be plummeting through the real descent at 3000 fpm without hurting anyone's ears.

The thing to watch is if the cabin is going to take longer to reach the landing elevation than the actual airplane, because you can "catch the cabin." The problem with that is that the cabin cannot be at a higher altitude than the airplane, because that would mean less pressure inside than outside, and the pressure vessel is only designed to take pressure from the inside. The outflow valve will automatically let in outside pressure if it exceeds the inside pressure, so as soon as you catch the cabin, you feel the descent just as you would in an unpressurized airplane. So to prevent this you can increase the descent rate of the cabin, decrease the descent rate of the real airplane, or level off at an intermediate altitude to allow the cabin to get ahead.

The pressure comes from P3 bleed air, from the second stage diffuser. I'll probably have much more to say about this system once I've actually worked with it.

When I need a break from hard studying work, I start filling out all the company forms. I have to put my height and weight on my security pass application. I'm 1.5 kg above my target weight. I omit the half and put myself down at one above. Or I could wait a week and lose those last 1500g and put down what I should be. I look way better now. You don't notice the little layer when it creeps up on you. A little more butt toning and I'll look the way I want to.