Monday, June 30, 2014
Disowned
One of our aircraft has an optional engine fire extinguishing system installed. The extinguishing system is optional. Engine fires are an option we don't want to exercise. The system is fairly simple, a halon bottle installed in the accessories compartment, a sensor, a couple of lights on the dashboard, and a pair of guarded switches to discharge the bottle. There's very little in the way of documentation, because it's not original to the airplane, but what's called an STC. STC stands not very helpfully for "special type certificate" and what that means is that someone has paid a whole lot of money to have this gizmo approved for this airplane.
I don't actually know how the sensor works. I'm guessing the sensor is based on a bimetallic strip that will bend and close a contact if heated to a temperature hotter than a not-on-fire engine should induce at its location. Or it could be a photocell. I've flown an airplane with a photocell-based fire detection system before. Hmm, wouldn't a photocell result in the fire light going on when maintenance did an uncowled runup in the daytime? I don't think that happens. In the event of an engine fire, I'm supposed to select the appropriate switch in after I have completed the original manufacturer's engine fire checklist.
A fire extinguisher needs to be sent out for hydrostatic testing on a periodic basis, and the ones in the engine are no exception. They have their testing due date stamped on the bottles. The director of maintenance tells me he can't find any information on the STC, can I please research and find the schematics and the maintenance instructions for the unit. I track down the company that bought the company that bought the company that manufactured the STCed (pronounced "ess-tee-seed") system, but they don't have any information on it. They refer me to their European affiliate, which finally tells me conclusively that the product was not profitable for them, so they no longer support it. They have apparently lost or destroyed all information pertaining to the system. Charming.
We will have no choice but to remove it.
Wednesday, June 25, 2014
GFA Challenge
The GFA is a series of aviation weather maps showing what weather is forecast to affect aviation in a given region in the next twelve hours or so. It shows the centres of high and low pressure regions, the fronts, low visibility, clouds and precipitation, and dangerous weather, including icing and turbulence on a separate page. GFA stands for graphical area forecast (yes, the letters are in the wrong order). It replaced the FA (area forecast) about 15 years ago.
The GFA depicts provincial borders and has little circles for locations that have TAFs. (A TAF is forecast that covers the immediate area of an aerodrome). What takes some people a while to realize is that when you mouse over the little circle on the online GFA, text pops up to tell you the name of the place. It would be cooler if you could click on said text to see the latest TAF and METAR (which officially doesn't stand for anything), but I'll take what I can get.
I like to think of it as a little geography quiz. Pull up the GFA page, click on one of the regions, then choose any time. I recommend you pick one of the icing, turbulence and freezing level charts from the right column, because the left column clouds and weather charts can get so busy that you can't see the towns at all. Now try to name all the cities and towns represented by the circles, before you mouse over and see if you're right.
Sometimes one of the little circles doesn't show anything when you mouse over. I think it's usually when it's very close to a weather depiction. Some of the circles represent closed aerodromes where there is no observation or forecast, like Edmonton City Centre. They don't recode the GFA when they close an aerodrome, so it's a history quiz as well as a geography quiz.
The GFA depicts provincial borders and has little circles for locations that have TAFs. (A TAF is forecast that covers the immediate area of an aerodrome). What takes some people a while to realize is that when you mouse over the little circle on the online GFA, text pops up to tell you the name of the place. It would be cooler if you could click on said text to see the latest TAF and METAR (which officially doesn't stand for anything), but I'll take what I can get.
I like to think of it as a little geography quiz. Pull up the GFA page, click on one of the regions, then choose any time. I recommend you pick one of the icing, turbulence and freezing level charts from the right column, because the left column clouds and weather charts can get so busy that you can't see the towns at all. Now try to name all the cities and towns represented by the circles, before you mouse over and see if you're right.
Sometimes one of the little circles doesn't show anything when you mouse over. I think it's usually when it's very close to a weather depiction. Some of the circles represent closed aerodromes where there is no observation or forecast, like Edmonton City Centre. They don't recode the GFA when they close an aerodrome, so it's a history quiz as well as a geography quiz.
Friday, June 20, 2014
Taxiiway Closures
I'm arriving at an airport with no control tower, and no flight services on the field, but it's a mandatory frequency, and this time of day the radio is answered by a flight services specialist at another airport. It's not an uncommon situation in Canada. It's funny sometimes listening when a pilot doesn't realize that the control tower at the airport he has just landed at is unoccupied, and asks questions like, "Is this a good place to park?"
The descent is over rugged forest with little lakes in it. I point out a boat on the lake to a new, non-pilot crew member, part of my running commentary on what I'm doing, so they get to know what is normal. I called the flight services specialist about 30 miles out and then again entering the zone. The specialist tells me that three out of the four taxiways are closed, rattling off the identifying letters. This is the wrong part of the flight for me to be fumbling for a publication to determine how this should affect my runway choice or route to the fuel pumps. Taxiway letters don't correspond in an obvious way to the runway layout. How could they, with so many ways to lay out runways? I do know of an airport with taxiways S to the south and E to the east, but even that makes no sense without the diagram out the CFS, Did I miss this mess in the NOTAMs? I often check NOTAMs the night before and not morning of, and perhaps I missed this airport.
I can see a vehicle parked across one of the taxiways. Another pilot on frequency says somethign about "these baldies." Bald eagles, he means. They're the most common kind of eagle around here. I was about to describe one, but guess everyone in the world knows what they look like, because they're an American symbol. There's one near my altitude, but fortunately not right in my path. I flare, and no eagles decide to challenge me.
I tax off the runway and negotiate my way to the apron. There is construction going on, and large trucks trundling to and fro. We get to the fuel pumps without incident and refuel. At the end of the day I recheck NOTAMs. There is nothing for this airport about taxiway closures, just three unlighted towers and some non-standard runway markings. Ubiquitous enough NOTAMs that I hadn't written them down.
I call to talk to a flight briefer to see if I've missed a NOTAM somewhere. Nope, they don't have anything either. I tell them about the construction.
This sort of thing undermines my confidence in the system. I depend on this system to tell me if there is fuel and a place to put my wheels when I land. I check NOTAMs again in the morning. Now there are two unlighted towers plus non-standard runway markings. Overnight someone either put up some lights or took down a tower, I guess. But the construction still doesn't exist.
The descent is over rugged forest with little lakes in it. I point out a boat on the lake to a new, non-pilot crew member, part of my running commentary on what I'm doing, so they get to know what is normal. I called the flight services specialist about 30 miles out and then again entering the zone. The specialist tells me that three out of the four taxiways are closed, rattling off the identifying letters. This is the wrong part of the flight for me to be fumbling for a publication to determine how this should affect my runway choice or route to the fuel pumps. Taxiway letters don't correspond in an obvious way to the runway layout. How could they, with so many ways to lay out runways? I do know of an airport with taxiways S to the south and E to the east, but even that makes no sense without the diagram out the CFS, Did I miss this mess in the NOTAMs? I often check NOTAMs the night before and not morning of, and perhaps I missed this airport.
I can see a vehicle parked across one of the taxiways. Another pilot on frequency says somethign about "these baldies." Bald eagles, he means. They're the most common kind of eagle around here. I was about to describe one, but guess everyone in the world knows what they look like, because they're an American symbol. There's one near my altitude, but fortunately not right in my path. I flare, and no eagles decide to challenge me.
I tax off the runway and negotiate my way to the apron. There is construction going on, and large trucks trundling to and fro. We get to the fuel pumps without incident and refuel. At the end of the day I recheck NOTAMs. There is nothing for this airport about taxiway closures, just three unlighted towers and some non-standard runway markings. Ubiquitous enough NOTAMs that I hadn't written them down.
I call to talk to a flight briefer to see if I've missed a NOTAM somewhere. Nope, they don't have anything either. I tell them about the construction.
This sort of thing undermines my confidence in the system. I depend on this system to tell me if there is fuel and a place to put my wheels when I land. I check NOTAMs again in the morning. Now there are two unlighted towers plus non-standard runway markings. Overnight someone either put up some lights or took down a tower, I guess. But the construction still doesn't exist.
Sunday, June 15, 2014
Late Spring
An airplane in Canada is legally required to be equipped with a working oil pressure gauge for each engine. When you start a piston engine, your eyes go to the oil pressure gauge. You're waiting for the pressure to come up. Given that it's the first thing you do on starting an engine, it's one of the first things I learned as a student. (Right after, "in order to start an engine, you have to turn the key to the start position and hold it there until the engine has actually started," which was explained to me immediately after I did it the wrong way. Yeah, I was pretty dense). If the pressure doesn't come up, you're supposed to shut down the engine and not do anything else.
I'm not sure I've ever followed that instruction. I am starting an engine that I have just verified has oil in the crankcase and does not have a huge puddle of oil on the ground underneath. And I know how hot or cold that oil is, from 'so hot that I had to use a rag to handle the dipstick, and couldn't really see a level anyway', to 'I just spent twenty minutes deicing and I can't feel my toes or fingertips'. If it's the latter, yeah, I know that oil isn't going to come dancing through the tiny line to the pressure gauge in any big hurry. I will give the oil a while to warm up, and thus the oil pressure more time to increase.
In retrospect, I wonder if disciplining student eyes to go straight to the oil pressure gauge was a way of training us to be vigilant for a hot start when we move on to turbine engines.
High oil pressure can be a sign of a blockage, or you're running summer weight oil too far north, so instead of distributed cooling slipperiness, the oil is a viscous glob having trouble getting forced through some part of the system. Yeah, oil that is too thick can cause high or low oil pressure indication, because unless you're short on oil, both high and low oil pressure indications are caused by poor oil circulation. The pressure is high one place and low another place. Or it's the gauge. Low or high oil pressure, it's usually the gauge.
Even when its probably not the gauge, so long as there isn't oil splattered all over the airplane, and the engine didn't quit, the pilot rolls up to maintenance and says, "I have a low oil pressure indication, but it's probably just the gauge." You never want to give maintenance the idea that you are terrified of the airplane they gave you. I'm not sure why we do this. Perhaps I should try the opposite strategy sometimes and insist that ... oh wait I did that last week with a stuck propeller cable that turned out to be ... maybe I'll admit that one another time. While instantly diagnosable by someone leaning into the cockpit from the right-side door, it really wasn't visible to someone strapped into the left seat. Anyway, under-reporting of the severity of our concerns seems to be a pilot thing. Maybe because maintenance likes to show us to be wrong, so if we show little concern, they will work hard to find some way it could have killed us. Which is what we want them to do.
So my story is, I report unequal oil pressure on several consecutive flights in this airplane. It's in the green on both engines, I concede, but used to be equal, I think. I didn't remember there being a split, and I would. A pilot scans the engine instruments far more times than she knows, because we only notice we're doing it when something is wrong, and the two needles for the same thing on the two engines not being in the same position on their adjacent dials comes up as wrong, even when they are both in the green. The oil pressure indication on the right engine is inching up slowly. If it were a single engine airplane I probably would not notice. That's something I say a lot, but I keep reporting these things, because sometimes it matters. It's remarkable what a tiny thing can be a symptom of.
Eventually the needle reaches the yellow and they take it apart and find out what was wrong with it. An oil pressure gauge works the only way one logically could but I was still kind of flabbergasted when I realized that a little pressure line comes off the oil system, ducting a bit of the engine-pressure oil right to the instrument in my dashboard. Its internals consist partly of a ball bearing and a spring, and the pressure of the oil on the ball bearing compresses the spring, driving the needle. The spring was worn out.
I'm not sure I've ever followed that instruction. I am starting an engine that I have just verified has oil in the crankcase and does not have a huge puddle of oil on the ground underneath. And I know how hot or cold that oil is, from 'so hot that I had to use a rag to handle the dipstick, and couldn't really see a level anyway', to 'I just spent twenty minutes deicing and I can't feel my toes or fingertips'. If it's the latter, yeah, I know that oil isn't going to come dancing through the tiny line to the pressure gauge in any big hurry. I will give the oil a while to warm up, and thus the oil pressure more time to increase.
In retrospect, I wonder if disciplining student eyes to go straight to the oil pressure gauge was a way of training us to be vigilant for a hot start when we move on to turbine engines.
High oil pressure can be a sign of a blockage, or you're running summer weight oil too far north, so instead of distributed cooling slipperiness, the oil is a viscous glob having trouble getting forced through some part of the system. Yeah, oil that is too thick can cause high or low oil pressure indication, because unless you're short on oil, both high and low oil pressure indications are caused by poor oil circulation. The pressure is high one place and low another place. Or it's the gauge. Low or high oil pressure, it's usually the gauge.
Even when its probably not the gauge, so long as there isn't oil splattered all over the airplane, and the engine didn't quit, the pilot rolls up to maintenance and says, "I have a low oil pressure indication, but it's probably just the gauge." You never want to give maintenance the idea that you are terrified of the airplane they gave you. I'm not sure why we do this. Perhaps I should try the opposite strategy sometimes and insist that ... oh wait I did that last week with a stuck propeller cable that turned out to be ... maybe I'll admit that one another time. While instantly diagnosable by someone leaning into the cockpit from the right-side door, it really wasn't visible to someone strapped into the left seat. Anyway, under-reporting of the severity of our concerns seems to be a pilot thing. Maybe because maintenance likes to show us to be wrong, so if we show little concern, they will work hard to find some way it could have killed us. Which is what we want them to do.
So my story is, I report unequal oil pressure on several consecutive flights in this airplane. It's in the green on both engines, I concede, but used to be equal, I think. I didn't remember there being a split, and I would. A pilot scans the engine instruments far more times than she knows, because we only notice we're doing it when something is wrong, and the two needles for the same thing on the two engines not being in the same position on their adjacent dials comes up as wrong, even when they are both in the green. The oil pressure indication on the right engine is inching up slowly. If it were a single engine airplane I probably would not notice. That's something I say a lot, but I keep reporting these things, because sometimes it matters. It's remarkable what a tiny thing can be a symptom of.
Eventually the needle reaches the yellow and they take it apart and find out what was wrong with it. An oil pressure gauge works the only way one logically could but I was still kind of flabbergasted when I realized that a little pressure line comes off the oil system, ducting a bit of the engine-pressure oil right to the instrument in my dashboard. Its internals consist partly of a ball bearing and a spring, and the pressure of the oil on the ball bearing compresses the spring, driving the needle. The spring was worn out.
Tuesday, June 10, 2014
Ups and Downs
Pilot Proficiency Check. Flight test time. The examiner is a check pilot from another company. The ride is scheduled for Friday. I make sure all the right exams have been written and recurrent training signed off. The examiner calls on Thursday. "Let's do it today. The weather will be better than tomorrow." Why stress for another day when I don't have to?
The examiner doesn't enjoy sitting in an airplane watching people stress out. He just wants this over. After one turn in the hold my inbound leg is too short and I never really intercepted the inbound track completely. That's not abnormal for the first time around on a parallel entry. He asks me how I will correct for the wind, and when I tell him how long I will fly outbound for and on what heading, to try to make the next inbound a neat one minute line along the appropriate radial, he is satisfied and calls for the NDB approach.
I tell him I will fly two minutes outbound from the beacon before turning inbound, but he gets bored watching the scenery go by and tells me to turn in early. This puts me high on the approach. I know that is the main hazard of this step down approach, not being able to make the step down altitudes. It's why I chose the two minute outbound. Now I'm fighting to get down and not overspeed my flaps and gear. I don't make the MDA by the missed approach point. I'm too high to land. It wasn't a trick on his part, he was just impatient. He sees what he did, and says he won't fail me. Still I should have refused the early turn. I know my airplane. I'll take the low score there.
When I get the ride report back I grimace again that it's only good for a year. An instrument rating only has to be renewed every two years, and not too long ago PPCs were good for the same length of time, but they've now shortened it to one year. The first time that happened I called the examiner up to tell him he's made an error on the paperwork. But there's a good thing, too. He didn't even give me a 2, the lowest passing grade on that approach. It's a three, the "minor errors" rating. I don't know if he forgot, or felt badly for asking me to turn early. At any rate I'm licensed to commit aviation in this aircraft for another year.
The examiner doesn't enjoy sitting in an airplane watching people stress out. He just wants this over. After one turn in the hold my inbound leg is too short and I never really intercepted the inbound track completely. That's not abnormal for the first time around on a parallel entry. He asks me how I will correct for the wind, and when I tell him how long I will fly outbound for and on what heading, to try to make the next inbound a neat one minute line along the appropriate radial, he is satisfied and calls for the NDB approach.
I tell him I will fly two minutes outbound from the beacon before turning inbound, but he gets bored watching the scenery go by and tells me to turn in early. This puts me high on the approach. I know that is the main hazard of this step down approach, not being able to make the step down altitudes. It's why I chose the two minute outbound. Now I'm fighting to get down and not overspeed my flaps and gear. I don't make the MDA by the missed approach point. I'm too high to land. It wasn't a trick on his part, he was just impatient. He sees what he did, and says he won't fail me. Still I should have refused the early turn. I know my airplane. I'll take the low score there.
When I get the ride report back I grimace again that it's only good for a year. An instrument rating only has to be renewed every two years, and not too long ago PPCs were good for the same length of time, but they've now shortened it to one year. The first time that happened I called the examiner up to tell him he's made an error on the paperwork. But there's a good thing, too. He didn't even give me a 2, the lowest passing grade on that approach. It's a three, the "minor errors" rating. I don't know if he forgot, or felt badly for asking me to turn early. At any rate I'm licensed to commit aviation in this aircraft for another year.
Thursday, June 05, 2014
On the Radio Lately
Today I give you a collection of things pilots and controllers have said that made me smile enough to scrawl them on my OFP.
--
Controller: Aircraft calling, standby. Aircraft .. everybody just standby.
--
Pilot: Centre, Aircraft Z, Any chance of direct the beacon?
ATC: No. [no call sign, just 'no']
--
Pilot: Centre, Aircraft Y, 60 nm W of fix, 16,000.
Centre: That's lovely. You should tell Approach on <freq>.
---
Pilot: <Gives aircraft position report parked at an FBO>
Controller: This is the departure frequency. We'll talk to you later.
--
A controller makes several calls without a reply, to an American Mustang that has been having fun shooting approaches into fogbound airports. Good practice. I've heard that guy up here before. The pilot finally comes back says he had a radio problem. A few minutes later the same controller loses contact with another US airplane. "No one is listening to me today," he laments on frequency.
--
Controller. "Where is that? My map is crappy."
--
Controller: Aircraft calling, standby. Aircraft .. everybody just standby.
--
Pilot: Centre, Aircraft Z, Any chance of direct the beacon?
ATC: No. [no call sign, just 'no']
--
Pilot: Centre, Aircraft Y, 60 nm W of fix, 16,000.
Centre: That's lovely. You should tell Approach on <freq>.
---
Pilot: <Gives aircraft position report parked at an FBO>
Controller: This is the departure frequency. We'll talk to you later.
--
A controller makes several calls without a reply, to an American Mustang that has been having fun shooting approaches into fogbound airports. Good practice. I've heard that guy up here before. The pilot finally comes back says he had a radio problem. A few minutes later the same controller loses contact with another US airplane. "No one is listening to me today," he laments on frequency.
--
Controller. "Where is that? My map is crappy."
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