The Second Best Place To Set a Bomb

An airplane I flew today had an oddly located fire extinguisher. While looking up the rules in CARS 525 on where the fire extinguisher has to be with respect to the pilot's duty station, I found some rules on airplane interior design that weren't there when I learned to fly.

(c) An aeroplane with a maximum certificated passenger seating capacity of more than 60 persons or a maximum certificated take-off gross weight of over 100,000 pounds (45,359 Kilograms) must comply with the following:
(amended 2010/06/16; no previous version)

    (1) Least risk bomb location. An aeroplane must be designed with a designated location where a bomb or other explosive device could be placed to best protect flight-critical structures and systems from damage in the case of detonation.

According to this FAA document the Least Risk Bomb Location (LRBL) has been a thing since approximately 1972. The crew should be aware of the LRBL, but we can be forgiven for not knowing, as the guidance document includes a prohibition on marking it with cute international graphics or bilingual block lettering saying something like "place unattended bombs here." For more information on determining the best location of an LRBL, you may consult a document entitled “DHS Recommended Least Risk Bomb Location Procedures for Airlines,” Sensitive Security Information (Limited Distribution). The FAA will need your letterhead and an e-mail address. I hope they do more than glance at the letterhead and go, "ooh, it's embossed, and someone used expensive design software on this, they must be a legit airline. Quick, e-mail them the secret LRBLs." Probably they have more secure procedures than that, but the whole letterhead thing is so quaint that I had to make fun of it.

If you don't have a need to know, or a fancy letterhead, you can still find out about LRBLs. The public document is interesting enough, with little diagrams and recommendations on how the LRBL should work. If you click through to look a the document, don't forget to scroll down to the name of the person responsible for it, and imagine how much fun he has at airports when he's "randomly" selected for special screening based on his name, and then they discover his carry one is full of Sensitive Security Information about where to put bombs on airplanes. Whatever city he lives in, that's where the meetings are.

The airplane I fly does not have a passenger seating capacity of more than 60 persons. Were we to discover a bomb on board, I would direct it to be thrown out the emergency exit. Such a measure would be an extreme emergency procedure for me, but its physically impossible to open an exit on a pressurized aircraft in flight, because the exits are plugs held in place by the pressure. The only way to open one would be to blow it up. The implication of the document is that that's kind of what some LRBLs do. It also points out that decompression is less harmful if it's not done explosively, so I imagine the "oh no there's a bomb on board" procedure involves an emergency descent and controlled depressurization. The descent would be so that by the time the airplane was depressurized and the oxygen in the generators was exhausted, the ambient oxygen would be sufficient to sustain the surviving passengers.

    (2) Survivability of systems:
        (i) Except where impracticable, redundant aeroplane systems necessary for continued safe flight and landing must be physically separated, at a minimum, by an amount equal to a sphere of diameter
        D = 2 v (H0 / P )
        (where H0 is defined under 525.365(e)(2) and D need not exceed 5.05 feet (1.54 metres)). The sphere is applied everywhere within the fuselage limited by the forward bulkhead and the aft bulkhead of the passenger cabin and cargo compartment beyond which, only one-half the sphere is applied.
        (ii) Where compliance with subparagraph (c)(2)(i) of this section is impracticable, other design precautions must be taken to maximize the survivability of those systems.

I think that is meant to imply that if you want to take out redundant systems, you'll need more than one bomb. Plus I'll throw you overboard with your bomb.

    (3) Interior design to facilitate searches. Design features must be incorporated that will deter concealment or promote discovery of weapons, explosives or other objects from a simple inspection in the following areas of the aeroplane cabin:
        (i) Areas above the overhead bins must be designed to prevent objects from being hidden from view in a simple search from the aisle. Designs that prevent concealment of objects with volumes 20 cubic inches and greater satisfy this requirement.
        (ii) Toilets must be designed to prevent the passage of solid objects greater than 2.0 inches in diameter.
        (iii) Life preservers or their storage locations must be designed so that tampering is evident.

What and ruin the plot of so many bad airplane movies? At least there's no rule about disabling the secret passage out of every airplane washroom into the giant avionics bay. I think the life jacket one is interesting. I've never noticed the lifejacket pouches to appear particularly tamper-resistant.

(d) Each chemical oxygen generator or its installation must be designed to be secure from deliberate manipulation by one of the following means:
(effective 2015/03/20)

    (1) by providing effective resistance to tampering,
    (2) by providing an effective combination of resistance to tampering and active tamper-evident features,
    (3) by installation in a location or manner whereby any attempt to access the generator would be immediately obvious, or
    (4) by a combination of approaches specified in (d)(1), (d)(2) and(d)(3) of this section that the Minister finds provides a secure installation.

(e) Exceptions. Aeroplanes used solely to transport cargo only need to meet the requirements of (b)(1), (b)(3) and (c)(2) of this section.
(effective 2015/03/20)

I haven't yet seen a bad airplane movie in which the bad guys repurpose the oxygen generators as poison gas grenades, but maybe it was so awesome I forgot.

Oxygen Exchange

I work in an unpressurized aircraft at altitudes where the atmospheric pressure is low enough that oxygen is required. Between 10,000' and F180 (about 18,000') I wear a nasal cannula: an arrangement of tubes, including two blowing oxygen up my up my nostrils. Above FL180 I wear a mask that covers my nose and mouth. I could skip the cannula and wear the mask any time I was above 10,000' but I can't eat or drink while wearing it, so it gets old fast. Plus the design of the cannula is such that it recycles exhaled oxygen, meaning that the oxygen supply lasts a lot longer on cannulas. Thus we only use the masks if we're working above 18,000'.

Putting the mask on involves taking off my headset, putting the mask over my face, pulling the head strap into place, putting the headset back on, and fastening another mask strap behind my neck. Finally I have to swap the microphone plug for the headset boom mike with the microphone plug for the in-mask mic. I can do all this before take-off, which I will if I'm in busy airspace. I started up next to a military jet once and noticed its pilot put on his oxygen mask before start up. If I am in uncontrolled airspace, I typically put my mask on just before I climb through 10,000'. If I'm expected to be monitoring a frequency, I wait until a needy or slow-talking pilot starts to make a call irrelevant to me, and then I can get the headset off, mask on, and headset back on before the call is over, ensuring I don't miss any calls. It takes less than thirty seconds. On descent, I can use the same technique, or just leave it on until I park, likely confusing the FBO marshallers.

Sometimes the day starts out with an hour of work at at 20,000' and then progresses to three more at 15,000'. Obviously I need the mask for the high level work, but would prefer to be able to eat and drink for the rest of the flight. In this case the swap involves all of the above, plus disconnecting the mask from the oxygen receptacle, connecting the cannula, and putting the cannula in my nostrils. It looks just like the cannulas the patients in House wear, but rather than looping around my ears and hanging down in front, it just goes around my head, held up by my headset earcups, and secured in place with a baseball cap. The point of this post is that I think about perfecting the swap between oxygen supplies at altitude. Should I breathe normally, or hold my breath during the swap?

The way breathing works is that the partial pressure in the air I inhale is greater than that in the lung capillaries it is in contact with. The imbalance causes oxygen to diffuse into the capillary, until the partial pressures are equal, the way any gas does across any membrane. So if the partial pressure in the ambient air is less than that of my lung capillaries, the act of breathing will actually decrease the oxygen level in my blood, and it would be better to hold my breath while I switch between mask and cannula.

The partial pressure of oxygen in ambient air at sea level is 21% of 29.92 inches of mercury, which is 6.28 inches of mercury. I'm going to convert that 160 mm Hg, not because I'm obsessed with metric, but because Wikipedia gives me biological numbers in millimetres of mercury so I have to convert one of them in order to do the math. At 18,000' the partial pressure of oxygen in the ambient air is half that at sea level, so 80 mm Hg. The partial pressure of oxygen in lung capillaries at sea level is 20-40 mm Hg, and as the mask maintains my blood oxygen at the same saturation as at sea level, then that's the partial pressure of oxygen while I'm wearing an oxygen mask. Eighty is clearly greater than forty, so even at 18,000' breathing is better than holding my breath to maximize blood oxygen during the mask swap.

So at what altitude should I hold my breath? At 32,800' the partial pressure of oxygen in the atmosphere is 25% of the sea level pressure, which is 40 mm Hg, the top of the range for lung capillary pressure. I would say, "so up to 32,000 it's better to breathe than hold one's breath when swapping oxygen sources" but above 32,000' the time of useful consciousness without oxygen is around a minute, even with no physical activity, so one shouldn't be messing around with one's oxygen source at such altitudes. But my conclusion is that above that, hold your breath for those few seconds of scrabbling before you either get your oxygen on or forget how and pass out.

I only took biology to about grade eight, so most of what I know about the human cardiovascular system comes from lifeguard class. I welcome any corrections to this analysis, even if you're stopping by years after I wrote it.

For Altitude

I'm in an area of complex controlled airspace. One agency, a big city tower, controls the airspace from the surface up to 4000'. Above that, the terminal controller is responsible for airspace up to to 12,500', and Centre controls everything above 12,500'. I've been working in high level airspace, but have now descended and am talking to terminal. They know my intentions: to land at an airport just past the big city. They've told me to maintain 6500' VFR. I do this, following the route they specify, following landmarks, then an assigned heading and then direct a nav aid. They have traffic below me, but I must be past it now, because they tell me I'm cleared to 4500', contact tower for lower.

I'm expecting this, so I have the tower frequency already tuned on standby. After I acknowledge the instruction, I push the button to switch to tower frequency. I don't call immediately, because I need to listen for a moment to make sure I'm not interrupting a conversation. I start descent and then call tower, giving them my call sign and that I'm passing "six thousand two hundred for four thousand five hundred." The first number is the altitude they can crosscheck with my transponder readout, and the second number is the altitude I was cleared to.

The tower controller says that he is not responsible for that airspace, and that I should call terminal. "Terminal sent me to you," I say. It's not uncommon for there to be miscommunication between tower and terminal. The tower controller tells me to go back to terminal then, because 4500' is not in his airspace. And now I know the problem: although my destination should be encoded on my radar blip, either the tower controller hasn't looked at it or it's been miscoded. I tell him the airport I want to land at and he clears me down through his airspace for it, grumping that I should have asked for that in the first place.

I wonder out loud to my coworker about who put a frog in the tower controller's cocoa, and continue my descent. But I see the ambiguity there. Pilots say, "Niner thousand for six thousand five hundred," both to request a descent to six thousand five hundred and to indicate a descent in progress, with the intention of stopping there. The latter could be a clearance limit in uncontrolled airspace, or just a pilot stating her intentions, if the descent will take her out of controlled airspace. I could have said "six thousand two hundred requesting descent for ." I went out again and came back the same way later that day, with similar clearances, and I think I used the latter wording without incident.

UK-trained pilots will jump in now with radiotelephony rules, because their language and training is more precise. I agree ours should be, and am somewhat surprised that in thousands of hours of flying this is the first time this particular ambiguity has bitten me. I suppose there have been numerous times when the second controller has taken my statement of an existing clearance to be a request, and recleared me to that altitude, but they didn't stand out enough for me to realize the ambiguity.

Controllers are damned smart. I think most of the time they just figure it out.

By the Numbers

I'm descending out of the flight levels on a sunny day. The airspace I'm descending through is green on the IFR chart, meaning that it's uncontrolled even above FL180, so I have been working with only a company flight itinerary, no IFR flight plan, just me and the company flight follower.The sky is littered with little puffy clouds, based around ten thousand feet, but the scenery is clearly visible below. I can see a ridge of trees, a long lake with a river at each end, a little settlement, and a runway parallel to the lake. It's just as the CFS and sectional say it should be.

I advise traffic of my presence and intentions on 126.7 and on the aerodrome frequency, but there doesn't seem to be anyone around. Through ten thousand feet, oxygen selected off. My oxygen mask is on underneath my headset so I can't take it off without taking off my headset, and that will also knock my glasses off, so for now I'll just plummet, breathing now the ambient air that sucks into the mask. Altitude falling, temperature rising, runway coming into view. I glance again at the diagram I've scribbled on my kneeboard to remember the runway numbers and the location of the exit taxiway. I advise traffic I'll be downwind for my chosen runway, and I join the circuit, a thousand feet above runway elevation, parallelling the runway just far enough away to see it by my wingtip. Flap speed, approach flap set. Abeam the touchdown point, gear speed, gear selected down. Three green lights, turn base, continue descent and increase flap to one half. Turn final, roll out. I can see the runway straight ahead, a sawmill underneath and the lake beside me. I call final to the traffic that isn't there to hear me, and add the last increment of flaps, letting the speed bleed back to blueline and then below as I ease over the threshold and ...

What? The runway number is not the one in the publication. It's not the opposite end either, nor is it freshly painted. I haven't been here in many years, so don't remember the airport layout, but there's no way I'm not at the right airport. I let the main wheels clump onto the runway and then lower the nose for the rollout. I have to backtrack to exit, so I have opportunity to see again. No, this is definitely not the runway number that appears in the book.

After shutdown I look at the CFS again. Yup, I have the right airport. I recheck the date on the CFS, even though I know when all my pubs expire and this set is fine. Yup, the CFS is current. I pull up NOTAMs on my phone, looking for the one I must have missed. Nothing for this airport at all.

I call Flight Services and ask if the NOTAM has been accidentally deleted or misfiled or something. They tell me I must have out of date publications. I assure them I wouldn't call them if I hadn't checked that, and that despite being a pilot I do know all my numbers, and the ones painted on the runway are not the ones in the book. The most disturbing thing about the whole conversation is how little the flight services specialist seems to care. This is a big deal. This is a major identifying characteristic of the airport. A friend said that if he came down an ILS and the numbers at the bottom didn't match the numbers on the chart, he would put in the power and go around. If the official publication is wrong about the numbers, how do I know I can trust what it says about runway length, elevation or anything else? The numbers aren't even newly painted. Am I the first pilot to care enough to report this, or has it been ignored so long?

Yes, every once in a while they have to change runway numbers. This happens either because the shift of magnetic north is sufficient that the runway is no longer aligned within a fair tolerance with the heading its number designates, or because the airport is building more runways and what was once plain old runway 14 is now runway 14L. But this sort of thing should be accompanied by NOTAMs, probably beginning with runway 14/32 closed for maintenance followed by amend publication: runway number 15-33 vice 14-32 and finishing off with a new cycle of publications that all show the correct new runway number. It should be a pretty standard process.

I depart the next day, this time calling the runway by the number painted on the pavement, and climb through ten thousand feet before I can get a hold of centre. I really feel like I'm in the land beyond civilization. I leave it behind and end the day at a little airport in another province. And it also has the wrong runway numbers! Is someone trying to drive me insane? I report this one too, and either they care more about such things in this province or the ranting lady tone in my voice warns the specialist to humour me, because he seems to appreciate more than the previous one that this is something that Should Not Happen. I'd never seen that in my whole career, and then I get two on consecutive days.

Choose Your Own Misadventure

You are the commander of a Boeing 737 passing through 10,000' and setting up for a visual approach. You realize that you have misjudged the wind and your descent profile. You are likely to be too high and fast. You:
a) extend speed brakes
b) fly further out than usual before turning final
c) recheck your calulations
d) nose down and go faster, hoping it will work out

You are still high and fast. You call for flap 15 but the co-pilot does not respond to your request. You:
a) ask him why he did not do as you asked
b) yell at him
c) extend them yourself
d) continue the approach without flaps

You are on final approach and the flaps are set to five degrees extension. The manual calls for at least thirty degrees of flaps for landing, but the manual also calls for a much lower airspeed before extending that much flap. You:
a) try to extend the flaps anyway
b) leave them up and land anyway
c) conduct a missed approach

You believe the flaps are malfunctioning, as you have selected them down but the airplane is not slowing as it usually does. You:
a) continue the approach at high speed
b) check all your power settings and other parameters
c) conduct a missed approach, extend the flaps at altitude and have a crew member go aft to the passenger cabin to confirm the position visually

You encounter windshear on approach to a runway. You:
a) conduct a missed approach in accordance to your company procedures
b) land with minimal flaps at above normal speed
c) continue at whatever speed and configuration you can attain, just to get the airplane on the ground.

You are at the position on the approach where your company manual calls for you to be stabilized. You are so high and so fast that the airplane automated systems think you are crashing. You:
a) attempt to land
b) conduct a missed approach

You are almost a hundred feet above the runway threshhold, well above landing speed and not in landing configuration. The copilot is telling you to conduct a missed approach, and does not confirm landing checks complete. You:
a) attempt to land
b) conduct a missed approach

You touch down over a third of the way down the runway, at well over maximum tire speed. The airplane bounces twice, pulling almost three Gs, and the nose gear collapses while the copilot yells at you to go around. One of the engines comes off its pylon. You:
a) kill 22 people and injure almost everyone else.

Sadly, there is only one choice in the end, and that is the adventure a real life commander chose.

Indonesian pilot Marwoto Komar has been sentenced to two years in jail after being found guilty of criminal negligence for attempting to land a Boeing 737 in the wrong configurations and at almost twice the normal speed. The jet overran the end of the runway into a rice field. Twenty-two people were killed and fifty were seriously injured in the crash and ensuing fire. The Daily Telegraph story here includes a dramatic photo of the post crash fire.

According to the investigation report, the aircraft was already fast through 10,000' on the approach, as they exceeded the crew accepted a straight in visual approach to Yogyakarta but continued on the ILS approach without informing ATC. As long as someone is looking out the window, there's not a lot of difference between a well-flown long straight in visual and an ILS approach, but unfortunately this was neither. The aircraft arrived overhead the initial approach fix high and fast. Not just a little bit high, but at 3927' instead of 2500'. It wouldn't be the first time a crew had cut a few corners and come in too high, but the captain, who was the pilot flying, elected to rectify the situation by lowering the nose into a steep descent. There's an expression in aviation: you can go down or slow down. They had been trying to do both for the whole descent, at one point reaching 293 knots below 10,000', knowing they had a tailwind.

The captain called for more flaps, but the first officer did not extend them because the airspeed was 33 knots over flap extension speed. The captain continued to ask for flap fifteen right through the approach, but the FO never extended them nor gave a reason why he was not doing so. The ground proximity warning system reacted to the configuration, speed and rate of descent by issuing alerts and warnings, which the crew ignored, fifteen times.

They arrived over the beginning of the runway still 89 feet in the air and travelling at 232 kts with flap 5 (as opposed to the manufacturer's recommended 134 kts with flap 40). The aircraft touched down 860 m from the threshhold (more than a third of the way along the runway), bounced twice, then landed again still well over the recommended tire speed. The nosewheel tire burst, sending up sparks as what was left of the gear scraped along the runway. Both thrust reversers were deployed, and presumably the brakes were applied, but with too much speed and too little runway remaining, the overrun was inevitable.

It does not appear that there were any mitigating issues such as approaching weather, critical fuel, or pre-existing emergency.

There are so many issues here. I'll touch responsibility, training, co-pilot assertiveness and the role of the criminal justice sytem in air safety.

The captain never took responsibility for the crash. "Lack of remorse" was even cited as a factor in his sentencing. Compare to Captains Sullenberger and Haynes who saved lives landing airplanes crippled by circumstances beyond their control, but later agonized over what they could have done better. It's almost bizarre how Komar blamed everyone and everything but himself. He attended the trial in uniform, and fully expected to return to work.

He claimed windshear at touchdown. It's a known problem in the area and something a captain with over 13,000 hours of experience should be able to recognize, but there were no other reports of windshear in the area, no indication that it might be present from the detailed winds aloft, and a professional approach marred by windshear is inconsistent with the speed profile recorded throughout the descent.

He claimed that the flaps were faulty and did not extend when selected, but investigation found "no evidence of any defect or malfunction with the aircraft or its systems that could have contributed to the accident." The chief crash investigator, Mardjono Siswosuwarno, said the aircraft's wing flaps failed to extend for landing and that might have been caused by the high speed, but that's not something the captain can blame on the flaps.

The captain also levelled blame at the co-pilot, for not lowering the flaps, and at the poor emergency services. Admittedly the copilot did not clearly refuse the flap extension command by stating "Unable, we're thirty knots high" or whatever his SOP callout was, and the emergency services at the field were poor and contributed to the death toll, but none of that excuses the captain's actions.

The PIC said that he was unaware of the actual airspeed and expected that the copilot would inform him of any speed concerns, but that doesn't align with the comments he made during the descent, or the knowledge that someone with 3700 hours on the airplane would have to possess. The copilot called for a go around before and after touchdown, and the captain did not respond. It has been suggested, (but the captain has denied) that a company incentive to save fuel led to the decision to continue the unstable approach.

Poor training probably contributes to the decisions the crew made. For example, training records showed that the pilots had attended an "introductory" GPWS course with no evidence of related sim training. Non-pilot staff seem to be lacking some basic training in public relations, seeing as they got took their pictures taken, smiling, with the burned out wreckage. But how much training does it take to choose a missed approach at some point in that accident sequence? The copilot doesn't seem to have had sim training in the actions he needed to take in order to take control of the airplane from a captain who has not stabilized the approach. He did try. He said, he had shouted at the captain to go around because "that was the proper procedure ... to ask people to go around with yelling".

And that's tough. You need training, confidence and a company culture that will support taking an airplane away from a captain. This co-pilot stuck up for the captain after the crash. I don't believe that he literally blacked out from the g-forces. I think he needs a story to tell himself to explain why he did not take control and perform the missed approach. It reminds me of Michael Origel, the co-pilot of American Airlines flight 1420 that overran the runway in Little Rock Arkansas during a landing in a thunderstorm. Origel insists that he called for a go around, despite the fact that experts can find no trace of it on the CVR. I believe him. The voice in his head screaming that this was not right was so loud that he can't believe the captain and the recording microphone didn't pick it up. Has there ever been an accident in which a copilot's loud demands that a captain go-around were cited as a cause or contributing factor? Ever hear of a copilot fired for asking a captain to go around? I can name names, hell I have a pocket in my formal coat containing funeral programmes that name names of people who might be alive today had they demanded a go around.

But considering all the things that people did or didn't do, should or shouldn't have known to do, was a criminal act committed? They broke company policy in the lack of a stabilized approach, but I don't know that they broke air regulations. Could the possibility of the CVR being introduced as testimony in court cause pilots not to admit errors in flight?

It is very uncommon for a pilot to be charged with a crime in connection with a crash. It's a somewhat disturbing precedent when you're a pilot. We're usually assumed to be doing what we believe is best for the flight, in defense our own necks, and air law gives us a lot of latitude to do things that would otherwise be against the rules to defend our safety. Any misjudgements we make already force us to face possible injury or death and then we have to defend them to our own conscience, our boss, and the aviation regulatory authority. Do we need to add the civil justice system?

The decisions the captain made during this flight seem reckless. I think his conviction is closer to the correct outcome than having the manufacturer sued for the flaps failing to deploy at excessibe speeds, but I'm not convinced that the justice system should have a role here.

Q.E.D.

A commenter recently asked about the altimeter setting and Q-codes. I have probably blogged on this before, but Blogspot doesn't show it in my archives so it's just as easy to explain again. It is to do with the way the altimeter works.

The instrument in the panel that indicates my altitude is a barometric altimeter. It operates purely by air pressure, mechanically comparing the pressure in its sealed reference capsules to the air pressure sensed immediately outside the airplane. For this purpose there are little holes on the outside of my fuselage called static ports, and tubes conduct the pressure from the static ports up to the altimeters.

As the airplane climbs, the outside air pressure drops, but the pressure inside the reference capsules stays the same and this difference moves the hands around the face of the clocklike altimeter to indicate my altitude. Electronic altimeters work the same way, except that the pressure difference is converted to a digital signal. All the altimeter knows is the difference in pressure. If the pressure goes up, the needles show a lower altitude. If the pressure goes down, the needles show a higher altitude. This also happens without the airplane ever leaving the ground, just because the air pressure changes as weather systems move through.

In order to always start at a known place, there's a knob on the altimeter that moves what the altimeter considers to be the zero altitude up or down. So you could be on the ground with the altimeter reading zero, and turn the knob so that the altimeter read a thousand feet, and then crank it back the other way so the altimeter read two hundred feet below sea level. While you turn the knob, and the altimeter hands are moving, a small dial with numbers is also moving, visible through a cutout in the face of the altimeter. On an North American altimeter the numbers usually range from 28.10 to 31.00. On a European altimeter they range from about 950 to 1050. (International altimeters have two windows and two dials driven by the same knob). Turn the knob so a bigger number appears in the window and the hands go up to indicate a higher altitude. Select a lower number in the Kollsman window and the hands point to a lower altitude. Whee! The pilot will have to set it correctly before takeoff.

But what is correctly? There are actually two systems as to what the altimeter should read when you're parked. One is that it should read zero when you're on the ground, no matter where that ground is. Under that system, a circuit pattern flown at a thousand feet above ground level would always read 1000' on the altimeter, regardless of the elevation of the airport. If the altimeter reads two hundred feet, you're two hundred feet above ground. The number that you would set in the Kollsman window to make the altimeter read zero on the ground at a particular airport is called the QFE for that airport. The QFE system is not very popular. I believe the British military uses it, as does Russia, so probably much of the former Eastern bloc. I highly doubt that a Canadian or American controller would be able to give you a QFE if you asked for one, and many probably would not understand the question. Even if you could get the QFE, there are many airports in the US where you couldn't set it on an ordinary altimeter, because the numbers in the Kollsman window don't go that high.

The far more popular way to set an altimeter is using the QNH, but North American pilots don't learn that term, either. We just call it "the altimeter setting." The altimeter setting is the number you set in the Kollsman window so that the altimeter shows airport elevation while you are on the ground. If the airport is 1200' above sea level, then the altimeter shows 1200' when you're parked, and 2200' when you're in a thousand foot circuit pattern.

Neither the QFE nor the QNH for a particular airport is fixed. It varies from hour to hour with the weather patterns. That's why the controllers and the ATIS broadcast the altimeter setting.

There's a third way to set your altimeter, which everyone does one they climb into the flight levels. That is to set 29.92 and leave it, so that you don't have to keep changing it as you go through different pressure systems en route. If there's a Q-code describing this setting I don't know it. We call it "twenty-nine nine two."

Update: The terse and anonymous first commenter below has indicated that twenty-nine nine two is called QNE. And in verifying that, I'm reminded that with 29.92 set on my altimeter, it is showing the pressure altitude but most people don't call it "setting the pressure altitude" unless they are doing it momentarily for the purpose of determining the pressure altitude for a calculation.

Injury or Death

I made someone stop and turn around so I could get a photo of this sign. I suppose there might be people who grew up on flat land with one storey underground buildings and never watched TV (or only watched Road Runner cartoons?), read books or were otherwise exposed to this concept, but wow. Does our gene pool need humans who don't equate falling over cliffs with serious injury or death?

And here's something else on the theme of injury, death and ignorance that made me laugh out loud.

Vanishing Airplane

I had an odd experience yesterday, holding at an uncontrolled airport. I taxied out in calm winds and then was asked to stay on the ground while someone in the back made a telephone call to confirm something. It's like driving a limo sometimes, except with the roar of the engines instead of the glass partition separating me from the back. While the telephone call was going on, the wind picked up and I was now at the wrong end of the runway. I was willing to take a few knots tailwind, but there were aircraft arriving so there were other safety issues involved in the runway choice. I checked with the back and they were now waiting for a call to be returned, so I had time to taxi back to the other end. I describe all this merely as preface, to indicate that I had been on frequency for a while and picked up a situational awareness for who was coming and going.

Sitting in the runup area at the correct end of the runway, with enough room for others to taxi around me if need be, I heard an airplane call inbound to the field, giving his ETE as 11 minutes. It was three minutes to nine at that point, so I wrote down his call sign and 9:07 on my kneeboard. That would give me an idea of when he was due, to help me not taxi out in front of him. A few minutes later he called again, seven minutes back. It was nine on the dot, so his ETA was unchanged. A few minutes later the cellphone conversation was over, the destination confirmed, and the cabin ready for takeoff. I called the inbound airplane by callsign for a position report. No response. Just in case I got his callsign wrong, I called again referring to him by destination and type. No response. He didn't answer on either the aerodrome frequency or 126.7. I would have seen him had he landed in front of me on the into wind runway. There was a possibility he had landed the other way, with a tailwind, but there was no taxiway between the one at the threshold, and mine. So he landed very short despite a tailwind and turned around to backtrack off the runway without making any of the required downwind, final, backtracking and clear calls? Unlikely. There would also be no advantage to backtracking: the two taxiways are equally inconveniently located to the apron.

I determined that whatever had happened to him, there was no conflicting traffic, and I took off. My current theory is that he accidentally used the wrong aerodrome name in his calls, and he was descending into some other aerodrome sharing the same frequency. Once he reached circuit altitude I stopped hearing his transmissions, and he could not hear mine.

Or he found himself suddenly in the Bermuda triangle, where he took advantage of the international card in his GPS and landed somewhere hospitable where he and his passengers are enjoying fruity drinks with umbrellas.

Our Destination Has Only One Runway

I wish to report the following four facts

• It's hard to use a computer in the back of my airplane while in flight, because it's bright and bumpy and you can't see or control the mouse pointer.
• You can't see anything useful on the ground outside from the back.
• CYMJ is not the identifier for Moose Jaw Municipal Airport.
• Canadian military controllers are very understanding of navigational errors

This is all I wish to report on this topic.

Emergency Descent

I blogged recently about the panic engendered in passengers by the standard, safest response to a depressurization incident at altitude. I'll say it again, though. The one non-standard thing that has happened is that the cabin pressure has dropped. Passengers will feel this through ears "popping" and or pain in their sinuses and ears. They probably will not notice any shortness of breath.

Then the airplane and crew reacts according to design. The oxygen masks fall from the ceiling. Everyone screams. Drop them on the ground, with the wheels on the pavement, people still scream. The homey airlines like Southwest and Westjet will even include "stop screaming" as one of the instructed steps for use of the oxygen masks.

The crew begins an emergency descent. They are getting you and your screaming lungs to a place where you can breath unhindered just as fast as human reflexes, the surrounding terrain, and the structure of the airplane allow. The rapid descent is a good thing.

I can sympathize with passengers not knowing this, and even if they do know, I can understand how unsettling a rapid descent can be. And the pain can be very severe ruptured eardrums and sinuses do heal, however, while the results of oxygen deprivation don't. It's a very easy choice.

But the media are not sealed in a rapidly descending airplane with a crew who are too busy to make a passenger announcement about what is happening. They have the opportunity to ask questions of informed people. But they prefer to just talk to the shaken passengers. So you get things like this.

Up to 26 hospitalized in forced landing in France

The terminology "forced landing" usually refers to a landing made by an aircraft that cannot sustain flight, typically one without engine power. The descent to 10,000' was forced, but that's a whacky way to describe the event. The airline says that those taken to hospital were complaining of earache, and were all released. Judging from the line in the article, "Although French officials said the plane descended 26,200 feet (8,000 meters), Ryanair gave no details about a loss of altitude," the airline should take some blame for this ridiculous article because they didn't explain the emergency descent in their press release. The reporter is left believing that the airplane malfunctioned in some way so as to suddenly drop out of the sky, and has transmitted this ignorance to the readers.

26 Hospitalized After Ryanair Jet's Midair Plunge, Emergency Landing

Emergency landing is more accurate than forced landing, but really it was an emergency descent. I wonder if they even had equipment waiting. Once again the headline describes the response to the emergency, not the actual emergency itself. Is it because the actual emergency makes a boring headline or does FOX not get it either?

I'm not saying that the reason for the depressurization might not be a serious problem. I just want the media to realize that the rapid descent is a proper response to the problem, not the problem itself. If they did report that, then perhaps the next planeload of passengers to experience a deliberate emergency descent wouldn't think they were in a death plummet.

Fuel Inerting

While discussing the recent Qantas B747 incident with some very knowledgeable pilots I learned something that bears more research, about oxygen supply and fuel inerting technology. I'll start with some background and an overview of oxygen supply options in aircraft, before I finally get to the cool stuff that I learned.

The simplest way handle the problem of ensuring people on board can breathe is for the airplane to have an unpressurized cabin and non-turbocharged engines and to be operated only at altitudes where the engines and everyone on board has access to adequate oxygen in the outside air. Pretty much everyone who learns to fly does so in an airplane this simple. It works well. The laws of physics and of the government work in concert to forbid climb beyond a safe altitude.

The next method can be retrofitted into any aircraft, and that is to carry an oxygen cylinder and masks. Gaseous oxygen is compressed into the cylinder and the flow regulated by a valve. There are various mask and flowmeter technologies to ensure comfort and efficient use of the oxygen available, and you've read about some of the ones I've used. You can also have a similar oxygen system built in, which just means that the oxygen cylinder is stowed in a custom compartment, as opposed to in the cabin. Individual occupants attach their masks to outlets throughout the cabin. It has the advantage of being integrated with cockpit systems and seeming more sophisticated to the passengers, but the disadvantages that you can't easily take the cylinder somewhere to be filled and that you're married to masks that fit the outlets that were manufactured into your airplane at the time that Galaga was the pinnacle of videogame technology.

Remember that there IS oxygen at any altitude where airplanes fly, and it is present in the same proportions everywhere. You probably already know that air is 21% oxygen, 78% nitrogen and 1% other gases. we only actually need the oxygen to breathe, the rest could be replaced with something else harmless. So that proportion of oxygen stays the same as you go up, it's just that the air at altitude is at a lower pressure, so there is less of it in the same volume. One lungful of air at 18,000' has half as many oxygen molecules as the same lungful at sea level. If there were a way to cram more of that thin air into your lungs, you would have access to just as much oxygen as at sea level. And there is: pressurization. Under normal circumstances, most high altitude aircraft pressurize the fuselage to a breathable atmosphere. It's important to realize that this isn't a matter of sealing in ground level air and keeping it from escaping. The air in the airline cabin is constantly being replaced with air from the outside, it's just that it's compressed and cooled on the way in. A significant portion of a turbine engine is dedicated to compressing air, and there's enough left over, called bleed air to power some aircraft systems and pressurize the cabin. The airplane is fitted with outflow valves to prevent overpressurization. You can sometimes hear them making horrible whistling sounds. This explains why a small hole in the fuselage doesn't cause movie-style airliner disasters: there are already holes in the fuselage to let the air out. Adding another one might make the pressurization system work a little harder, but escaping air is replaced.

Sometimes, like on the Qantas flight I mentioned, something happens to create a bigger hole in the fuselage. The pressurization system can no longer keep up with the outflow, and the airplane depressurizes. The checklist in such a case calls pilots to don their own oxygen masks and commence an emergency descent. That means they cause the airplane to descend just as fast as it structurally can. Kind of a fun one to practice! Pressurized aircraft are required to have a supplemental oxygen system in place to allow everyone to breathe during the time it takes to descend from cruise altitude to ten thousand feet, where there is breathable pressure. In an airliner, pilot emergency oxygen is always supplied from oxygen bottles, as their masks are positive pressure, designed not just to increase the partial pressure of oxygen, but to exclude noxious substances like smoke. That's because pilots have to perform useful functions in an emergency, while passengers just have to stay alive. It's fair, really.

This is all extra scary for unknowing passengers because they witness the depressurization event, probably accompanied by a loud noise. The masks drop, which despite all the safety briefings still awaken some human fright instinct based on snakes dropping out of trees. The drop in cabin pressure is such that moisture in the air may condense into mist, which looks like smoke, and then the airplane plummets. Try to keep in mind, if this happens to you, that the plummeting is deliberate and for your own good. The masks really aren't designed to muffle your screams in order to maintain the concentration of the flight crew, (but I'm not saying that might not be a useful auxiliary function) so put them on and breathe normally.

Now, what are you breathing? In a Boeing 747 you're breathing out of an oxygen bottle, just like the pilots, just with a different mask. The airplane literally contains a big bank of oxygen bottles, bristling with valves and lines running all over the cabin to the passenger oxygen masks. As you breathe in wearing one of those masks you get some cabin air and some extra oxygen from the cylinders. Ironically, it was one of those oxygen cylinders, positioned in the nose of the aircraft, that caused the Qantas decompression in the first place.

On any other airliner, you are not breathing out of a bottle, but breathing oxygen custom made for you in response to your pulling the mask towards you, as directed in the passenger briefing. The compartment above your head contains a chemical oxygen generator, based around a compound that contains oxygen, in the same way that H₂O contains oxygen, but less stable. It takes a lot of energy to liberate oxygen from water, but just ignite something like sodium peroxide (Na₂O₂) and it starts to decompose. Na is elemental sodium, O is oxygen, and it takes two oxygen atoms to make oxygen gas (O₂). The sodium peroxide breaks down into sodium oxide (Na₂O) and releases oxygen gas. Here's the equation.

2 Na₂O₂ --> 2 Na₂O + O₂

You don't have to have understood high school chemistry to count that up and see that there are two Na atoms and 4 O atoms on each side of the equation, with nothing left over. Now, that's pretty neat if you can get around the bit I skimmed over and that is that in order to start this reaction, you set the oxygen generating chemical on fire. When you pull the mask briskly towards you, you are pulling a pin to fire an ignitor. You may even smell it burning. But despite the scary sounding implications, they are maintenance free devices. The only incident I know of where chemical oxygen generators caused a fire ValueJet where a number of the devices were being transported in the cargo hold, mistakenly labelled empty. They should have been deactivated for the flight. A real drawback of chemical oxygen generation is that it is a short lived system capable of putting out about 12 minutes of oxygen, just enough to get down to 10,000'. For flight in areas with a lot of high terrain, supplemental gaseous oxygen is required. Boeing offers this as an option on the B737NG and as a retrofit on other aircraft.

It would be nice to have oxygen available that didn't have to be held in either a pressurized container or an unstable chemical compound. And there is. In the air. There exists technology to separate nitrogen from oxygen in the ambient air. While the unpressurized air at 30,000' doesn't contain enough partial pressure of oxygen to sustain consciousness, the same pressure of close to 100% oxygen does. And the cool part is that generation of oxygen in this manner is just a side effect of fuel tank inerting.

See, when an airplane takes off, typically the tanks are full of fuel. In the absence of fuel tank inerting, as the fuel is burned, the resulting space (cool word alert: it's called the ullage) is filled by ambient temperature air and fuel vapour. Given the right conditions, this mixture of fuel vapour and air can ignite, to disastrous consequences. The idea behind fuel inerting is to fill the fuel tank ullage with something inert. Like nitrogen. And now if you didn't already, you see where this all comes together. During the flight, take the air that is already going by anyway, and make almost pure nitrogen, used to fill the unused space in the fuel tanks, and then have close to pure oxygen as a byproduct. I don't know much about the actual system that will be on the B787 Dreamliner, but apparently the whole apparatus weighs about as much as one passenger with luggage, and draws 40 kW of power.

The Boeing 787 will use this system. The B787 will also make a liar out of me for what I said about bleed air, but this post is about the fuel inerting. It's so symmetrically beneficial, it's almost as if putting my laundry in the washing machine somehow created both clean underwear and groceries.

Clunk, Part II

For best results, read Clunk, Part I first.

There continue to be no control difficulties, engine changes, or airframe flutter and I decide against an immediate precautionary landing. Or maybe I just haven't decided to make one yet. Absence of a decision is a decision, after all. There are as many good sites to land ahead as there are in the immediate vicinity, and the larger airport at our intended destination is in a larger town, with more resources, if we need anything. I'm trying to think of the most dire thing that this could be. Parts falling off are going to make a distant and inaudible thud or splash, not a clunk. And the moving parts on this bird are mostly fabric. They simply aren't heavy enough to clunk.

I know that there are some springs securing the rear of the exhaust system to the front of the exhaust system, and that they are a bit of a weak point. While Lite Flyer was up on her test flight at the manufacturer's I had a look at their demo plane, and noticed that it had a one-piece exhaust system. "There are no springs on this one," I said to the wiring expert who was with me.

"Yeah, springs break and go through propellers," he said. "This is the new improved kind."

The springs on this one are all safety wired and have that orange gunk on them that you use to tell if a nut is starting to back off a bolt. They were all intact and wired down before this flight. But maybe under the right conditions a spring can make a heavy clunk. Aviatrix, who knows perfectly well that springs go sproing tries to rationalize. If something had hit the delicate little composite propeller I'd expect an engine vibration. If I really thought it was a spring, I'd be landing already, because if one goes, then there's more strain on the others.

While I'm thinking, I reach in the side pocket by my seat for my water bottle. I heard once that even two per cent dehydration has a measurable effect on cognitive ability. But damn: my water bottle is not there. Did I leave it in the FBO when I refilled it? No I didn't. I reach down behind my seat, down in front of the fuel tank. I find my water bottle. You might recall from an earlier posting that I eschew plastic water bottles and have invested in metal ones. The kind that go clunk when you drop them against a fibreglass-kevlar hull. "Listen to this," I say to Lite Flyer, and I drop the water bottle again.

Clunk.

Mystery solved. In the best possible way. My mouth went dry because while I can reach my hand back there and grab the water bottle, the space my hand goes through isn't big enough to pull the water bottle out through. It's like trying to get a pop out of an old fashioned ice-chest style pop machine where you have to pull it along to the right spot after you put the coins in.

I could tell you about the rest of that flight, but it would be an anti-climax, wouldn't it. And you've probably stopped reading already to berate me for stringing you along. So I'll wrap it up quickly. New Hampshire became Maine under our wings, and other than finally descending to a right-way altitude of 3500', we stayed high because there are a large number of very tall towers in that part of Maine. We tuned up the ASOS for KLEW and it favoured a landing on the small cross runway, but there was a lot of traffic on a crossing runway, which curiously is zero four. I say curiously, because this is still the United States and these are American accents in US-registered airplanes, but they are saying "zero four" not just four. Everyone is doing it. Must be the Canadian influence. I don't believe the US has decided to conform to ICAO runway numbering overnight.

I hear student pilot radio voices and instructor radio voices. Three airplanes are doing continuous circuits and other traffic is departing and arriving, probably from the local practice area. While I could arrange our approach to go under the downwind, it could be tricky to coordinate crossing an active runway with different speed traffic. With it being busy and having students around i want to do the most expected thing. I direct Lite Flyer to fly towards a point that will allow us to join "downwind on the forty-five," the most common US pattern entry. I think she is confused why I am sending her the wrong way, but I don't spend the words explaining, because I am listening to overly verbose student pilot radio calls, and looking out for traffic, trying to make sure I don't cut anyone off. We join, fly a close-in circuit and I take control to sideslip us in and clear the runway. There are a lot of GA aircraft here and I park in an unoccupied space and then go back to the flying school to confirm we're okay there overnight.

We take on the usual division of labour, with me securing and inspecting the airplane while Lite Flyer goes to convince strangers to help her get mogas. She's good at that.

We Control the Vertical

A two-axis autopilot has capability to control pitch as well as roll, which means that it can be used to hold altitude not just heading. There are different ways this is implemented.

The big difference is in whether your autopilot has the altitude capture feature or not. If it does, you can tell your autopilot to "climb to such and such an altitude and then level off." There is usually a part of the autopilot console where you can set the target altitude. The autopilot knows to reduce its rate of climb or descent approaching that altitude. As the pilot, you need to ensure the correct power setting for the task; it's not an autothrottle and you don't want to be diving at high speeds, nor pitching up for a climb with decaying low speed.

If your autopilot does not have altitude capture, as this one doesn't, you have to wait until you're just about at the target altitude, considering the rate of climb or descent, and hit the ALT mode button at just the right moment. You may coast past and have to fix it afterwards, or you may have a habit like the one I'm trying to break, and just disengage the autopilot, level off manually, and then hit autopilot hold. I have this habit because the autopilot controls by motoring the trim, not by physically moving the yoke and hence elevator the way I do, and the effect of one airplane I fly trying to level the airplane with elevator trim is seriously sick-making. When the plane makes the pilot wonder if she can reach the vomit bags from her seat, it's worth hitting the red switch.

If you're flying level at one altitude and want to descend, there's two ways to do it. One is to leave the ALT mode engaged and to press on the vertical trim switch, not the electric elevator trim on the yoke, but a switch on the autopilot control box, and that will give a climb or descent of up to 600 fpm, while you are holding it. Or if you want a faster descent, you press the autopilot ALT button, disengaging that mode, descend like a normal person, and re-engage the ALT hold when you're at the altitude you want to hold. You can, of course, leave the heading mode on during the descent, so that the autopilot controls straight line flight and you control the climb or descent.

This engaging and disengaging makes for fun times, because to disengage the autopilot I am used to, you can press the big red autopilot disconnect button on the yoke, or just apply pressure to the yoke. As soon as there's a disagreement between what I'm telling the airplane and what the autopilot is telling it, that autopilot surrenders and gives control over to me. This particular autopilot, however, has much more confidence in itself. If I apply pressure to the yoke without disengaging the autopilot, it trims against me. And it will continue to trim against the force I exert until it runs out of trim, or I give up. At that point the control forces exerted by the trim may be more than the autopilot can handle, causing it to disengage, and leaving me having to exert fifty pounds of control force while retrimming. The fifty pounds figure is from the manual, not personal experience. I'm sure I didn't ever get much beyond twenty-five pounds before remembering to hit the disengage switch. From now on, I plan to use the disengage switch every time so I'm ready for either sort.

The way I fly without an autopilot, the descent rate depends on the power setting and the speed remains the same, unless I deliberately trim nose down to get a higher speed in the descent. During the training on one approach I didn't bring the power back enough because I'd started the descent on autopilot, and my speed was too high for my approach timing. I resolved to reduce the power before asking the autopilot to descend, just as I would if I were asking for the descent with the yoke, even though the training pilot did it the other way around.

It seems like quite a lot of bother to avoid having to fly the airplane, doesn't it?

Caught in the Rail

I had a new thing happen on a flight today. Not amazingly exciting; not even a little bit exciting, really. Just a matter of "heh, never saw that before." I guess the world never runs out of things to throw at pilots.

It was a routine flight, one other crewmember on board, good weather, no problems with any of my equipment, and the mission was complete. Close to destination, I started my descent checks, which includes a seatbelt check. My crewmate informs me that his seatbelt is stuck. He can't put it on. "Did you move your seat forward?" I ask. I tell him how to move the seat back again. But he didn't move the seat. And moving it doesn't help.

This is weird enough that I wouldn't quite believe him, but he's very conscientious and has always demonstrated excellent problem solving skills, so I do believe him. And he solves this problem himself too. The cockpit seat next to me is empty except for my gear. I put my flight bag on the floor and he comes up and sits in the front. I give him the mini-briefing on the shoulder harness and cockpit safety gear and we're good to land. This airplane tends towards being nose heavy, but we've burned enough fuel that this movement of weight can't put me out of the legal envelope.

I ask him to flick a couple of switches for me, to save me leaning across him, and he likes that, so I give him control for a bit. Whee. Better not let him fly too long or he'll realize what a great job I have. I take control back on downwind and skid us around (in other contexts bad pilot technique, here an operational requirement) for landing.

On the ground he goes to the terminal to get us a ride and I inspect the seat and seatbelt. The seatbelt is exactly like the one in an old car, the "lift flap to release" sort, not the newer "push button to release" kind. That doesn't actually matter, because the buckle itself is fine. It's the loose end, the part that sticks out of the buckle and that you pull on to tighten your seatbelt that has a problem. You know how at the very end of the belt, it's folded over and stitched? But it's folded over twice so that the frayed end is hidden under the stitching, and the stitching isn't at the very point of the fold? Thus because of the folded over stitched part, the end of the seatbelt is a tiny bit like a hook. I guess that's deliberate so that the end doesn't pull through and allow the buckle to fall off, when you make the seatbelt as big as it goes. When my co-worker unfastened his seatbelt in cruise (he has to move around the cabin to work), the end just happened to fall in a way that allowed it to poke up inside the channelled claw of the seat that grips the seat rails. And because the end is folded back on itself, it acted like a barbed fish hook and wouldn't come back out. I pull it back and forth and sideways, but it is in there. I have to get a screwdriver, and take the cap off the end of the rail so I can slide the seat off the rail, in order to extricate the belt end.

And then I put it all back together again and double check to ensure the seat is safely anchored. I fasten the seatbelt across the seat as I was taught to for neatness and to prevent damage from people stepping on them. Now there's another reason.

Update: Yellowbird has skillfully identified the aviation movie that so puzzled me while I sat blogging in Montana. It's called Warbirds, and you should read his summary and review of the hilariously unexpected plot in his comment on that entry. I'm still laughing.

Yellowbird's blog stands out from other private pilot blogs because he owns the airplane, so blogs in detail not so much about slipping the surly bonds, but about the labour of love that goes into maintaining that airplane. He explains, for example, how to inspect the contents of your oil filter, in your kitchen, with separate advice for married people. Not a frequent updater, but well-written entries from someone who knows how his airplane is put together.

Le Grand Saut

About the time Blogger autoposts this timestamped entry, and if the surface winds are low, a man named Michel Fournier is riding a balloon-lifted capsule, preparing to jump out 130,000 feet above southwestern Saskatchewan. He has a parachute, but he doesn't plan to open it until he has fallen to five thousand feet above the North Battleford farmland. He is attempting to break the records for the longest freefall descent and the fastest human-only travel, and more importantly to prove that high altitude ejection is viable for spacecraft encountering re-entry difficulties.

Fournier refers to it as "un projet ancien francais," as the European space agency was working on such an ejection system for their shuttle, and Fournier was scheduled to make a test jump in the late 1980s. But the jump was cancelled with the European shuttle program, and the French government refused him permission to try the jump on his own, with other sponsors. The Canadian government said yes, selecting the area around North Battleford as having few lakes in which an unconscious jumper might drown, and pretty much nothing to hit. I've flown there, and while it's not the most desolate piece of country I've ever seen, I have to agree that there is not a lot to hit.

There's no NOTAM out yet for either a high-altitude skyjumper or balloon. I suppose that would defeat their stated plan to keep the planned landing location secret to prevent anyone interfering with the recovery operation.

Here is the English version of Fournier's own website on the project. Presumably that will be updated to announce if he goes on Monday. There are articles about the jump in the New York Times and at France24.

This is Fournier's third attempt, so I guess the adage about "try, try, again" does apply to parachutists, after all.