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Piper_Driver
30th Sep 2009, 20:27
This is a breaking story out of Indiana. Looks like a Mooney pilot lost conciousness and was shadowed by an F16 for about an hour before augering in.

Small plane crashes in eastern Indiana field - Yahoo! News (http://news.yahoo.com/s/ap/20090930/ap_on_re_us/us_small_plane)

Fortuneately no one on the ground was hurt. Condolences to the pilot's family.

RTN11
30th Sep 2009, 21:58
25,000 feet is very high for a mooney. Sounds like he was trying to fly as high as possible, then passed out, the plane kept climing then entered a spiral dive.

I'm sure a lot of pilots go above 10,000 feet, or even 14,000 without oxygen. It's a tricky subject. It's not like as soon as you go about 14,000 you will pass out, but you do need to keep track of how long you've been at such a high altitude.

I may think twice the next time i'm tempted to try and find the absolute ceiling for an aircraft.

Pace
30th Sep 2009, 22:37
I have flown a Piper Seneca Five at FL230 on oxygen. On the Five I was still seeing 800 fpm passing 20000 feet yet the service ceiling is quoted as 25000 feet. I have heard of a Piper Seneca Five topping nearly 30,000 feet in the right conditions.

Beyond quoted service ceilings is possible be interesting to know what others have been up to in their aircraft? and the highest you have been unpressurised on oxygen.

in this situation there is no reference to the flight being a record attempt or the reasons for the pilot being incapacitated which could have been something other than lack of oxygen.

Also to consider are air conditions which could have lifted the aircraft to those levels which is a very real possibility.

Pace

Pace
30th Sep 2009, 23:44
As he was in Class A airspace it should not be so difficult for the authorities to confirm as to how he ended up at FL250.

SoCal

The fact he was in class A suggests that it was not some sort of altitude attempt and unlikely to have been a requested cruise level.
It is possible he was lifted up there. I can remember flying in a Citation 2 to Nice.

There were warnings of severe turbulence between FL290 and FL240. I warned the pax, reduced speed and expected the worst only to be embarassed by silky smooth air to a Nice landing.

Leaving for the UK now empty and taking the more northerly departure over the Alps climbing through FL240 all hell let loose. 45 degree wing drops, items flying around the cabin, severe turbulence like I had never experienced. The jet was almost uncontrollable. Asked for an immediate climb to FL320. at FL240 the Citation 2 normally climbs at around 1000 fpm I had 4000 fpm all the way to smooth air at FL320.

This poor guy was hardly up there in a mooney by choice? any other ideas as lift could be one theory?

Pace

Pace
1st Oct 2009, 07:12
SoCal

Just discovered this was a turbocharged 270 HP Mooney Bravo with a service ceiling of 25000 feet. It is therefore very likely that he was cruising at FL250 and either ran out of oxygen or had a supply problem.

Having said that not all pilots would pass out at 25000 feet although their judgement would be severly impaired, smokers I beleive are at 5000 feet higher than non smokers so equivalent of 30K if a smoker. In tests in a pressure chamber some passed out at 25K others didnt with many factors effecting who did or didnt.

Pace

Katamarino
1st Oct 2009, 09:36
Good to see they got in the obligatory reference to panicking school children.

Runaway Gun
1st Oct 2009, 09:39
Pace, everyone would pass out at 25,000 feet.

Even if Superman was a smoker - so would he.

Pace
1st Oct 2009, 09:52
Pace, everyone would pass out at 25,000 feet.
Even if Superman was a smoker - so would he.

Runaway Gun

Not so ! climbers have climbed mountains higher than that without oxygen and with exertion which pilots dont have although I add they are conditioned to it first.

I have taken my oxygen mask off for short periods at 20K and once ran out of oxygen in 70 kt headwinds over the alps at X :) for a short time.

While I agree plus 30K you have had it 25 K is marginal and depends on your fitness, Whether you compress breathe, your lung capacity, how tired you are, whether your a smoker, your weight, general health etc as well as how long you are there.

But in tests not all pass out at 25 K

Have a read of this extract from a test pilot of old it makes interesting reading

1943 | 1754 | Flight Archive (http://www.flightglobal.com/pdfarchive/view/1943/1943%20-%201754.html)

Pace

chrisN
1st Oct 2009, 10:11
Pace; " , , , over the Alps climbing through FL240 all hell let loose. 45 degree wing drops, items flying around the cabin, severe turbulence like I had never experienced. The jet was almost uncontrollable. Asked for an immediate climb to FL320. at FL240 the Citation 2 normally climbs at around 1000 fpm I had 4000 fpm all the way to smooth air at FL320."

Sounds like classic mountain wave - in the rotor at first, then into the smooth lift. But I expect you knew that.

In a glider, getting into wave is eerie - the smoothness and silence are awesome. AIUI, the air mass goes into laminar flow.

Returning to the original incident, or rather to cases which might arise like it (as I don’t have any more facts about the event in question), it is quite possible to fly straight and level into a continuous band of rising air which adds several hundred, or even a thousand or more, feet per minute to whatever one was trimmed for in still air. Wave bars can run for many miles. In Scotland last year, a glider pilot did over 1500km in one day using wave bars, but mainly staying at intermediate levels and using the energy to fly fast rather than climb.

Chris N. (edited to add last paragraph.)

englishal
1st Oct 2009, 10:17
My dad used to regularly decompress navy pilots to 25000' and they would swear blind they never passed out...until they opened their shirts to find all the writing on their chests ;) Something I want to try one day, maybe when I visit the USA I can find somewhere. Not heard about anywhere in the UK that offers this service to private individuals.

But I agree, not everyone would pass out, people survive for days at > 25000, but these tend to be the fit, mountain climbing types, not pilots :)

By the way the 250000 ceiling is just an FAA number as this prevents having to have the high altitude endorsement to fly the aeroplane at any height. Likely the TC'd mooney could reach much higher.

IO540
1st Oct 2009, 10:25
25,000 feet is very high for a mooney. Sounds like he was trying to fly as high as possible, then passed out, the plane kept climing then entered a spiral dive.

I'm sure a lot of pilots go above 10,000 feet, or even 14,000 without oxygen. It's a tricky subject. It's not like as soon as you go about 14,000 you will pass out, but you do need to keep track of how long you've been at such a high altitude.

I may think twice the next time i'm tempted to try and find the absolute ceiling for an aircraft.25k is a normal ceiling for a decent turbocharged IFR tourer.

I fly a TB20 which is non-turbo and has a 20k ceiling and I've been up there a few times, and routinely go to 18k or 19k as necessary to remain VMC above weather. Recently I had to sit for 6 hours at 18-19k, to stay above weather.

This pilot would definitely be on oxygen.

His oxygen may have run out (you will need a LOT of it at 25k, using a mask; he would have had a fitted o2 system but regular flights at 25k will deplete the cylinder pretty quick, and refills are not available everywhere, even in the USA), his 1st stage regulator or demand regulator may have failed (there is a well known brand of electronic demand reg which fails SHUT when the battery goes flat, although it does give you lots of audio warnings), or of course he may have become otherwise incapacitated.

At 20k, one merely needs to stop breathing for say 20 secs it takes to do a long ATC readback and one feels the need for another good long sniff. At 25k, any oxygen issue and you will be out of it pretty fast.

I don't think one could get a non-turbo plane (with typ. a 20k ceiling) to go to 25k. The engine would not be making anywhere near enough power to stay above Vs. I reckon my TB20 would make 21-22k absolute max, at the lowest possible weight. The plane flies just fine (the turbocharged TB21 will make 25k) but engine just runs out of steam, and you stall. I've tested this a few times. If the pilot was unconscious when this happens, one would be in a spiral dive more or less instantly because no plane will recover from a stall by itself with wings level and keeping them level, and no normal plane will recover to wings-level from a major roll axis disturbance in the absence of a pilot. Also the autopilot (if used) would have wound the pitch trim all the way back, to maintain altitude (or VS, or whatever was the target) so when the full stall actually occurs, the nose isn't going to conveniently pitch down to let the speed build up (Turkish 737 at Amsterdam e.g.) because the plane has already been trimmed for Vs.

IMHO, pilots who fly IFR (airways) without oxygen are less than smart. At typical European airway MEAs (FL100 is where the routings start to work OK) not only are they not functioning optimally (esp. during a long flight) and arrive knackered, but they are also cutting off a huge portion of their operating ceiling, which is by far their best weather handling strategy. A portable o2 kit cost peanuts, relatively.

Oxygen is desirable at 10k for long periods, 13k for almost any time, 15k absolutely, and at 18k few pilots would be functioning. At 25k nobody would be functioning (not saying they would pass out totally) after some minutes and looking at the average GA pilot fitness probably a lot sooner.

ot so ! climbers have climbed mountains higher than that without oxygen and with exertion which pilots dont have.Mountain climbers go up slowly, over days, and all the serious ones are super fit. Even climbing that little hill called Kilimanjaro (19.7k) which is just a straight walk up a path, people just manage it over 3-4 days on the way up, with a few hard core types doing it over 1 day. But a turbo Mooney can get to 25k in half an hour.

Pace
1st Oct 2009, 11:46
10540

I am not saying you can fly along at 25 K without oxygen. I am saying that in pressure chamber tests not all pass out maybe 50% at that level.

I am also not saying that those who do not pass out would be wired up correctly :)

In the link to the test pilot article I posted you will see that he often flew to 18000/19000 feet without oxygen and on one occasion above 20K.

I think it is more than likely that this pilot passed out maybe unaware that he had NO oxygen feeding his mask at 25 K. One strange point is airways he is unlikely to have been hand flying and would have been on autopilot. The Bravo is ultra stable even off auto.

You would have thought that passing out the plane would have flown along until the fuel ran out at its programmed level?

I would also agree that at 10/12K it is a good idea to whiff some oxygen now and again to keep you sharp and especially before a night approach.

Pace

mm_flynn
1st Oct 2009, 11:49
The recommendations I have seen for O2 flying at c FL250 seems to suggest hyper-alertness to pins and needles, headache, numbness and a frequent check on your pulse oximeter. I too have found that talking to ATC puts a drain on the O2 sat and have a basic mask with the mic penetrating so that I can keep breathing when talking.

FL190/FL220 seems much more manageable and you are that much closer to air if something goes wrong on the O2 delivery.

I don't know about the Mooney Bravo, but the TNIO-550 in the Bonanza (a broadly similar configuration) will maintain 30 in MP all the way to the certified ceiling of FL250 as long as you are turning more than 2500/2600 rpm. In any event, he almost surely had planned the flight at, or consciously climbed to FL250 and then had a problem.

Runaway Gun
1st Oct 2009, 11:52
Sure, mountain climbers require aclimatisation to ascend to great heights.
This takes days, even weeks, and even then, the individual might not succeed.

Every time I've been in the Hypobaric Chamber, and I've probably done a dozen runs at altitude without oxygen now, I've lasted less than 4 mins before requiring assistance (whether that was deciding to put on my mask, or requiring help from another - which is normally wiped from my memory). And that was whilst on 100% Oxygen during the climb. And I'm pretty average, meaning others last less, and others have lasted maybe a minute or two longer.

The rapid decompressions are even more fun, actually alarming, but if you're about to eat I won't go into that right now. :ok:

IO540
1st Oct 2009, 11:57
You would have thought that passing out the plane would have flown along until the fuel ran out at its programmed level?

The report states

A single-engine plane crashed into an Indiana field on Wednesday after the pilot, who was seen slumped over, lost consciousness and the aircraft started flying out of control, officials said. Military officials do not believe the crash was terrorism-related but said the pilot may have had a health problem or have been suffering from a lack of oxygen. After air traffic controllers lost contact with the pilot, F-16s from Indiana National Guard intercepted the plane and followed it for about an hour until it crashed.
which suggests he was on autopilot, otherwise the F16 would not have been having a look for long enough to see him slumped at the controls. A spiral dive will always take place pretty fast, in the absence of roll axis input. 1 hr is far too long.

Re the pilot in your 1943 report, I think this just proves that it can be done (20k without o2) but would you want to try it? That was a different era, when men were men, girls were girls, and life was real :) And if something needed to be done, a real man was on hand to go and do it. And if he didn't come back, a telegram got sent to his last known address...

Pace
1st Oct 2009, 12:00
Runaway Gun

Ok :) wont fight you on it! Got to shoot off now anyway.

Have to meet my mate Robin for a luch time drink and the Batmobile will get a parking ticket if I leave it much longer and dont move it :E


when men were men, girls were girls, and life was real And if something needed to be done, a real man was on hand to go and do it.

10540 and now Men are Girls, Girls are men and a real Man gets ????
:O

Pace

mm_flynn
1st Oct 2009, 12:05
The report states

F-16s from Indiana National Guard[/I] intercepted the plane and followed it for about an hour until it crashed.
Is the most important line

Allowing time for the problem to develop, for ATC to notice the pilot not responding, ATC to then decide they have an emergency and ask for fighters, Fighters to scramble, get there and observe for an hour ... sounds like more than enough to run out of fuel. The A/P would then wind in a fair amount of trim before it disengaged and the aircraft would develop a spiral at modest speed above stall.

This clearly lasted long enough to identify where it was likely to crash and implement the 'get everyone inside' strategy.


All very consistent with an O2 failure at altitude while on autopilot.

IO540
1st Oct 2009, 12:15
Yes, upon a sudden fuel exhaustion the AP would wind the trim back for the certified limit of 16 (??) seconds before disconnecting.

Girls are men

Only at LGMT :)

Runaway Gun
1st Oct 2009, 12:16
Sorry Pace, I only just saw the link you posted which was very interesting reading.

The author did state he flew up 18,000 ft maybe 8 times per day, and that it was tiring and he knew his test figures were not accurate. Sounds like he did indeed have a pretty good tolerance, and it also appears that he was a little aclimatised from his regular climbs. Even his climb to 20,000ft sounds pretty dodgy - I doubt he stayed up there for very long. I particularly enjoyed his reference to drag on a cigar at 20,000ft.

I've been fortunate to have experienced hypoxia many times, fortunate only that it was in a controlled environment, with a Doctor present. The effects for me are confusion, difficulty with basic maths, poor memory, selective hearing (my ex-wife could have already couched for those points). I also noticed a slight tingling in my fingertips, and most scarily, a euphoric feeling. And then the shakes. In fact I felt great - why are those other guys puting their masks on, when I've never felt so great? I likened it to having my drinks spiked with very strong alcohol without my knowledge. The worst point is though, that sometimes I can catch it, and decide when I need to put on my mask, and hopefully actually achieve it. Other times though - no good, I simply would have collapsed.

Another scary aspect is when the 100% oxygen is placed back on, the hypoxic effects actually worsen initially, with some users actually trying to again remove their masks.

Only once to my knowledge have I experienced this in an aircraft. just the initial symptoms, including tingling in fingertips and lips. I voiced my concerns and the flying pilot decended. Once on the ground we discussed it, and turned out that he knew nothing about hypoxia. He probably concluded that I was just a bit of a girl...

Pace
1st Oct 2009, 12:36
Runaway Gun

Nowadays I am happy at up to 14 K without oxygen but in the past did have a nasty situation in the very high teens over the Alps where I could not descend ran out of oxygen partially due to a leak and very strong unforecast headwinds. I had No choice but to stay there till the terrain lowered ( am still here although the girlfriend argues that point with me sometimes :O )

Tolerance is a very individual thing

Take care

Pace

B2N2
1st Oct 2009, 13:22
That would be the second SE oxygen related crash in a short period of time:
ERA09FA429 (http://ntsb.gov/ntsb/brief.asp?ev_id=20090731X10108&key=1)

IO540
1st Oct 2009, 13:55
Scary. And this is after that 737 over Greece...

What kind of an oxygen system does the SR22 have? Is it constant flow, or with a demand reg?

Pace
1st Oct 2009, 15:21
B2N2

Very Sad reading this report. What a shame he never used the shute when things got bad.

Interesting on our last discussion on pilots passing out at 25000 feet was that he survived nearly an hour in reduced control of his aircraft at altitudes up to 26000 feet and most of that time at 25000 feet and managed ATC communications albeit confused.

What is abvious is that up to 20K you have a reasonable chance if you dont smoke and are in reasonable nick over 20K and your on a slippery slope if the oxy system goes wrong.

Pace

IO540
1st Oct 2009, 15:39
If these are what "we" think they are, i.e. oxygen failure without the pilot realising it, maybe the problem is that some pilots are flying without monitoring their oxygen levels.

It is probably easy enough to lose oxygen without realising it.

That 737 over Greece managed it perfectly well without either "professional" pilot suspecting a thing, despite cabin altitude warnings going off everywhere.

In a GA cockpit, in an old-style fitted system (as is typically found in turbocharged planes) the cannula or mask just plugs into a bulkhead-style connector / variable-orifice flow restrictor, which is fed with a constant pressure (about 20psi) from a first-stage regulator which is located somewhere near the cylinder in the boot. If you stop sucking the oxygen, there is no warning.

And most turbocharged pilots will just be using the default provided system. I bet most of them will have never heard of anything else. This may be more true of the Cirrus customer base, due to their innovative (not intending this in any sarcastic way) marketing.

With the Mountain High electronic demand reg, if you stop breathing, after a while you get an audio warning, but if you merely breathe lazily (which at 25k won't be good enough) you won't get the warning.

With the Precise Flow demand reg (which I have) you hear only the distinct hiss of the oxygen pulse as you inhale, but there is no warning as such if you stop breathing.

This kind of thing could get any of us, and could catch anybody flying at 25k in one of the old-style fitted oxygen systems unless they watch their blood oxygen level carefully.

The problem is they have no backup - other than a rapid descent which isn't going to be an attractive option if there is nasty stuff below, which is probably why you were at 25k in the first place :)

I don't have a backup for a first-stage regulator failure for example... it's not really practical.

Pace
1st Oct 2009, 17:37
other than a rapid descent which isn't going to be an attractive option if there is nasty stuff below, which is probably why you were at 25k in the first place

10540

You have to question why a pilot would want to struggle up to FL250 in the first place in a non pressurised piston single.

In Europe even over the Alps you wouldnt need FL250 to cross the Alps other than in strong winds.

The usual reasons are crossing high mountains, clearing weather although FL250 wont get you on top of a lot of Cbs. Getting above the icing levels in the summer months. In winter FL180/190 would do that. Staying in certain airways. Getting the best tailwinds? maybe. Clearing turbulent layers (maybe).

Really unless I am missing something there are not many occasions where FL180 one way and FL190 the other wont achieve what you want in an unpressurised single engine piston.

At those levels you shouldnt come to much harm on oxygen even if the system or supply failed.

Pace

Runaway Gun
1st Oct 2009, 18:14
I'm still concerned about the attitude/belief that up to 20,000 feet you have a reasonable chance. Incorrect.

There's a great article to read here:
SKYbrary - Hypoxia (OGHFA BN) (http://www.skybrary.aero/index.php/Hypoxia_%28OGHFA_BN%29)

In particular, I'd like to emphasise the following:

Critical Stage, above 5,500 m (18,000 ft)

Above this altitude, complete incapacitation can occur with little or no warning. All senses fail, and a pilot will become unconscious within a very short period of time. No stimuli such as the radio will be able to help a pilot suffering from hypoxia, especially fulminant hypoxia, above 5,500 meters (18,000 feet).


Also note that the Time Of Useful Consciousness tables are for Rapid Decompression cases, and do not include the scenario of climbing to altitude with the gradual degredation of oxygen throughout the climb. Pilots can pass out during the climb to height !!

IO540
1st Oct 2009, 18:44
Pace,

You have to question why a pilot would want to struggle up to FL250 in the first place in a non pressurised piston single.

The tongue in cheek reply would be that the sales brochures for all these planes quote the fantastic headline TAS figures at FL250, so the pilot was only doing that, and doing it within the certified envelope ;)

The sensible reply might be that if you really like cruising at 75% to 85% power, and are aware that your engine probably won't make TBO (few turbo engines do), then why not? You get the highest TAS up there. A lot of SE pistons do 200kt plus up there. I think even the TB21 almost does that, somewhere above FL200. The oxygen usage will be high but we don't know how often he was doing this; probably not often.

In Europe even over the Alps you wouldnt need FL250 to cross the Alps other than in strong winds.

It is true that stratus cloud is very rarely above FL180. But the other week I did a 6hr20m flight (UK to Croatia) wholly at FL180/FL190 just to stay on top, and there was no frontal weather around. FL160-180 is pretty common.

A lot of warm front weather has tops close to FL250. I always cancel those flights.

FL250 capability would be dead handy to have, and would improve my "despatch rate" from say 75% to maybe 90% because most warm fronts can be crossed at FL250. Not CBs of course but the whole idea of flying high is to be VMC on top so one can visually avoid anything sticking up.

The only reason I have not bought a TB21 yet is because due to the lower compression it is about 10% less efficient (MPG) which impacts the range, and if I fly it "as intended" it won't make TBO i.e. 10 grand to pay at the halfway stage. Plus the lower payload... plus some engine downtime stories due to turbo issues...

Staying in certain airways.

It is true that Eurocontrol routings get a whole lot more interesting at FL200+ (upper airways are a lot more straight). I have never filed that because at FL200 I have to run at max RPM so the SFC is not as good as FL180. But these accidents were in the USA where they don't have this stuff.

Getting the best tailwinds? maybe.

If you have a tailwind, sure. But it doesn't improve much from say FL180 to FL250.

Really unless I am missing something there are not many occasions where FL180 one way and FL190 the other wont achieve what you want in an unpressurised single engine piston.

Just unstable weather, and less than violent frontal weather.

At those levels you shouldnt come to much harm on oxygen even if the system or supply failed.

I think one would have to make some fast decisions though.

There are passengers too, possibly.

007helicopter
1st Oct 2009, 18:52
What kind of an oxygen system does the SR22 have? Is it constant flow, or with a demand reg?

This particular Cirrus N408CD had the Mountain High MH O2 system with an audible alarm. The pilot was Chuck Huff a very experienced CSIP instructor.

Pace
1st Oct 2009, 19:30
Runaway Gun

The comments up to FL200 meant in comparison to FL200 up to FL250.

I would rather have an Oxygen failure below FL200 than above :eek:

At FL180/190 if your oxygen supply failed you would stand a reasonable chance of being wired up well enough to descend to more favourable levels.

I am not a scientist but would imagine that if you are reasonably fit your not going to black out at those levels over a short time and should have enough brain power to get the aircraft down in reasonable shape. If you do black out after a short period something is seriously wrong. I knew a Glider pilot who had problems at 8000 feet but then he puffed through 40 fags a day.
In the accident report on the Cirrus above the pilot lasted nearly an hour at FL250/260. How would he have been at FL180/190?

Life is a risk and the only way to avoid that risk is to refuse to fly at levels where you need an oxygen supply. Any level over the universally accepted 10000 feet (Americans say higher) is a risk and mechanical things do break or go wrong.

Maybe any high level flights in non pressurised aircraft with oxygen should be avoided until more fail safe methods of supplying oxygen and monitoring the oxygen transfer are invented.

Otherwise we either take a risk or stay at home in bed. :sad:

Pace

Molesworth 1
1st Oct 2009, 20:39
Nothing to see up there in any case.

Fly-by-Wife
1st Oct 2009, 21:24
It is possible to acclimatise to operating at high altitude without oxygen.

WW1 pilots operated regularly up to 22,000 feet in open-cockpit biplanes without oxygen, and often flew for up to 2 hours above 18,000 feet. They were very young and fit, though! Even so, it is clear from their accounts that it was physically punishing, especially in winter.

Mountaineers also are able to operate at altitudes in excess of 20,000 feet - Everest is 29,000 feet and has been scaled without oxygen.

The key is acclimatisation, in addition to cardiovascular fitness. Some people seem also to cope with / adapt better to reduced oxygen than others, even with apparently similar levels of fitness. Research is ongoing into possible genetic link to altitude capability.

FBW

mary meagher
2nd Oct 2009, 22:39
Asked to climb to 11,000 feet to avoid a military exercise over the Florida panhandle, I complied.

My passenger was a teenage boy, heavy smoker (!) who had helped me to sail a small boat from Panama City Florida to St. Pete. I had tried before
to discourage his smoking with no effect.....

But when I informed him we would be climbing to an altitude where he might be more affected by a lack of oxygen than myself, and to let me know if his fingernails were turning blue, he spent the rest of the flight furtively examining his nails.....

often wondered if that experience helped him to kick the habit. Probably not.

IO540
3rd Oct 2009, 08:52
It is possible to acclimatise to operating at high altitude without oxygen.

You would have to do an awful lot of flying for that. Many thousands of hours a year, IMHO.

The problem with planes is that even a slow one will reach FL200 in well under an hour. That is a helluva rate compared to climbing some place.

Crash one
3rd Oct 2009, 09:39
Quote:
It is possible to acclimatise to operating at high altitude without oxygen.
You would have to do an awful lot of flying for that. Many thousands of hours a year, IMHO.


One could acclimatise oneself by standing on a big hill for a week or so, don't cost so much.:ugh:

Runaway Gun
3rd Oct 2009, 10:28
It'll take a long time to build a 20,000 ft hill in Scotland too.

englishal
3rd Oct 2009, 10:39
but then he puffed through 40 fags a day.
You have to remember this is an international forum and Americans might be reading this :};)

Runaway Gun
3rd Oct 2009, 16:52
Orally or Aurally?

SNS3Guppy
3rd Oct 2009, 19:14
A spiral dive will always take place pretty fast, in the absence of roll axis input. 1 hr is far too long.

I was once flying my boss in a Cessna 150 from Wichita, Kansas, to western Kansas. Some time after takeoff he suggested I put the airplane on autopilot. I said I didn't know we had one. He reached into the map compartment and withdrew a large, thick rubber band, and snapped it between the control yokes. He then fell asleep, listening to music. I decided to see how long the airplane would hold heading. With it trimmed for pitch, we flew for an hour on heading, with very little altitude excursion.

I've gone for very long periods without any aileron or rudder input, without difficulty.

What occurred with this flight is not known. Guessing will not change that.

IO540
3rd Oct 2009, 19:22
What occurred with this flight is not known. Guessing will not change that.

Well you know what the most wonderful thing is about aviation? One learns something every day

:ugh:

Runaway Gun
3rd Oct 2009, 19:33
And I thought I flew with some idiotic pilots !!!