What happens if you go above the certified altitude?

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JasonM

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Leaving out the "hypoxia risks" in the flight levels..

Say my airplane is certified to FL250. What if I went up to FL300? FL350? What would happen?

I would guess it would start lacking in climb and cruise performance, but would anything catastrophic happen? Would ATC deny the request?
 
Your turbo will be maxed out at that altitude, and the engine will eventually start misfiring because the mixture is no longer combustible and/or the spark gap is too wide for the rarified air.

You can get plenty of climb performance in a mountain wave.

People occasionally soar into the stratosphere (and certainly into Class A), and a glider's absolute ceiling is 0 AGL.

Requirements are an instrument rating, two way radio, transponder, and a clearance, or else prior arrangement, just like any other Class A flight.
 
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MAKG1 said:
Your turbo will be maxed out at that altitude, and the engine will eventually start misfiring because the mixture is no longer combustible and/or the spark gap is too wide for the rarified air..
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But, would that happen at FL260 or FL300? I would have to guess there is some wiggle room there.

What got me thinking about this was say I was up at FL250 and thought I would be clear of the weather, but wasn't and FL300 would have me in the clear.
 
JasonM said:
Leaving out the "hypoxia risks" in the flight levels..

Say my airplane is certified to FL250. What if I went up to FL300? FL350? What would happen?

I would guess it would start lacking in climb and cruise performance, but would anything catastrophic happen? Would ATC deny the request?
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If your referring to the aircraft's ceiling, other than a reduction in climb rate, nothing bad will happen. If you're referring to max operating altitude, then you've exceeded a limitation in the operators / flight manual. I suppose something bad could happen in that case.

Other than traffic purposes, I see no reason for ATC to deny your request. They don't know what's in your flight manual as a limitation or a ceiling.
 
JasonM said:
But, would that happen at FL260 or FL300? I would have to guess there is some wiggle room there.

What got me thinking about this was say I was up at FL250 and thought I would be clear of the weather, but wasn't and FL300 would have me in the clear.
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Now you're a test pilot. I wouldn't want to do that while trying to avoid weather.
 
careful.....if you go far enough....you could end up going orbital to the moon. :D
 
MAKG1 said:
Now you're a test pilot. I wouldn't want to do that while trying to avoid weather.
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Cool! At least I could say I was a test pilot once in my life. :D This is nothing I will be doing, just curious..
 
Velocity173 said:
If your referring to the aircraft's ceiling, other than a reduction in climb rate, nothing bad will happen. If you're referring to max operating altitude, then you've exceeded a limitation in the operators / flight manual. I suppose something bad could happen in that case.

Other than traffic purposes, I see no reason for ATC to deny your request. They don't know what's in your flight manual as a limitation or a ceiling.
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I don't think I have seen two different Altitudes (ceiling/max op) in the POH. I'll have to look again.
 
Thinking about how drastic the oxygen/hypoxia/alertness chart drops off above 18K, I have to assume the aircraft performance drops of very sharp as well above its rated altitude.
 
JasonM said:
Thinking about how drastic the oxygen/hypoxia/alertness chart drops off above 18K, I have to assume the aircraft performance drops of very sharp as well above its rated altitude.
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Depends on the aircraft and it's modifications. The critical altitude on the 'kota has been increased to 18,000, the mags have been pressurized, and fine wire plugs installed. What I don't know and don't know how to test is what the fuel controller will do above it's certified ceiling.
 
LDJones said:
I thought the wings fell off. :dunno:
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That's not until after you leave the atmosphere. It happens like this to help transition to space travel mode.

rocket_srb_separation_edit.jpg
 
Aircraft certification is revoked and the aircraft is recalled to the manufacturer via teleporter. You plummet to earth, only to be saved from instant death by a dude in a balloon lifted lawnchair.
 
JasonM said:
Leaving out the "hypoxia risks" in the flight levels..

Say my airplane is certified to FL250. What if I went up to FL300? FL350? What would happen?
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Wings fall off.

And if you land, FAA police will be right there to arrest you.
 
gkainz said:
Aircraft certification is revoked and the aircraft is recalled to the manufacturer via teleporter. You plummet to earth, only to be saved from instant death by a dude in a balloon lifted lawnchair.
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C-mon!! a lawn chair? really?? I don't believe that. :mad:

You do bring up a good point though.. I wonder if since you would be IFR and be on offical record of doing this; if someone alerted the FAA, if they could take serious action against you or the aircraft if they found out.

Like, say if there was proof someone exceeded the g-limit, and was required to tear down the aircraft for inspection or something? Would that be similar?? :dunno:
 
Aircraft with certified ceilings of FL250, are not limited by aircraft performance.

They are limited by the oxygen systems installed.
 
JasonM said:
Leaving out the "hypoxia risks" in the flight levels..

Say my airplane is certified to FL250. What if I went up to FL300? FL350? What would happen?
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Depends on whether you filed a flight plan.

Rich
 
You'd run into RVSM issues at FL280. I'm believe the mooney M20K has a max operating altitude of FL280.

God help you if you have an O2 failure up there though!
 
Don't forget about the coffin corner...
 
Give it a try,let us know how it works out. Test pilot.
 
frfly172 said:
Give it a try,let us know how it works out. Test pilot.
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Just got back actually. I filed for FL250 so I wouldn't get in trouble on paper, then asked ATC for a block from FL250 to FL600. I climbed pretty good up to FL550 where I could tell the wings were about to break off. There is actually an annuciator on the G1000 at FL550 that says, "Parachute no longer usable. Space travel mode activating in 5..4..3.." I could feel the suction towards the moon and didn't want to see what would happen when it counted down to 1, so I immediately nosed over hard and did a full-on dive back to FL250. I overspeed the aircraft a little to 580 KIAS and pulled 30G's loosing speed before breaking the minimum of FL250. took it easy from there on down. Atleast we know how capable these cirrus SR22's are though.. After 6PC's video of him flying like a fighter pilot down low, I had to see how good it was up high. ;)
 
dans2992 said:
You'd run into RVSM issues at FL280. I'm believe the mooney M20K has a max operating altitude of FL280.

God help you if you have an O2 failure up there though!
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Remember RVSM didn't always exist. Plenty of planes without RVSM (certified in pre-RVSM days) have service ceilings up into RVSM airspace.

These planes can also be outfitted to be RVSM compliant and then use these altitudes. For example, I've seen a few Commanders and Conquests with RVSM.
 
JasonM said:
C-mon!! a lawn chair? really?? I don't believe that.
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Yup, it's true. This guy. Helped him launch one day from KTTA, he only caught three guys on that trip. And before you say it isn't a lawn chair, it's clear that once he lands it on the grass, it is in fact a chair on the lawn.

http://www.clusterballoon.com/

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JasonM said:
You cant land when the wings fall off. We already went over this. You are Moon bound 100%. No return to earth. :nono:
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Unless it's a Duke. Then the tail will have fallen off long before that.
 
LDJones said:
I thought it was the Cough'n Corner....a respiratory thing? :dunno:
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At high altitude stall speed can increase to meet max Mach. As the speeds converge it can give a very narrow speed range which to fly. That's the "corner".
 
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