Decided to climb above max alt and turns out nothing happened. I though I would be in a zone that would cause a stall.

Interesting... that yellow warning zone on the speed tape should end in a red zone somewhere... Somebody forgot to do something on this plane...

This shouldn't end in a stall. The problem is just that the aircraft's limits are getting smaller and smaller when entering this altitude. When flying in the yellow tape you can't make the same movements of the aircraft than when flying in the normal zone.

So we're finding a bug in an envelope that would never be entered in the real a/c? Interesting.

Look at the max alt in the FMC, you are above it by 200 ft, which means you are too heavy by that amount for that altitude.

Look at the max alt in the FMC, you are above it by 200 ft, which means you are too heavy by that amount for that altitude.

Yes I know and stated this in my original post. I just wanted to find out what would happen. Mark.

Interesting... that yellow warning zone on the speed tape should end in a red zone somewhere... Somebody forgot to do something on this plane...

What? There is a red zone as far as I can tell.

You're in coffin corner... you have a little bit of limit on the stall speed, but at some point you're going to be both stalling and overspeeding. You should have a stickshaker activation, if I'm not mistaken?

You're in coffin corner... you have a little bit of limit on the stall speed, but at some point you're going to be both stalling and overspeeding. You should have a stickshaker activation, if I'm not mistaken?

No, stickshaker activation is upper end lower red band (IIRC), you're far away from that. Anyhow, I seriously doubt this would result in a stall right away. Sure, you're above your FMC max alt, so? I however somehow have the strong feeling FMC max alt is in fact very much unequal to aerodynamic max alt. So he's definately not even close to coffin corner here I'd suppose, he might just be starting to lose his usual margins. Upper end lower amber band still provides at least 1.3G margin to buffet, the upper amber also has a 0.3 to high speed buffet... Plus there might be safetly margins not indicated on the speed tape you might not know of. Just a rough guess though. Climb a couple thousand feet higher (if you can) and see where that gets you.

And "ABOVE MAX CERT ALTITUDE" message.

What? There is a red zone as far as I can tell.

I meant a red zone below the yellow one, not above it :(

Official Service Ceiling of the NG is 41,000 feet. You could probably take it up a lot higher than you are in that screenie as long as you were doing it at 100fpm. It puts more stress on the fuselage to get it up there because of the pressure differential, but the NG can get up there. You could probably glide to Australia at that height LOL. Al

Did you attempt any maneuvering? Thirty degrees of bank might have put you into a stall.

No maneuvering, just continued on my way. Obviously as I burned fuel a very small window opened up. I have since tried it again continuing to climb as high as possible. I even went into the menu and added full weight and fuel. Eventually the aircraft decided it had had enough and started to descend rapidly into a safer zone. Mark.

Official Service Ceiling of the NG is 41,000 feet. You could probably take it up a lot higher than you are in that screenie as long as you were doing it at 100fpm. It puts more stress on the fuselage to get it up there because of the pressure differential, but the NG can get up there. You could probably glide to Australia at that height LOL.

True. The aerodynamic ceiling (and hence the 'corner' we all talk about) is certainly quite a bit higher than that 41K number. It would be more than dumb if Boeing let people fly up any close to that. Service ceiling could be based on aerodynamic safety margins, but also on structural considerations as max ΔP the fuselage will handle.