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wakpilot
4th Dec 2004, 14:23
My first post after 2 years of reading..first..i’m a wannabe..hence the dumb question..
I’ve recently been to the US and saw on TV (discovery channel) a clip of a 707 doing a barrel roll in Seattel..(I’ve subsequently read Boeing’s history where is a very amusing few paragraphs…)..I also recall reading here that a large asian carrier rolled a a340 over India (although I cant seem to find the link..so if anyone has it please let me know)..my question is..if I recall from the old link, the rudder trim had been run full out and the aileron put in opposite correction..the Captain when he came back after crew rest turned off the auto pilot and the aircraft rolled; BUT..how could it do that at altitude, that’s why there is an auto pilot bank limit?..it should have stalled..? (right) and even though is a positive G maneuver.. how come no one noticed?.. my question therefore is..did this happen, how is it aerodynamically possible..given the altitude…It’s obviously possible, but probable at altitude??

swh
4th Dec 2004, 14:58
large asian carrier rolled a a340 over India

Not an A340..will not let you do it unless you turn a number of computers off...sure your not talking about the747 inflight upset (http://www.rvs.uni-bielefeld.de/publications/Incidents/DOCS/ComAndRep/ChinaAir/AAR8603.html) ?

:rolleyes:

wakpilot
4th Dec 2004, 15:47
many thanks for this..but i do recall that there was an airbus roll over india..in this situation..given the CA flight was at fl41, did it stall first?...

SR71
5th Dec 2004, 15:38
wakpilot,

Not sure about the A340, but it is quite possible to barrel-roll a 737.

Done it a number of times in the sim.

:ok:

Genghis the Engineer
5th Dec 2004, 16:16
Never assume that a sim is correct at or outside the corners of the envelope - it's only extrapolating from the available flight test data, probably wrongly.

G

John Farley
5th Dec 2004, 17:14
Genghis

Amen to that

Good luck Tuesday

John

SR71
5th Dec 2004, 17:29
Quite happy not to do that gentlemen although the comment was slightly tongue-in-cheek.

Thinking about it a little more, then, the relevant aerodynamic variables with respect to a barrel-roll shouldn't come anywhere near the edges of the envelope during this manoeuvre though, should they?

And even if we aren't, the aerodynamics isn't sensitive to \phi!

A dangerous assumption, perhaps, but if a 707 can do it, a 737 probably can. The aerodynamics isn't going to be fundamentally different:

Tex Johnston Print (http://www.707sim.com/texjohnston.html)

:ok:

fire wall
5th Dec 2004, 20:41
I believe the a/c concerned was a A310 from the national airline of the land of "lah"
Then there was the story about one of their 744's doing something similiar, and the one about the 340 where, in an attempt to balance fuel the FO (obviously straight out of the airline trng college in Adelaide) turned off the hydraulics.......which I understand are now a guarded switch whence prior they were not (as I have never flown a bus perhaps someone could elaborate how this can be done get into their subsequent"pickle")
For those lost geographically, the "Land of LAH" sits on the equator and used to be run by the former "minister for everything"..........very unsavoury place

visibility3miles
5th Dec 2004, 21:16
Wasn't some of this discussed already?

http://www.pprune.org/forums/showthread.php?s=&threadid=153776&highlight=cessna+roll

And what is your definition of "altitude"?

http://www.cbsnews.com/stories/2004/11/05/60minutes/main654028.shtml

:D

SpaceShipOne rolled 29 times before Melvill regained control. The remainder of the flight was without incident, and the landing, flawless.

Mr Pitts
6th Dec 2004, 22:41
you can roll about anything if you do it right. I know airbus have banklimiters to 60 degrees but I also know there is a dvd that one can buy with an instructor rolling an A320 in a full motion sim at sas flight academy.

lomapaseo
7th Dec 2004, 02:30
Somebody please explain to me what is the difference between this thread and this one presently active in the Questions forum

http://www.pprune.org/forums/showthread.php?s=&threadid=154666

hotprop
7th Dec 2004, 21:08
In the Airbus just reboot windows in fail safe mode and you can perform any maneuver :E

... sorry, couldn't help myself ...

Jr. Airman
11th Dec 2004, 10:01
In response to fire wall's quotes.... the A340 which suffered the unfortunate roll over Australia was triggered by the CAPTAIN who turned off the hydraulics instead of the fuel pumps while attempting to balance the fuel... a portugese chap if i recall correctly.