A340 Performance

[avialuver33]

The A340 seems as though it has small engines for such a large aircraft.

Scenario: 90F, max weight, both engines on one side quit just after rotation. Still flyable?

[mutt]

You could just as easily ask the question about any 4 engine airliner, the one that I believe you will have the best chance in is the VC10.


Mutt.

[avialuver33]

Mutt---thanks for the reply---the 1st I've received as a PPRuNe'er. Yes, I know I could have asked the same about any 4-engine airliner. No slight intended to the A-340---it's a beautiful airliner. I just thought that for its size, the thrust rating per engine was low, and wondered how a double engine failure on one side would affect a hot day, max weight take-off. I am not a pilot, so please be patient if my questions seem strange. For us lovers of airliners, this web site, in general, and the questions forum, in particular, well---it's like being a kid in a candy store! Where else could someone who isn't a pilot ask questions of so many pros?

[Rabbit]

avialuver33

I guess your chances depend on what speed you are at when disaster strikes. Below VMC-2 not much hope, above VMC-2 and there is hope. If there happens to be no obstacles that allows you to fly low (preferrably over water) and get into ground effect while dumping fuel then you might have a chance.

I operate the A340 with slightly uprated performance but still its not the most powerful beast in the sky. I must say its one engine inop' performance is quite good, I had personal experience of this in real life a few days age when an eagle took out number 4 engine just after take-off. I wasn't real heavy but I hardly noticed the loss in performance.

Have a nice day

[GlueBall]

From what we've seen at ANC in February, demonstrated performance was quite excellent!

The heavy A340 managed to get airborne in one piece on a 6000' taxiway and to truck on to TPE.
:p

[avialuver33]

Rabbit/Glueball,

Thanks so much for the replies. It is a thrill to read responses from professional pilots.

[BigJETS]

Im not a pilot but Ive seen a couple shallow climbouts with the 340. Perhaps less difficulty -- for sake of less power?

['%MAC']

There is a short video clip (1.62M) at http://www.videolife.info (www.videolife.info) though certainly at light wieght, it appears to have a decent ROC.

[Nano 763]

I don't wish to be in any way rude to the 340 bus drivers, but our busdrivers say that the only reason that that plane takes off, is because of the natural curvature of the Earth.
;) :) :) :)

[criticalmass]

Ability to handle a double asymmmetric on initial climb might be a function of software installed and flight mode selected on flight management computers (or whatever Airbus calls 'em). At least in an a/c as advanced as the A340 you have a fighting chance. The RAAF found some years ago that a double asymmetric in a 707 was a "do not do this except in the simulator" exercise when it lost one in the sea off Sale, Victoria. The a/c rolled over and played dead...took the crew with it. Old a/c, no automation, prohibited manoeuvre in the ops manual but they tried it anyway.

If the A340 is as advanced as the salesmen say it is, then the FMC should recognise the asymmetric condition and take immediate action via trim and control-surface positions to counteract it. If these automated systems are really that good the first thing the pilots should know about the loss of power will be annunciators/spoken alarms/whatever informing them...but then again, the systems are only as good as the version of software installed.

As for ROC under such circumstances, the CFM-56s on the -200 series are somewhat less powerful than those on the later series, so the ability to maintain a specific ROC would depend not only on weight but also on power rating of remaining good donks and which series of A340 is under consideration.

Info from some A340 drivers (on the different series of a/c) would probably nail this one for you but those are my suggestions, strictly as a non-Airbus driver.