PDA

View Full Version : Lufthansa A321 pushback incident


LEM
21st Oct 2004, 19:08
Paxing today in EDDF I saw a LH A321 D-AISG pushing from gate A30 at 15:30 utc...

I was thinking "*****, these guys push fast like crazy" when SUDDENLY the airplane came to an ABRUPT STOP, with the bar almost at 90 degrees to the left.

That was a hell of a stop! FA must have all fallen down.

I wonder what happened. Did they set the parking brake by mistake?

After 10 minutes with a half dozen people investigating, the same truck pulled the airplane back onto the stand.

Flap Sup
21st Oct 2004, 19:29
LEM,

most probably it was just a sheerbolt in the towbar that broke. Happens all the time. If the AC was pulled back to the stand after only 10 mins, you can be sure that nothing happened to the gear.
Btw, sheerbolts are there to break.....

/fs

LEM
21st Oct 2004, 22:25
:hmm: Hmmm...
Sounds quite strange...

Why should the shearbolt have broken? The same truck towed the airplane back with the same bar.

The airplane was severely shaken, as if they had suddenly set the parking brake.

If nothing happened to the gear, why didn't they change bar to continue the pushback and depart on time?

52049er
22nd Oct 2004, 08:40
Most likely that the problem was with the tug. If they get an 'oversteer' warning (happens occasionally esp if it is wet) the safety devices on board the tug apply the brakes pretty abruptly. Last time it happened to me they had to send a techie out to reset the tug before it could drive off.

jaja
22nd Oct 2004, 09:07
I have experienced the same thing, when I was a FO.

During pushback the captain selected the ENGINE MASTER SW. to START ( cw turn), or at least he would like to do that ! Instead he did the same cw movement on the park brake handle, which made the a/c stop very quickly.....

LEM
22nd Oct 2004, 14:58
52049er, so why pulling the aircraft back to the stand?
And with the same tug?

jaja, there was a thread on Techlog some time ago about the risk you are mentioning, on the Bus.

My bet is the captain rotated the wrong handle...:E also because that happened exactly at the point I expected them to start the right engine.

Can't happen on our jurassic jets...;)

autoflight
22nd Oct 2004, 21:07
Tug disconnect during pushback has potential to be more serious. Need for brake application during fast push down slope with rear c of g could see premature "rotate".

Sky_Captain
22nd Oct 2004, 22:11
If the parking brake had been set during push, its likely the sheer pin would have sheered and the tug would not have been able to tow it back to stand without a new bar.

I had a tug stop after the push back and suffer a hydraulic problem. Couldn't disconnect the tug from the bar, which is the sensible thing to do first. It was an Airbus 321, and unless the tug disconnected first, ground crew were unable to disconnect the bar from the nose wheel. After 10 minutes on the taxiway we were instructed to be towed back on to stand to fix the problem there as we were causing an obstruction:confused:

LEM
23rd Oct 2004, 08:36
If the parking brake had been set during push, its likely the sheer pin would have sheered and the tug would not have been able to tow it back to stand without a new bar.
Agree, when they are pushing the airplane straight rearwards, but in this particular case they were just turning the airplane, with the bar almost at 90 degrees to the fuselage, so maybe the pin didn't sheer despite the violent stop. The airplane was shaken above all laterally.

Btw, just speculating...
Must have been really embarrassing for the Captain :O :O

HotDog
23rd Oct 2004, 09:14
Why should the shearbolt have broken? The same truck towed the airplane back with the same bar.

Probably just fitted the spare shearpin which takes 5-10 minutes.

Safety Guy
23rd Oct 2004, 12:08
It could also be that the nose wheel 95° steering limit on the A321 was exceeded, and that they pulled it back onto the gate so that maintenance could perform a proper inspection.