bodory

https://avherald.com/h?article=4a81da6e&opt=0

https://www.lesechos.fr/industrie-se...ta-2082073.php

Summary: F-GLZU, an AF A340 almost missed two of its take-off at BOG recently. She has been withdrawn from service as a precaution measure. AF and BEA are investigating the case.

brunos

What is worrying is that AF took no action after that incident on 11 March. Hence a similar one happened some three weeks later.
And several others happened before according to Les Echos.

San Gottardo

I am probably super-critical when it comes to these kind of things and usually don't buy the apologetic BS that companies and their fans spin out. But on this one I wonder what the appropriate action would have been.

The plane's performance metrics are perfectly OK for operating from BOG. Thousands of flights with the same plane type and even the same plane have been eventless (=BOG is served daily with A340s by Air France since years, that makes it literally thousands). Other airlines operate the same plane type to BOG, and there have been isolated (as in: one or two) incidents of the same type there, too. What are the choices:

• The crew could have insisted taking off in the other direction, which would have meant taking off with headwind rather than tailwind. Not sure ATC would have allowed that as this would upset the entire traffic pattern for this busy airport, both on the ground (AF plane taxiing against the overall flow) and - even more complex - in the air (AF flying straight into the approach path of all the other planes lining to land in the other direction).
• AF to stop using the A340 to BOG. But there is no indication that this particular plane type has an issue at BOG, performance metrics fully OK. And I doubt that using a twin-engine is the better idea, when you have a four engine plane that using that for takeoff from high/hot fields for trans-Atlantic operation is pretty good.
• Take that particular plane out of circulation? Again, on what grounds. If the flying crews or the suveillance systems have noticed abnormal under-performance of the engines, then yes, but that isn't the case. Also, there may be weight differences between this partilar build and its sisters in the fleet, but then AF wouldn't take it out of circulation but simply not roster it to BOG anymore

I think it's great that the BEA and AF look into this, and AF does the only reasonable thing, keep a quad-engine and make it lighter. But other than that, I cannot see what could be done.

brunos

You are a much greater aviation expert than me (actually I know nothing).
But It is a rainy day in Hong Kong and had early dinner with a lovely NZ pinot noir, so I have been perusing aviation websites. Cannot claim that I understood much.

We don't know what happened in this particular incident on 11 March, but it is an extremely close call.

As mentioned above, my personal surprise is that AF did not take any measure right after this serious incident, but waited for a similar one (maybe less serious) on 4 April to take serious measures such as reduction in takeoff weight and check on that specific aircraft. Opening an inquiry is a good thing, but precautionary measures should have been taken immediately. Of course, it could well be that the information is partial and incorrect, but that is what we have to rely on.

Goldorak

The article mentions also LH having had similar problems. Do we know more from that ?

Xandrios

Even when take off is as planned margins are quite slim. Here is a video of the same AF aircraft, at the same airport/runway. I would not expect it to take much to cross the end of the runway at a very low altitude.

bodory

AF A340 are back on the BOG route. They now do a refuelling stop in PTP on the way back to CDG to get a lighter take-off weigh at BOG.

Goldorak

But they never stop the A340 on this route. They are making the PTP stop now every day since end april.