Viscount724 From Switzerland, joined Oct 2006, 29316 posts, RR: 25 Posted (8 years 3 weeks 3 days 15 hours ago) and read 5364 times:
The photo below of an A340-300 appears in an article on EK in last week's Aviation Week magazine.
I'm just curious if anyone can speculate why the thrust reversers are deployed on the inboard engines only. Are they designed to deploy sequentially, first on the inboard and then on the outboard? In that case perhaps the outboard reversers just haven't opened yet since the aircraft has obviously only just touched down.
Or would there be a reason why they would intentionally only deploy the inboard reversers?
FBU 4EVER! From Norway, joined Jan 2001, 998 posts, RR: 7
Reply 4, posted (8 years 3 weeks 3 days 2 hours ago) and read 5263 times:
There is an interlock mechanism between no. 1 and no. 4 thrustlevers to ensure that both outer engines are at idle reverse thrust before reverse thrust can be increased, thus avoiding thrust assymetry. This feature does not exist for the inner engines, and thrust levers can be moved directly to max. reverse thrust. There is no need to lower the nosewheel to the ground for idle reverse but recoommended that the nosewheel is on the ground before increasing reverse thrust beyond idle.
This interlock may be inoperative in open position provided both outboard thrust reversers are considered inoperative.
It may also be inoperative in locked position provided no operation or procedure prdicated on thrust reverser use. Outboard thrust is not available. This according to A340 FCOM MEL.
So I think the plane is dispatched on MEL 78-30-02 with failed interlock mechanism.
Zeke From Hong Kong, joined Dec 2006, 10730 posts, RR: 76
Reply 6, posted (8 years 3 weeks 2 days 12 hours ago) and read 5131 times:
Quoting Fr8mech (Reply 1): More than likely, the #1 reverser in inoperative and on MEL. There is a chance that the #4 may be inoperative and the crew decided to use only the inboards to avoid assymetrical reverse.
Quoting FBU 4EVER! (Reply 4): There is an interlock mechanism between no. 1 and no. 4 thrustlevers to ensure that both outer engines are at idle reverse thrust before reverse thrust can be increased, thus avoiding thrust assymetry.
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