There are a lot of issue going on whether the spoilers were extended or not. Some detailed info from FCOM would help you all, in my opinion.
1) The reversers were deployed. (As we all agree)
This means that :
- Engine FADEC was operating.
- at least one LGCIU send the aircraft on ground signal
- TLA to reverse was sent by PRIM
- switch reverse signal from EIU
FADEC = Full Authority Digital Engine Control System
LGCIU = Landing Gear Control Interface Unit
TLA = Thrust Lever Angle
PRIM = Flight Control Primary Computer
EIU = Engine Interface Unit
2) The spoilers were not extended :
Ok firends let us consider that (like some of you not me !) the crew did not arm the ground spoilers then :
Full Extension:
The ground spoilers on the 340 (and 320/330) fully extend during rejected take off (at speeds greater then 72knots) or at landing when both main landing gears have touched down and :
- All thrust levers are set to idle, provided ground spoilers are armed
or
- reverse is selected on at least two symmetrical engines (remaining engines at idle)
Patial Extension:
The ground spoilers parially extend when reverse is selected on at least two symmetric engines (remaining engines at idle) and one main landing gear is compressed. This partial extension, by decreasing lift, will ease the compression of the second main landing gear and consequently will lead to the normal ground spoiler extension.
Ok so as the reversers were open at least one LGCIU felt the landing and according to the spoiler logic they must have been extended although they are not armed but here it comes :
On the introduction of the spoilers the book says :
The system automatically retracts the spoilers to their zero position, if it detects a fault or loses electrical control
So let us wait the end of the investigation and please not try to argue the crew.
Safe Landings to all
