Originally Posted by
Tu.114
2. Looking at the quadrant, not only are the flap lever and the condition levers right beside each other. Also, their respective position may well have been quite similar. I obviously stand to be corrected here, but I gathered that the condition levers are normally in "AUTO" in this flight phase - the flap lever was in position 15°, so they were rather adjacent to each other. Additionally, the required travel from 15° to 30° on the flap levers seems rather similar to the travel from AUTO to FTR on the condition levers.
Indeed the position is quite close to each other.
Buuuut:
The haptic differences between two versus one lever and the very different unlatching actions seem to be the only remaining 2 cheese layers that prevent a misselection in a rather high-workload situation in which the often-performed selection may be performed without looking at what lever is being grabbed.
The shape of the levers and the unlatching mechanism are indeed
veeeery different. That is probably why this hasn't happened before (at least not with such consequences that I'm aware of).
The chances that in this case indeed a mix- up did happen appear to be high. Remains pretty puzzling, though. Also that apparently no one checked position of the levers even when after applying power nothing happened. Normally even peripheral vision should have been enough to ring a bell. And all this in bright daylight. And no cacophony of alerts, No direct emergency that would have caused havoc in the cockpit. Nothing which would explain why it a) happened in the first place and b) wasn't detected afterwards. But from the basic facts we know chances are still very high that exactly this happened.