During the nearly two years that elapsed between AF 447 disappearing and the recovery of the flight data recorders nobody suggested that the PF might have, unwittingly, flown the aircraft, stalled, into the ocean.
AI 171 may prove to also have a totally unpredicted cause.
This was my thinking too. Extending this thinking, the technical aspect is generally quite predictable, the human element not so.
I\x92m absolutely not speculating this is the case here, but could you not achieve the effect this flight suffered by just switching off the fuel control switches at 100ft on takeoff?
There are now so many assumptions based on the assumed state of flap, RAT etc that it\x92s becoming pointless speculation.
Just a thought regarding the possibility of some kind of sensor failure: mud wasps.
Since this was a short stopover, perhaps pitot covers were not used. Mud wasps can build their nests in a very short timespan, and they have been known to block pitot tubes and static pitot ports in the past.
Just throwing this out there as one additional possible hole in one of the slices of cheese.
787 doesn\x92t use an old fashioned system but an ADRS that displays a voted trusted speed (the same speed is displayed to both pilots). Block a pitot and it will vote that data out. Block all pitots and you\x92ll get a NAV AIRSPEED DATA EICAS and the AOA speed will be used as a valid source. You\x92ll only end up in an airspeed unreliable condition on one of three fault scenarios\x85simultaneous blockage of 2 of 3 pitot, complete blockage of 2 of 3 static ports or simultaneous seizure of both AoA vanes. Then the system gives you an EICAS with a memory action involved (disconnect AP, disarm AT, both FD off and set 10degrees up, 85% N1).
I looked for a B787 EFATO memory item in the QRH but could not find one. Perhaps a current B787 pilot could confirm?
I don\x92t really know what you are talking about. I\x92m current 787 and have flown many types including airbus prior to this. EFATO is normally an SOP handling exercise, not a memory item in itself. Memory items on nearly all types cover the specific drill for the engine only in all regimes of flight\x85ie severe damage/separation, engine limit exceedance/surge, engine fire. ie you\x92d never say \x93I\x92ll take the memory items for an engine failure after takeoff\x94.
EFATO handling is similar on most types too\x85in essence, contain any yaw, rotate, get the gear up and either trim it out or (787) let the aircraft trim it out\x85.AP in and once safely climbing away at a defined altitude diagnose followed by memory items if applicable. 787 you don\x92t action any drills until above 400ft so it would be extremely unlikely this crew actually got the stage of touching a fuel control switch.
I am only asking about an engine failure memory item. Fire, separation or severe damage being a different beast.
Are you confirming that there is no specific engine failure memory item? When safe run the QRH?
Eng Fail is not a memory item, it will bring up an ECL and is activated when engine speed is below idle. Problem is, if you get severe damage to an engine, it is likely to display engine fail too. 787 SOP is to carefully diagnose what you see and action the severe damage/separation memory items should you decide it\x92s severe damage (ie airframe vibrations, abnormal indications\x85no rotation etc, or engine separation). Initial diagnosis can happen anytime after getting the AP in at 200ft. Sev damage memory items are delayed until above 400ft once the appropriate lateral and vertical modes are confirmed. If it was just a case of engine failure (ie with no immediate memory actions), you\x92d complete the ECL at acceleration altitude once cleaned up.