Hi Martin,
Originally Posted by MartinM
The AP disconnected automatically, but what happened before? What actually made the AP disconnect.
AP, ATHR, flags on PFD, etc. all disconnected at 0210:05 due to unreliable airspeed processed by the PRIMs (Flight control computers)... this is the root cause of everything. The system switched to ALTERNATE LAW (PROT LOST) at this point because two or three pitots displayed a variation of airspeed above 30 Kt during one second. As this event lasted more than 10 seconds, ALTERNATE LAW would be definitive until the end of the flight, but autopilot and autothrust could have been re-engaged later if two calculated airspeed would be considered valid again by the PRIMs.
There is absolutely zero doubt that this is why AP went off.
Originally Posted by MartinM
I plotted the position of the wreck and the position where the Tail was found. The Tail actually was found 70Km northeast of the location of the wreck. While the sea current where at that day were going northeast to south. How the heck did the Tail get so far away from the wreck assuming that it was still sitting on the tailcone on impact.
Do you remember also that the floating wreckage was found drifting 6 days later?
The "Tail" was not found: it was the vertical stabilizer part of it... This piece wasn't drifting alone but with the main floating wreckage, including something like 3,000 pieces of this aircraft and 50 bodies.
Originally Posted by MartinM
Bringing these two elements together makes me assume that the tail was already ripped of the plane earlier. While in deepstall? No. But at what point in time. Maybe exactly at the point when the pilots were doing a right turn. Remember, the FDR said, pilot gave stick input to the left and up. At the same time, ACARS reports a failure of the RTLU. Well, I would say, tail gone, RTLU gone. Logical response of ACARS to report it as failed
As BAE has not release exact coordinates of the flightpath, it makes it hard to overlay with the other position. fact is, they turned back before the decent and due to this the theory looks valid to me.
Opinions?
Come-on!
RTL (rudder travel limiter) fault is related to RTL airspeed function that was invalid due to PRIMs rejection! (you can't set a value limiting RTL deflection without a valid airspeed)... NOT that it was ripped off!!! There was 36 cases discussed in BEA reports about "unreliable airspeed" and each had the same RTL fault. All this aircraft landed with their vertical stabilizer!!! This fault could be cleared once the airspeed will stabilise and be considered valid again by the PRIMs.
Please, go read the BEA previous interim reports; they won't write again everything that was already validated as "facts" in each subsequent publication (like this last note). They will only write about any new findings that could invalidate/correct anything previously established (and so far, nothing appears contradictory to what was already established).