Originally Posted by
Rananim
A lot to discuss and no real hard information.It can get confusing and counter-productive.We have the write up by commander of previous flight and the
ADSB data.
UAS comes in all shapes and sizes.Total,partial,intermittent,insidious etc You can fly into icing in the cruise and lose all ASI data(ie zero...ram air blocked but drain holes unblocked)) with AP siren suddenly awakening you out of your slumber.You can be climbing through icing and get a steadily increasing ASI with an overspeed warning.If you pull back you can end up stalling.You can be descending through icing and get a steadily decreasing ASI followed by stick shaker.If you increase speed you can end up overspeeding,overstress the aircraft with loss of control.You can be in the cruise and ASI just freezes and be totally unaware that you have UAS(total pitot blockage ram air + drain holes) You can enter a hail storm,lose the radome and end up with UAS..And then there are the non-icing events....insects,covers left on etc.A whole myriad of possibilities..
I think the Lionair undoubtedly had a UAS,it was either a repeat of the previous flights scenario but this time control was not handed over to the FO,or following maintenance work both static vents were now affected,they had an overspeed and lost control of the aircraft.It would not surprise me if it was done with the AP engaged right after takeoff.
I agree with you on initial part, UAS comes in all phases of the flight, but the rest is highly speculative. We don't know yet who was PF and how things were handled during this short flight. I expect both pilots to be professional enough to follow the procedures. Some ppl on this panel speculate stalling the plane, which might be very possible. Recent report of Turkish private jet shows example of not following books.
However looking at the FR24 info (if correct), they struggled with climb for 13 min or so to end up stalling the plane?? I doubt and if I am allowed to suggest to the authorities, to start looking for tail section of that plane for clues why it dropped from the sky so quick...