@ vapilot2004
......the difference between the HUD depiction and the PAPI visual depiction?......If true, the ILS (facility & aircraft) should have been checked after the accident. I wouldn't mind reading more on that.
Depends on which part of the HUD display the captain was focusing on, the ILS loc/gs bars, or the velocity vector (aka "bird"). Although they are in close proximity (one hopes).
The LGA RWY4 ILS approach plate has a note saying "VGSI and ILS glidepath not coincident". Following the VGSI, the TCH is 22 feet higher than the TCH for the ILS. (76 feet vs. 54 feet).
If the captain was watching the HUD's ILS crosshairs, and the FO was flying the PAPI, the captain would indeed have seen the aircraft high on GS -
even if it was correctly tracking the VGSI glide path. Not something that needs to be "checked" - it already has been checked and documented - a "normal" and known discrepancy for this approach.
(As to why the discrepancy is allowed, you'd have to take that up with the FAA or PANYNJ).
If, as misd-agin mentions, she was watching the HUD "bird", that might have been giving yet a different picture, since it pays no attention to ILS or VGSI, and simply calculates where (at current descent rate, drift and speed) you WILL meet the runway.