marcr
Its certainly worth looking at, but to modify the EGPWS you have to have Honeywell on board, something we don't have at present. But I think the primary difficulty is how would the system diffentiate between a normal landing on a ship, semisub etc versus an unintentional landing on the water. In the case of the ETAP event, gear was down, "AVAD" suspended and all set for landing - they just landed a couple of hundred metres short! If the system gave a false warning every time you landed offshore, it would be ignored, switched off etc and add no value.
Theoretically you could for example have all the installations with their deck elevations in a database linked to the FMS/GPS so that it knew what your destination was (assuming you put it in the FMS/GPS as the destination, which I think we all do), then if you descended below deck height +50' more than (say) 50 metres away you would get a warning.
Difficulties:
1) Need to keep the database of semisubs, ships etc right up to date, tricky for moving ships and for FPSOs where the helideck swings around a large area in currents/wind.
2) This system doesn't exist, who is going to mandate or pay for it?
Perhaps more robust SOPs are a better solution? At the moment all 3 N Sea operators follow completely different SOPs and the CAA are powerless to standardise us - all they can do is check compliance with JAR-OPS 3, which of course we all are.
HC