Rescue 116 Crash at Blackrock, Co Mayo(Mod note in post 1)

TomOnBoard wrote: »

Have a look at post #1460 from IrishSteve that refers to Jurgen White saying there would be nothing unusual in such a manoeuvre. However, that was clearly based on it being at some height lower than 4000 as it had started its descent (as radioed to controller) but nothing like the subsequently reported altitude at Blackrock.

cosanostra wrote: »

Listening to ATC archives at approx 0035

Rescue 116 "passing 4000ft now in the descent making our way into Blacksod for refueling"

This was roughly 10mins before they reached blackrock

Irish Steve wrote: »

To clarify the descent process, based on comments I have both seen and read elsewhere, and on operational practice, the cloud break procedure is effectively an ILS style approach, using a similar descent profile to an ILS, which from around 3000 Ft would need something close to 8 miles to perform. As I understand it, they normally use a final descent point that is at least 2 miles from the coast, to ensure clearance from terrain, so in many respect, the ideal area for that procedure would be to go outbound to Blackrock, then fly a procedure turn, which can be in any direction, but usually offset from the outbound course by 45 degrees, and then I would have expected them to descend to 3000 ft after completing the turn, with Blackrock being the point where they would turn inbound and start the descent towards Blacksod, while it's not aiming for a landing point in the same way, it's pretty much identical in terms of profile and distances to a standard instrument approach to a runway for landing, so the "feel" of the aircraft in terms of speeds and descent rates would have been pretty much the same as they were used to using on a regular basis when returning to base for landing, or when looking to make contact with a vessel on the surface. They were also trying to make radio contact with the other aircraft, so going outbound and then to the North West would have given then the best chance to be able to receive a signal from the other craft involved, and at around 4000 Ft, they should still have had contact with Shannon. Operationally, there's nothing about their plan that looks even slightly unusual, and it would not have been the first time they would have used that procedure or one very similar to it to get into Blacksod for fuel.

They would not have flown a direct track from Blackrock towards Blacksod, as that would have meant going closer to land masses that could represent a hazard, the inbound track being the reciprocal of the outbound track is clear of obstacles at the later stages, with the final approach then being to turn towards Blacksod once clear of cloud and with positive visual contact with the sea and/or land, and probably with Blacksod lighthouse as well for confirmation.

And yes, in passing, that suggests to me that Blackrock was in their database, and they were using it as a confirmation of their position in relation to the task, their prime principal would be exactly the same as in any other IFR flying, (fixed wing or rotary wing) never depend on one navigation aid or system for confirmation of position, always have a second system or process that confirms you are where you intend to be.