Also, if you are going to ignore the RFM and keep trying for land, knowing your gearbox could be on the way out 30 minute run dry or not, would you fly it at 130kts ??? or at 800ft???? a fall from 800ft, with no forward motion is still going to hurt, A LOT. ive spoken with s92 pilots on the matter including one who has survived a tail rotor failure of the s92. he said "30-40ft above the sea, and crawled in!" thats what the cougar guys should have done. i dont want to speak ill of the dead and they did pay with thier lives, but is this or is this not, the reason for the outcome in this case? thats not to say that lessons cant be learned, but lets stay focused.
You have raised my curiosity enough to break lurk mode. I may have an answer for your question.
I realize the S-92 isn't the Seahawk/Blackhawk, but I do recall that if you are trying to make it to the ship and your MGB has chips/secondaries/out of oil, the profile you were given in the NATOPS manual was fifty feet and fifty knots. Granted, that guaranteed nothing. It put you into an envelope where the next symptom of "it all going wrong" allowed you a quick drop-flare-ditch to egress and swim away with your lives.
The discussion here on the risk management challenge the aircrew faced has been sobering.
"Yeah, I can ditch, but will likely freeze to death once I do." Thanks, I'll not sign up for a bowl of that soup, given a choice.
However, if that's how you read the situation, I understand why an aircrew would choose a course of action to avoid a ditch as long as practical, and hedge against possible TR thust loss.
Did the TR drive failure catch them by surprise? Likely. Might have been looking for a failure in the main and had a delayed reaction to the TR drive loss.
But back to the decision to get as close to land as soon as could be done. Something conservative like fifty-fifty gets you there slow. If the crew believes in a 30 min "mulligan" for this hole, it barely gets you where 130kt/800' does in terms of "we will likely freeze to death" as an alternate assessment.
As noted above, when the TR stops doing its work, you auto.
So, to answer your question: why choose 130 kts?
130 knots looks a little like the kind of airspeed we were taught to fly if we had a TR drive failure in a Seahawk (around 125 kts actually), hadn't lost energy/nose into the wind configuration, and were trying to keep the nose streamlined into the wind. (Can't recall if anyone ever successfully pulled that off for long enough to find a place to auto ... memory foggy)
The crew might have been anticipating a lost TR, and thus had the helicopter at an airspeed that would keep the nose from cocking/tucking right, and creating the nightmare "one quarter turn broadside to the wind that commits you to the auto." That quick tuck/massive drag problem got a guy I knew killed in San Diego, TR drive failure, back in '89.
Granted, I freely admit that I am applying a bit of apples and oranges here. I base that estimation on the S-92 being a bit of a Blackhawk/Seahawk on steroids. (yes, a gross estimate.) If any of the S-92 drivers can tell me how close my guess is, in terms of
"Can you keep xxx knots up and prevent the nose from breaking right with te TR losing drive"
I'd appreciate it.
It is very sad to read of mishaps like this, when the choices between the devil and the deep blue sea plays out so tragically for those in peril in the air.
Vaya con Dios, amigos