Originally Posted by
HeliComparator
I think it was addressed. Firstly the (false) expectation that there would be a much longer period between engine flameouts, and secondly that when 500’ agl over a city at night without a radalt or landing light, a successful autorotative landing is highly unlikely in reality. Which is true.
If you would like to demonstrate that you have made a successful engine off landing in a built up area from 500’ at night etc, then I might be persuaded otherwise but failing that, I’m with the sheriff. Those who think they could do it have never tried it..
HeliComparator. I'm not saying that I would perform any better or worse in the circumstances as presented. I've certainly never done an EOL at night from low level over a city in an EC135 - but then I'm guessing no one else other than David Traill have either. Not having done it personally, does not preclude intellectual debate as to what might have happened.
My observations from the AAIB report are that the aircraft crashed with zero ground speed and zero rotor RPM. That's quite an achievement from 500(approx) feet agl and about 100kts groundspeed. If the pilot did nothing at all, the aircraft trajectory would still have some forward element would it not?
The report stated that the Low NR warning activated twice, was extinguished twice and then activated a third time and remained on. My hypothesis is that the first warning activated shortly after the second engine failed. The pilots instinctive reaction would be to lower the lever. If there was a restriction and the lever couldn't be lowered fully, only partially, a cyclic flare could recover the NR. This could potentially be achieved a second time but once forward airspeed and hence flare effect is depleted there's no further way to recover NR. This scenario could explain the rotor stall and the lack of ground speed.
Could something as simple as a clipboard or tasking folder have been in exactly the wrong place at the wrong time? I find this more plausible than a pilot of his experience, with heightened awareness after the first engine failure, simply mishandling the autorotation (albeit in exceptionally demanding circumstances).
JJ