What I do know is that if the engines aren't chopped by the time the Nr gets down to 60%, they will re-engage
Whoa.....that magic number of 60%......now why ever would EC choose that particular number as a trigger to kick the engines back on line?
Were we not told that more than 5% below the Bottom of the Green would be Endex for all helicopters?
Sid.....you might want to carry this discussion over to the Autorotation Thread and compare some notes with Pete or whoever it is that used the 5% concept.
Seems Brother Dixon, ex-SA Test Pilot, mentioned the "60% Range" meaning from 60-70%....I assume as being the critical range.
This bears discussing don't you think? It might be useful over there.