S76A++ Question for Nick....or anybody else.
I fly an S76A++.. .Two questions have been bugging me for a while, can’t seem to get an answer I’m comfortable with.. .. .1. Why 107% Nr for all ops?. .. .2. N1 Over speed limitation. A little explanation for those of you who don’t fly the A++. 2 X Arrial 1s1 engines. The engine over speed protection works like this.. .2 X N2 overspeed probes 1 X N1 overspeed probe per engine. (A) If N2 hits 122%, it shuts down the engine and disables the overspeed in the remaining engine.. .(B) If both N2 probes have failed for whatever reason on an engine, the N1 probe takes over. If the N1 is above 82.3%, it shuts down the engine. (!) . .How and who worked that out?. .If I voluntarily shut an engine down for whatever reason, does that disable the over speed on the remaining engine or is there potential for a double engine failure?. .. .Regards. .. .Av8r