Originally Posted by CappyJax
A Blackhawk at gross weight is in the heavy turbulence area of VRS at 26 knots and 1700 FPM, and may still be in the light turbulence regions at speeds as high as 80 knots.
Cappy: are you referring to
airspeeds as high as 80 kts being in the range of VRS?
At 80 knots in a Black Hawk you are well through translational lift, and not too far from L/D max (max fuel conserve airspeed, max power margin, of course DA/GW dependent) and pretty close to optimal autorotation airspeed (DA and GW dependent) with if memory serves a few knots to spare.
Was 80 knots a typo there? Your post confused me for multiple reasons, but that in particular makes no sense to me. What point were you trying to get across? In flight vibration levels, or something else?
(Memory banks are a bit foggy; while we flew most of our maintenance autos at ~80 KIAS, I seem to recall learning that the sweet spot was somewhere between 70 and 75 kts. I am sure Mr Dixson can fine tune that with his experiences in developing that helicopter).