Originally Posted by
Jimmy.
Consulting a graphic (Indicated Torque Required to Hover IGE, 105%NR, AC Off, Wh = 10ft and AI Off) on a RFM, 500ft AD and Aircraft Gross Wheight of 17,000lb and 26,000lb, I found 50%Q and 80%Q, respectively. If the relation is linear, in this helicopter at these conditions, 30%Q correspond to 9,000lbs of thrust, or 1%Q to 300lb.
So, 17,000lb should require 56%Q, and we didn't consider the torque needed to drive the powertrain...
I would think 26K is outside the optimized hover region for the Apache. Quirky things happen there. L/D should be more linear in the central region where hover occurs for most helos.