Arm out the window,
The speed is not critical for this. What you are doing is applying a rule of thumb that you have worked out previously (or someone else has) to be able to estimate the power required to hover IGE at the DA you are about to land in.
What you want to be able to say to yourself is this:
"This helicopter uses X amount more power to hover IGE in nil wind than it does to fly S&L at my reference speed at 500' above the landing DA." I used BROC as a good reference speed for the reasons previously mentioned.
An example (I've just plucked the numbers out of my head, and notice that 80 Kts is not BROC for the Jetranger):
You have worked out that your Jetranger uses 15% more Torque to hover IGE in nil wind than it does to fly S&L at 80 Kts 500' higher. So you set it up S&L at 80 Kts, 500' above your landing site, and you are using 75% Torque. You then know it will take about 90% to hover IGE. You can then compare that to your maximum power available and determine your margin at the bottom.
If you don't know a rule of thumb, what I am saying in my original post on this is that you can work one out for yourself by experimentation.
Last edited by the coyote; 16th November 2005 at 21:12.