Blackhawk-CappyJax
Re Post 13:
The UH-60 ( or any of our other machines ) is not in VRS at 26kts/-1700FPM.
The n/rev roughness that may be felt at speeds/rates of descent in that area is the result of one advancing blade intercepting the tip vortex from the preceding blade.
In fact, if one looks at the standard flight test card at SA for a flight loads survey test flight, one will see a maneuver called a Rough Approach and this is how it is flown. Now, the numbers, I.e., airspeed and ROD can vary depending on the GW and CG ( remember, it's the intersection of the vortex that trips the n/rev vibration ) but it is findable on everything from the S-58 to the S-92. Note:This flight condition does not result in any of the sharp peaked pitch and roll attitude excursions symptomatic of VRS.