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Old 9th May 2023, 16:02
  #35 (permalink)  
fdr
 
Join Date: Jun 2001
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Originally Posted by SLFMS
Oh God here we go. VRS or not, settling with power, Vuilchard. Where’s the guy that hates twins…..

Let’s settle an easier topic like a peace process for Ukraine.

Guys always focus on ROD for VRS, whereas it’s actually flow though the disk. A big flare downwind, to the disk is the same as ROD.
My two cents is it looks exactly like VRS and ticks all the boxes.
Not quite... I understand the sentiment, but a flare with any forward IAS will reduce inflow through the rotor disk. If there is no airspeed, then the consequence is not altering the inflow to the disk, but the angled lift vector will result in higher AOA demand to avoid a descent developing, and that starts getting into the potential rapid entry into over pitching, where the Nr starts to droop due to the excessive AOA related torque demand.

VRS is related to a re-circulatory flow field down through the rotor disk, and that means it isn't encountered in an autorotative state, which is what arises in a big flare downwind. Now, coming out of the flare, there is an increased thrust requirement, a skittish directional stability issue, and a need to still counter the tailwind condition if you are external referenced.

Last edited by fdr; 22nd May 2023 at 01:41.
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