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Old 19th Jan 2012, 21:16
  #60 (permalink)  
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Aucky - probably a point worth noting re downwind approaches - the disc may not care which way it faces once it is established in the hover but it does when you are flaring to reduce the speed to achieve that hover.

On an into wind approach you can flare to reduce the GS if you think your closure rate is too quick - flare effect is the result of a change in inflow angle giving an increase in AoA.

On a downwind approach, especially in the latter stages, the wind is already from behind you so that any flare has negligible effect because the inflow angle change doesn't increase the AoA.

This is the reason that most are taught that the key to a safe downwind approach is to keep the GS under control as a harsh flare at the end will just put the tail closer to the ground without washing off your speed - you will need a handful of collective to increase MR thrust with the vector pointing backwards - another reason for having a sensible power margin.
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