PPRuNe Forums - View Single Post - constant speed or variable speed approach
Old 30th Jun 2020, 05:07
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Ascend Charlie
Join Date: Sep 2002
Location: Great South East, tired and retired
Posts: 2,838
I think he is asking about a visual approach to a landing site, rather than an instrument approach.

I always did it at an apparent walking pace over my toes. At 300' it equates to 60kt, having selected the hover attitude. Hover attitude, walking pace over the toes, controlled rate of descent.
As the descent continues, the speed bleeds off.
Around 30kt the power starts to come in, a gradual change to the ah-send of the power curve, holding the attitude steady, not letting the secondary effect of collective kick the nose up. Hold the hover attitude, same walking pace over the toes, and you end up in ground effect at walking pace, about to stop, and knowing that you have the power to terminate.

The problem with a 60kt approach is not knowing if you will fall through at the bottom, either through slow response from the engine, or insufficient power available. The pax might not appreciate the rapid flare upwards, the rapid roll-over to level, the rapid increase in engine noise, and the rapid increase of metal tearing itself to bits around them as you misjudged it.

And anyway, if you are on an ILS, your autopilot should be slowly reducing your speed from 120kt to 70kt without you having to activate a brain cell.
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