Polar with spoilers extended?

Alastair Harrison wrote:
Dan G wrote:
SNIP
However I still have a question: do you dive and then return to normal
approach speed before rounding out, or round out at the much faster
speed? If the latter, does not the extra float in ground effect negate
the losses from extra drag in the dive, especially with a slippery
glass ship versus a draggy wood and fabric glider (such as one a pilot
might train in)?

snip


I was also taught this technique on a basic instructors course (in a
G103). But I'm always left thinking that it requires a high level of
skill to judge the roundout correctly. Leaving it just a second too
late would result in a rather rapid meeting with the ground. I think
I'd rather take my chances with a side slip.

As Andreas points out, the maneuver we're talking about is performed
"high" at the early part of the final approach. When the glide to the
desired aim point "looks right", the glider is returned to the desired
approach speed (spoilers still fully out). The spoilers are then
retracted to about half way, and the approach is continued as you
normally would.

If you have to maintain the high speed all the way to the flare, you
were too high to use it. A slip might be better if you are "low" when
you decide full spoilers alone aren't enough.

--
Eric Greenwell - Washington State, USA
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