wrote, On 11/11/2013 12:09 PM:
On Monday, November 11, 2013 10:23:46 AM UTC-5, WB wrote:
A prototype automated flap system was mentioned in the recent
Duckhawk discussion. My question: Given that our manual flap
settings cannot be optimal, how much real-world improvement in
climb and cruise could be gained with an automated flap system that
always has the flaps at their optimal position ( a hypothetical
"perfect" flap setter)? --- news://freenews.netfront.net/ -
complaints: ---

Most current flapped gliders are fairly tolerant of errors in flap
setting. The challange with automating flap settings, other than the
relatively simple glide portion of the flight, is that the flap
change quite likely needs to lead the change in lift coefficient. It
also would need to have some serious filtering to take out gust
effects. Add to this a need to not overdo changes to avoid running
the power source down. Sounds like a very complex project with a
marginal benefit, especially when applied to gliders with tolerant
airfoils. Then again, thinking back to my PIK-20, it would have been
useful. I wore myself out keeping the flaps in the optimum position
for the required lift coefficient. Thank goodness for modern
airfoils.

My understanding, based on comments from some of the Duckhawk folk a
year ago, is the flap motion will be fast enough to take advantage of
gusts; ie, it's not just to optimize the flaps for the speed you've
selected during a long glide.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)