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Old January 5th 11, 02:11 PM posted to rec.aviation.soaring
Doug Greenwell
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Posts: 67
Default poor lateral control on a slow tow?

At 13:09 05 January 2011, Martin Gregorie wrote:
On Wed, 05 Jan 2011 09:04:12 +0000, Doug Greenwell wrote:

At 02:48 05 January 2011, bildan wrote:
On Jan 4, 7:13=A0pm, AGL wrote:

Has anyone tried some flaps in an integrated flap machine (which
reduces stall speed) to see if the wallowing goes away?

With every flapped glider I've flown, negative flap improves aileron
response fairly dramatically. Positive flap does lower the stall

speed
a little.

I've flown a 20 meter Nimbus 2C ballasted to 11 lbs/sq ft wing

loading
behind a tug pilot accustomed to towing 2-33's. The speed was low
enough to need +1 flap but it didn't wallow. The tug pilot turned

off
his radio when he got tired of me yelling for more speed than what he
"knew" was right.



Sorry if this is an obvious question (never flown a flapped glider),

but
with an integrated flap system what is the relative movement of the
ailerons and flaps? Presumably the ailerons don't move at all for
negative settings?

On an ASW-20 flaps and ailerons move together so the trailing edge
remains straight with the stick central in the flying flap settings: +8
(thermal) through -9 (max negative flap). When stick is moved laterally


the flap deflects half as far as the aileron. In landing flap settings
the ailerons mover to -8 degrees - what the RC glider guys call 'crow
mode'. This reduces tip stalling tendencies and the handbook says this
also increases drag.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |


Ok - so that would help in reducing stall speed slightly, but would not
help with the spanwise lift distribution.

Is the aileron/flap interconnect a standard arrangement, or are there
flapped gliders without it?