Kestrel DG200 canopy mod.

On Thursday, June 11, 2009 at 2:45:37 AM UTC-4, Bruce wrote:
OK

Anyone out there with experience in converting the T59D / 401 Kestrel
canopy from the awful removable thing with a hoop exactly where you want
to watch the tug, to a single piece.

Apparently there is an approved mod using a DG200 canopy.

Second question is - would there be anyone with such a canopy /frame
assembly for sale. As I understand it you need the entire DG hinge and
pedestal part too.

FWIW - I am considering modifying a Mark 2 Slingsby T59D Kestrel 19m -
though to the best of my knowledge the canopy and cockpit is identical
on the various Kestrels.

Any advice gladly received.

Cheers
Bruce

Further to my earlier comments on desirable mods., I just remembered an important one.
As received new from the factory, 1972, I discovered that despite the vne
of 145 kts ( from memory); at sowewhere around 90 kts, a kick on the pedals would instigate rudder flutter, quite disturbing but killed by pressure
on both pedals.
AS in yugoslavia in 1972 , we never got to fly near Vb, let alone vne,
this was not a concern.
However, when I was repairing this glider 4 years later, I discovered
a reason for this flutter.
Normal composite fuselage construction uses plies at 45 deg to the axis
which yields the maximum torsional stiffness for the laminate.
My fuselage as laid up by the gnomes of Kirbymoorside, had plies running
parallel to the axis, ie 1.4 x less torsionaly less stiff.
(the first rudder flutter mode is torsional)
Moreover, the mass balance on the rudder was at the bottom , the wrong place
for torsional mass balance; it should be near the top.
Nothing I could do about the layup, but moving and adding to the mass
balance near the top of the rudder moved the flutter propensity
above 110kts, unlikely in a proper final glide.
These faults may have been corrected for later serial #s but I suggest
flutter testing in small increments above 85 kts.
John Firth Ottawa.