Australian suctioning glider

Hi,

From NASA,the Australian suctioning glider design with swept-
back wing.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19980055126_1998119193.pdf

This was to be the GAD-4, itself a flying scale model for a 72 passenger all wing BLC airliner,
with a cruising speed in the range of 300-400 mph. It was to have utilised the GLAS II aerofoil.
This was specially designed to use suction type BLC, to give laminar flow. and hence low drag,
even though the section had a 31% t/c ratio.
The glider was to have a span of 50', length 33'9", and height 12'.
Loaded weight was to be 3,500 lbs.
Although the GAD-4 was never built, the GLAS II aerofoil was tested in flight. Following a conference
in 1946, it was decided that suction type BLC should be tested in flight. The Australians accepted
the task, and it was decided that a DHA G2 glider, a WWII designed light transport glider, would be
rerbuilt with a GLAS II wing and suction system.
Accordingly, the DHA G2 glider A57-1, the first of six built, was flown unmodified,to gather baseline data,
before being modified with the fitting of the GLAS II wing.
After modification, flight testing revealed several control and aerodynamic problems, eventually traced to
the problem of contamination induced loss of laminar flow.
By the time the flight test program was completed, interest in suction type BLC had waned, and, following
a period in storage, the GLAS II test glider was disposed of.

More information can be found in 'Australia's Wooden Warbirds', Air International, July 1976, pp.22-30.


cheers,
Robin.

Okay, I missed an image off my previous post, I've tried to add it, but the
software won't let me, so I'll have to put it here.
Here's the GLAS II winged DHA G2 in 3-view, with the standard DHA G2
again for comparison.


cheers,
Robin.

Updating this thread with some contemporary images posted on the thread here :-

http://www.secretprojects.co.uk/forum/index.php/topic,3435.msg27363.html#msg27363

The 72-seat Suction Wing Airliner, and the Suction Wing Aerofoil.

cheers,
Robin.

Good observe my dear Robin.