COMBAT AND COMPETITION.pdf - Lakes Gliding Club

COMBAT AND COMPETITION
including Slingsby, whose projects suffered as a result. Thickening the
tips would allow the geometric twist to be reduced without adverse
effect on the stall. At high speeds the download on the outer sections
would be
correspondingly less, with benefits to structural weight, and the gliding
angle would be further enhanced. Harry worked out the aerodynamics
of a laminar flow wing for the Olympia. The performance was
dramatically better. So the team decided to build a pair of wings for
the ETPS Olympia.
There were other advantages. Because the wing was thick, and the
maximum depth further aft, the D box 2 was larger and stiffer in
torsion and bending than on previous sailplanes. So the new Frise
ailerons with their reduced trailing edge angle, another feature of the
laminar sections, could be made smaller. The control loads would be
lighter and the response much better, particularly at speeds approaching
Vne.
As the ETPS Olympia still belonged to Elliotts, John Sowrey rang
Horace Buckingham to make sure that he had no objection. Horace went
one better and offered to build the wings himself. The team decided to
carry out full scale tests and Elliotts made up an aerofoil sleeve to their
design. This was fitted to a Kite II and flown with a pilot rake 3 to
measure the drag. China clay and paraffin were used for boundary
layer and transition studies which included the effect of artificial flies.
The results were almost exactly as predicted.
After that it would be pleasant to report that all went smoothly until
the first flight. Not so. Elliotts started on the new wings. Then they
stopped work completely for two years. A strong suspicion remains that
people with vested interests in other projects were rocking the boat.
Whatever the reason Horace simply refused to move until Dick
Johnson's laminar wing RJ5 had flown successfully in the United
States.
The Olympia IV made its first flight at Lasham, where Bill
Bedford, assisted by John Sowrey, carried out the tests for its special
category certificate of airworthiness. When they were finished Harry
took the aircraft up for a brief performance run against Philip Wills in
his Sky. Philip was visibly impressed that there seemed to be so little
difference between his World Championship winning 18 metre sailplane
and the 15 metre Olympia IV.
"As like as two peas in a pod" - he remarked thoughtfully.
After the 1954 World Championships the Olympia IV was returned
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