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The early 1960s will always be remembered
for the Standard Austria and Foka series of Standard Class gliders. These
set new standards in designs paving the way for the glass-fibre era which
came shortly afterwards. I will always remember sitting in the SHK and
lying in the Foka for the first time and comparing their slim fuselages
to the ungainly Skylarks and Olympias we were familiar with.
The Standard Austria was an immediate success and production was taken
over by Schempp-Hirth. Perhaps for British conditions it was a little
fast in circling flight and by 1965 the first SHK with 17m span came to
the 1965 World Championships at South Cerney in England to take 3rd place
in the Open Class flown by Rolf Kuntz of Germany. At the same Championships
the Fokas from Poland came 1st and 4th in the Standard Class.
All round, the SHK must be the finest of all the wooden gliders produced.
Developed from the Austria, the wings for the SHK had been redesigned
to 17m by the Akaflieg Darmstadt, the V-tail greatly enlarged, and the
fuselage lengthened, in addition to increasing the cockpit size to cater
for larger pilots. Whereas the earlier machines had been designed for
the Standard Class which in those days had to have fixed undercarriages,
being Open Class the SHK could be and was fitted with a retractable main
wheel and no skid.
There has been much discussion about using V-tails. Many of the earlier
gliders with them did not allow for the fact that for satisfactory stability
and control, the tail surfaces needed to be much the same area as the
combination of a fin, rudder and stabiliser. The result of lacking area
was poor ground control and low stability. However, the SHK got it about
right and the handling and control is excellent for its day.
I look back with amazement at how long it took us to adopt trestles for
rigging and de-rigging and how with a new glider we would struggle with
the rigging.
I took care not to go near when the SHK was being rigged until the syndicate
who had one had learned the tricks to rigging it. It was a real struggle
without trestles! Nowadays the rigging seems simple. It just goes together
like any other sailplane. The wing root is heavy because of the massive
wood main spar but the tails are simple and just slide on to the two spigots.
The rudder causes a very slight pitching
The V-tail is all moving with anti balance tabs to provide both trimming
and feel. They each have an external mass balance mounted forward at the
tips of the tails. The fact that it is different to a normal tail with
a horizontal stabiliser is only just discernible in flight - probably
it is because using the rudder causes a very slight pitching that gives
the game away.
Whether or not a V-tail is really a lower drag than a normal one is debatable.
There are only two tips to develop tip losses and two roots to cause interference
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