Mark James Boyd wrote:
...
One wonders if the Sparrowhawk would make it as a world class glider.
Certainly it has much in common with the PW-5 and Russia
(light weight, short wings, easy rigging, better polar but
close, fixed gear, no flaps).
...

At least in one country (France, where I live and fly) the Sparrowhawk
would be illegal. According to the french regulation, for a glider
to be considered as ultralight, it should be foot launchable, otherwise
it must be certified, or have an engine, i.e. not be a glider. So
the Sparrowhawk could only be a world-minus-one-country class glider.