In 1923, the HP.22/23 motor glider was designed by W.H.Sayers, three were entered for the Lympne light aeroplane competitions of that year.
The first, No.23, was initially powered by a pylon mounted air cooled 397cc ABC flat twin. It failed to fly, even when repowered with a 500 cc Douglas.
Attempted catapult launches by four men pulling a rubber cord also failed and No.23 was scratched from the competition.