Originally Posted by
DHfan
It was the Hummingbird that finally convinced Geoffrey de Havilland that motorcycle engines or similar were never going to be any good to power a practical light aircraft.
Off he went to Frank Halford with the idea for the Cirrus.
I owned a Monnet Moni in 1986; 30 bhp 2 stroke similar to the Hummingbird (don't know what the 'RAC' HP rating was) and cruised at about 90mph so it can be done. I remember someone flying the Hummingbird at Farnbrough in (I think) 1970; I was there as a spectator 4 years before I was posted in there. It only managed a straight flight then landed at the far end of the runway!
Second thoughts, maybe that was the EE Wren I'm thinking of.