Alrighty...
We had nine replies with three being correct, although one was privvy to privileged information.
The three correct replies were made by:
Lufbery
Filibert Kraxner
Butz
The answer?
Port Victoria PV7 Grain Kitten
Here's the un-altered image of N539:
The aircraft was constructed by Port Victoria at the Experimental Construction Depot on the Isle of Grain, with N539 being the sole example built. It was developed in response to a requirement for a small, lightweight fighter able to operate from various classes of ships as a Zeppelin-killer.
The PV7 had a wingspan of only 18 feet, and was powered by an ABC 35hp two-cylinder Gnat engine. It was tested by Major WG Moor in October 1917 but was found to be underpowered and had a ceiling of only 12,000 feet, much too low to engage Zeppelins, some of which routinely operated at altitudes nearly twice as high.
Needless to say, the aircraft was never produced and it was found that other types already in service were adequate for the purpose.
One other aircraft was built by Port Victoria in an attempt to satisfy the above requirements; the PV8 Eastchurch Kitten. Here's a shot of the sole PV8, N540:
I don't know much about this aircraft, but I believe that it was as dismal a failure in it's intended role as was the PV7.
Quagmyre has asked to host the next quiz, so I hand it over to him...
Fade to Black...