The Parnall Peto was a small seaplane designed to the British Air Ministry's specification 16/24 in the early 1920s for use as a submarine-carried reconnaissance aircraft.

Of mixed wood, fabric, aluminium and steel construction, it had unequal span, Warren-braced folding rectangular wings.

Performance was generally satisfactory but following crash damage, improvements were made and the machine was rebuilt with new wings, metal floats and a 169 hp Armstrong Siddeley Mongoose engine.

Tests both on the sea and in the air showed that designer, Harold Bolas, had met the requirements and it was officially judged to be exceptionally good.

The aircraft was launched using a compressed air catapult mounted on the forward casing of the submarine and recovered using a crane.