The Bristol Racer Type 72, illustrated in the form in which it made its second flight, embodied a number of advanced features but was flown only eight times in 1922.
It had a retractable undercarriage - which withdrew into the fuselage - and the Jupiter engine was totally enclosed.

The Columbia XJL-1 was built to Grumman designs as a potential successor to the J2F-6 "Duck" as a general utility amphibian.