A small seaplane takes off from the roof of a large flying boat.
Titles read: "PICK-A-BACK PLANE demonstration flight".
Various shots on the River Meadway of the Short Mayo Composite large flying boat Maia with the smaller seaplane Mercury on her back. The plane takes off from the river and flies over Rochester with the other boat still attached, then the smaller one takes off while in mid-air. These shots are intercut with brief shots of people watching from the ground. The two aeroplanes land separately on the river.
Commentator explains this demonstration has solved the problem of launching long range planes (like Mercury) and is the work of designer Major Robert Mayo. Brief shots of the pilots of the two seaplanes, John Parker and Harold Piper.