From Kerbal Space Program Wiki
The Gull is a seaplane. It can be used to train new players when landing on water.
|“|| A small and light seaplane, the Gull makes an excellent basic trainer for kerbals who aren't exactly sure when or where they will be landing (or "landing"). It can take off and land at shockingly low speeds (slower than some hotrodded rovers seen being driven around KSC by certain unnamed test pilots) thanks to its inner-wing flaps..