(July 2011) Can light-sport aircraft be seaplanes? In short, yes. But only as long as the aircraft "intended for water operation" meets and stays within the LSA definition. And, as with land aircraft, that includes meeting a maximum takeoff weight. In the case of seaplanes, the magic number is 1,430 pounds instead of the 1,320 for single-engine land aircraft (see the March column "Why 1,320?"). So why the extra buck ten? We can trace its origin back to the FAA notice of proposed rulemaking process for the Sport Pilot/LSA rule. When deciding on the maximum takeoff weight to accommodate the seaplane structure (hull or floats), the FAA once again looked to the European microlight regulations.