Ditching

A water landing is, in the broadest sense, a landing on a body of water. Some aircraft such as floatplanes land on water as a matter of course.

The phrase "water landing" is also used as a euphemism for crash-landing into water an aircraft not designed for the purpose, an event formally termed ditching. In this case, the flight crew knowingly make a controlled emergency landing on water. Ditching of commercial aircraft is a rare occurrence.

Seaplanes, flying boats, and amphibious aircraft are designed to take off and alight on water. Alighting can be supported by a hull-shaped fuselage and/or pontoons. The availability of a long effective runway was historically important on lifting size restrictions on aircraft, and their freedom from constructed strips remains useful for transportation to lakes and other remote areas. The ability to loiter on water is also important for marine rescue operations and fire fighting. One disadvantage of water alighting is that it is dangerous in the presence of waves. Furthermore, the necessary equipment compromises the craft's aerodynamic efficiency and speed.

Early manned spacecraft launched by the United States were designed to alight on water by the splashdown method. The craft would parachute into the water, which acted as a cushion to bring the craft to a stop; the impacts were violent but survivable. Alighting over water rather than land made braking rockets unnecessary, but its disadvantages included difficult retrieval and the danger of drowning. The NASA Space Shuttle design was intended to land on a runway instead. Some future spacecraft are planning to permit water alightings (SpaceX Dragon, Boeing CST-100, etc.)

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