Today, most operational helicopters are on skids, wheels, and (where needed) floats. But during the early days in the development of helicopters, the vast majority were constructed with a wheeled undercarriage. This was likely due to the thinking that helicopters would mainly operate from airports.

What are wheels for in a helicopter?

Wheels are generally fitted to large helicopters to allow them to be maneuvered easily on the ground and prevent their rotor wash spraying dust and debris around while taxiing. The extra weight, moving parts, and cost make wheels prohibitive on the smaller, lightweight helicopters.

How many wheels does a helicopter have?

Heavy-lift helicopters, for example, use four wheels to simplify loading. But most others use only three, the single being either a trail wheel or a nose wheel. Sikorsky had equipped the U.S. Army's Black Hawk with a far-aft tail wheel to protect the back end from accidental ground strikes in nap-of-the-earth flight.