Editing VTOL (section)

===Helicopter===
{{Main|Helicopter}}
The helicopter's form of VTOL allows it to take off and land vertically, to hover, and to fly forwards, backwards, and laterally. These attributes allow helicopters to be used in congested or isolated areas where [[fixed-wing aircraft]] would usually not be able to take off or land. The capability to efficiently hover for extended periods of time is due to the helicopter's relatively long, and hence efficient, rotor blades, and allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft could not perform [[Cyclogyro|at least as well until 2011]].

On the other hand, the long rotor blades restrict the maximum speed to about {{Convert|250|mph|kph}} of at least conventional helicopters, as [[retreating blade stall]] causes lateral instability.