Wing loading

Wing loading, similar to disc loading, describes how much weight is being carried per area of wing. Heavily loaded wings are comparatively small compared to the size and especially weight of an aircraft. Lightly loaded wings tend to be relatively large.

In general, a heavily loaded wing is best suited for high-speed flight because the smaller wing area causes less drag. Heavily loaded wings require large take-off and landing speed because the relatively small wing cannot generate sufficient lift to keep the aircraft aloft at very low speeds. Heavily loaded wings are found on fighter jets and also on commercial passenger jets and turbo prop aircraft.

Lightly loaded wings are best suited for situations demanding low take off and landing speeds as well low stall speeds, meaning an aircraft with a lightly loaded wing can fly at much lower speeds than a heavily loaded aircraft. The comparatively larger wing of such an airplane causes far more drag (and lift) than a more heavily loaded wing and so reduces the speed of an aircraft.

Birds are very good in switching between heavily and lightly loaded wings because they can easily fold their wings in flight. Some raptors can transform their wings from fully extended for easy gliding in thermals, to almost fully retracted for rapid pursuits of prey, often in dives.

Aircraft, especially the more complex variety such as expensive fighter aircraft and commercial jetliners, have certain means to effectively increased or decrease their wing area, using so called flaps and slats. These are devices at the trailing or leading edge of a wing respectively and can be extended or retracted, changing the nature of the wing from a more heavily loaded to a relatively more lightly loaded. However, there are limits to this and even a highly complex airliner with all slats and flaps extended, without any cargo or passengers on board, still has to fly at more than 100 mph / 160 kph to stay in the air.

The switchblade mechanism of SkyCruiser and SkyProwler takes aerodynamic transformation to its extreme. In the VTOL configuration the rotors carry the aircraft's entire weight, effectively reducing wing loading to zero, meaning the aircraft can hover. In the flight configuration the wing carries all the weight and since SkyCruiser has a fairly small wing, this means that speed is high.

In nature only few creatures are able to hover and to fly fast. Hummingbirds are one example, and so gave rise to the Krossblade logo.