On some Hawker Hunters, there is a zig-zag on the leading edge of the wing, as shown below.
Why do only some Hawker Hunters have this feature, and what is it for?
Cirrus incorporates this design into their wings as well. Quoting from their site:
The outboard section of the Cirrus wing flies with a lower angle of attack than the inboard section. When the inboard section, which produces much of the lift, stalls the outboard section, where the ailerons are, is still flying. The result is that a stalled Cirrus airplane can be controlled intuitively using aileron.
After doing a little more research I found the answer.
Quote from wikipedia:
A dogtooth is a small, sharp zig-zag break in the leading edge of a wing. It is usually used on a swept wing, but also on straight wings ("Drooped Leading Edge" arrangement), to generate a vortex flow field to prevent separated flow from progressing outboard at high angle of attack. The effect is the same as a wing fence.
Where the dogtooth is added as an afterthought, as for example with the Hawker Hunter and some variants of the Quest Kodiak, the dogtooth is created by adding an extension to the outer section only of the leading edge.
As an added piece of information, this feature may have something to do with the fact that the Hawker Hunter, for many years, was the only swept wing fighter that could be reliably recovered from an inverted spin.
For this reason the Empire Test Pilot School at Boscombe Down used one for advanced training purposes (and may still do so).
On some Hawker Hunters, there is a zig-zag on the leading edge of the wing, as shown below. Why do only some Hawker Hunters have this feature, and what is it for?
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