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View Full Version : Swept wing 'dog-tooth'


Double Zero
11th Oct 2008, 14:10
Can someone please explain to me the purpose of the 'dog-tooth' seen in the leading edge of later versions of the Hunter, Kestrel/Harrier etc...

I can well imagine it working to prevent span-wise flow, in much the same way as a wing fence, but imagine it moved the centre of pressure ?

I know both aircraft were said to suffer from 'pitch up' into hard turns, and the dog-tooth was a partial cure.

More confusingly, the dog-tooth was partially blended out on the Sea Harrier FRS2 - later FA2; or at least on the development aircraft I saw.

BOAC
12th Oct 2008, 02:36
~It creates a vortex at higher AoA which acts as a BL reviver and spanwise flow barrier, I seem to recall? I cannot see the cofp move would be at all significant and in any case would it not be the wrong way?

Double Zero
12th Oct 2008, 14:21
Thanks BOAC,

much as I suspected.

I know what you mean about any centre of pressure move being the wrong way, but might help against pitch up ?...

Then again the Hunter suffered from nose down when firing guns, so had blast deflectors pointing downwards !

Strikes me some people are never satisfied...

DZ

k12479
12th Oct 2008, 15:44
BOAC,

What's a 'BL reviver'?

Brian Abraham
12th Oct 2008, 17:25
Energising the boundary layer.

Double Zero
12th Oct 2008, 18:16
'Energising the boundary layer' - in plainer words, keeping the airflow over the wing, rather than let it separate (stall); also achieved by the tiny vertical fins seen in rows near the leading edge, Vortex Generators.

k12479
13th Oct 2008, 17:20
Ok, thanks guys.

FE Hoppy
6th Nov 2008, 16:03
Is it properly known as "dog tooth" or "saw tooth"?

ICT_SLB
7th Nov 2008, 01:07
IIRC it was known as a "sawtooth" on the F.6 Hunter.