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Old 11th October 2008, 16:10   #1 (permalink)
Double Zero
 
Join Date: Mar 2006
Location: West Sussex
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Swept wing 'dog-tooth'

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.

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Old 12th October 2008, 04:36   #2 (permalink)
Per Ardua ad Astraeus
 
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~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?
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Old 12th October 2008, 16:21   #3 (permalink)
 
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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
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Old 12th October 2008, 17:44   #4 (permalink)
 
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BOAC,

What's a 'BL reviver'?
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Old 12th October 2008, 19:25   #5 (permalink)
 
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Energising the boundary layer.
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Old 12th October 2008, 20:16   #6 (permalink)
 
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'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.
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Old 13th October 2008, 19:20   #7 (permalink)
 
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Ok, thanks guys.
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Old 6th November 2008, 18:03   #8 (permalink)
FE Hoppy
 
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Is it properly known as "dog tooth" or "saw tooth"?

Last edited by FE Hoppy : 10th November 2008 at 22:58.

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Old 7th November 2008, 03:07   #9 (permalink)
ICT_SLB
 
Join Date: Apr 2002
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IIRC it was known as a "sawtooth" on the F.6 Hunter.

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