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#1883871
Edit: Not sure if breaking GA only rule. But it is aviation related.

Hi, saw this at Duxford recently. It is a Strikemaster, (weaponised Provost).

I guess this stuff on the wing upsets the airflow but what's the point of that?
I reasized the picture. Basically it looks like a load of sand applied on the leading edge of wing, almost pebble-dashed.

Maybe make it more stable for strafing by limiting effects of aileron? :cyclopsani:



#1883878
After uploading I thought perhaps to average performance over the wing as those rocket pods must cause a disturbance (as it starts from that store - probably co-incidence). But it doesn't make sense to complete ruin the lift generated by the wing. Seems totally counter-initiative.
#1883880
On the Maule we had Vortex Generators over the whole wing.

Lower Stall speed
No degrading of Cruise speed
Better roll control
Better elevator control with engine at idle

This picture is not of a Maule but as you see they are standing up angled into the airflow and despite that no degradation of performance - quite the opposite.
Image
#1883955
My memory (so not reliable) of the theory is that laminar flow of air over the wing is good, but ...

At some point, depending on the aerofoil section, the airflow breaks away from the wing, becoming turbulent. This generates lots of drag.

So the designers disrupt the airflow a little before that point - this keeps it attached to the wing, though less smooth, and overall more lift is generated.
StratoTramp liked this
#1884097
When the Mk5 Jet Provost was undergoing flight testing, it was found that, unlike the Mk3 and Mk4, it had unruly stalling characteristics and an oscillatory spin.

The stalling behaviour was fixed by small fixed leading edge slats at the wing root and 'moustache' nose strakes. The spinning behaviour was tamed by roughened outboard leading edges, which eliminated the oscillatory characteristic.

RAF Mk5 aircraft fitted with tip tanks used for navigator training didn't need any of these aerodynamic bodges, so I'm surprised that the Strikemaster in question has roughened outboard leading edges.

Great little jet, the JP!!
StratoTramp liked this
#1884248
nickwilcock wrote:When the Mk5 Jet Provost was undergoing flight testing, it was found that, unlike the Mk3 and Mk4, it had unruly stalling characteristics and an oscillatory spin.

The stalling behaviour was fixed by small fixed leading edge slats at the wing root and 'moustache' nose strakes. The spinning behaviour was tamed by roughened outboard leading edges, which eliminated the oscillatory characteristic.

RAF Mk5 aircraft fitted with tip tanks used for navigator training didn't need any of these aerodynamic bodges, so I'm surprised that the Strikemaster in question has roughened outboard leading edges.

Great little jet, the JP!!


Forgot to check back in on this for a few days. This is really interesting.

Thanks to everyone else for taking the time to pontificate too :thumleft: