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JulianEdgar · 05-19-2020, 04:02 AM

I received some more GOE222 aluminum aerofoil today - two 1.6m (5.25ft) lengths.

For interest's sake, I thought it might be good to have the aerofoil projecting vertically through the sunroof of my wife's car, as she drove at 50 km/h (31 mph).

By rotating the aerofoil I could then get a (literal) feel for the forces involved. It was quite fascinating.

It was easy to set the aerofoil to an angle where basically no drag could be felt, but by rotating it a little you could get an amazing amount of sideways force (ie lift or downforce if the wing were horizontal).

I was really surprised with how hard it was to stop it moving sideways. That's what it wanted to do - as the official lift/drag figures show, even when developing max lift/downforce, the drag isn't very high (ie it didn't much want to move backwards).

So no figures (I have done 'proper' measurements on multiple other occasions with this extrusion) but a startling indication of the forces that can be developed.

So there's a test I haven't done before.

05-19-2020, 04:02 AM	#10 (permalink)
JulianEdgar Banned Join Date: Nov 2017 Location: Australia Posts: 2,060 Thanks: 107 Thanked 1,605 Times in 1,136 Posts	I received some more GOE222 aluminum aerofoil today - two 1.6m (5.25ft) lengths. For interest's sake, I thought it might be good to have the aerofoil projecting vertically through the sunroof of my wife's car, as she drove at 50 km/h (31 mph). By rotating the aerofoil I could then get a (literal) feel for the forces involved. It was quite fascinating. It was easy to set the aerofoil to an angle where basically no drag could be felt, but by rotating it a little you could get an amazing amount of sideways force (ie lift or downforce if the wing were horizontal). I was really surprised with how hard it was to stop it moving sideways. That's what it wanted to do - as the official lift/drag figures show, even when developing max lift/downforce, the drag isn't very high (ie it didn't much want to move backwards). So no figures (I have done 'proper' measurements on multiple other occasions with this extrusion) but a startling indication of the forces that can be developed. So there's a test I haven't done before. Last edited by JulianEdgar; 05-19-2020 at 05:28 AM..