Skirt legality

[matt21]

I had a discussion with some other people about the legality of skirts back in the heydays of groundeffect.

Does anybody know how these things were made legal under the "non-movable-aero"-rule?

Even Peter Wright said it is some kind of mystery how they could run these?

[Tommy Cookers]

the 'slightly flexible' underbelly 'air dams' of the 1975 BT44b were legalised by a rule clarification ? (the team owner was Mr Ecclestone)
they gained DF but this mainly benefited drag, the rear wing DF being reduced in the interest of car balance
the BT44 having started this by using a dam under the nose
the BT44b underbelly position was intended to reduce wear due to pitching

McLaren M23 adopted the idea in 1975 using a more flexible plastic (maybe they had requested the rule clarification ?)

then Lotus saw that this allowed a ground effect that actually worked, and so made history
others (March and Peter Wright pre-Lotus ?) having tried a venturi-based ground effect without sealing skirts

[matt21]

Which rule are you referring to?
I looked for 1977/78 regulations but could not find any.

[gridwalker]

Take a look through this short thread on the topic : http://www.f1technical.net/forum/viewto ... =6&t=10643

EDIT : wait, that topic was started by the OP for this thread.

Haven't you found any additional info since 2011? We need to get some solid info in here ASAP!!!

[matt21]

Haven't you found any additional info since 2011? We need to get some solid info in here ASAP!!!

I was searching from time to time, ran through books, but couldn´t find anything. That´s the reason why I started another thread. Maybe I should have revived the old one.