[aerohead]

Originally Posted by freebeard

Le Mans 1955.

https://www.sae.org/publications: The Role of Aerodynamics in the 1955 Le Mans Crash

For $37 they will speculate on whether the air brake was culpable for 16 pages.

It's interesting, in that, Daimler had had access to the FKFS next door to them since 1935 when it opened, and I have images of their 1950s GP car in the FKFS wind tunnel, so we know they had the opportunity to fully-wind-tunnel-test the air-brake before ever heading over the border into France.
The SAE abstract ( which are usually free ) might have enough data to answer some questions. I'll be keeping my $37 for something else.