Mercedes W196

[steveaki13]

I was thanking you for passing it on.

[inimitablestoo]

All I know about the W196 slipstreamer is that, having dominated its first Grand Prix in France, Mercedes took the car to Silverstone and found it wasn't brilliant at dealing with the oil drums that were used to mark track limits (hmm... now there's an idea...)! Given that such hazards weren't uncommon at the time - notably the exposed "traffic furniture" on street circuits - it might explain why there were few takers for the slipstreamer shape.

[D-Type]

An all-enveloping body is heavier than an open-wheeler. So the advantage in straight line speed has to be balanced against poorer acceleration. Contrary to what some writers suggest, the open-wheeled version was always part of Uhlenhaut's plans for the car and was not an afterthought. Development of the cars took longer than envisaged as is shown by the fact that they didn't make their debut until Reims. In the end priority was given to the streamliners and the open-wheeler simply wasn't ready in time for Silverstone.

The common story regarding the problems at Silverstone is that the drivers couldn't see the wheels to place the car precisely. I'm not convinced - at the time drivers had no problems in sports cars - visibility to corner a Lister or a Tipo 60/61 Maserati, for example, was as poor as the W196. Weather during the British GP weekend was cold and wet with track conditions varying between wet, damp and dry. The Mercedes team used Continental tyres and Continental were less experienced than Pirelli, Dunlop or Englebert in making racing tyres. In particular their wet weather performance was poor. Apparently under damp conditions the 'break away' of the tyre at the limits of adhesion was sudden rather than gradual and this caught Fangio and Kling out. As aerodynamics was not that well understood 60 years ago, there may have been some aerodynamic instability when the cars were cornering as opposed to running in a straight line.

[D28]

D-Type:
"The works produced a car at Reims for 1959 with a mixture of "Monaco" and "Bobtail" bodywork but it didn't work too well. Significantly they didn't take it to Avus".

This demonstrates that while the W196 streamliner was unsuccessful, the idea of streamlining continued to interest engineers.
The Cooper in question was tested at Silverstone and in Reims for the French GP. It was reported to lift at 180 mph and feeling squirrelly in the curves. A description is given in Cooper Cars by Doug Nye.