Development of the Hillman Imp

Aerodynamics

Part of Kenneth Sharpe's memories

• Apex 3
• The Asp

Apex 3

KS0899: The car is Apex 3 (I think) in the wind tunnel at MIRA. The wool tufts are to indicate the direction of air flow and the rubber tubes are connected to manometers to measure the pressure.

Advanced Design Department
An Advanced Design Department was set up at Stoke. Earlier in the 1950's, in order to increase facilities for the whole group, a cold room that would accept a whole car was built in this same workshop. And serious consideration was given to constructing a wind tunnel at the rear of the test cells. This would have been very expensive, money was tight and in any case there was a much better one at M.I.R.A.

Cooling at max speed
Many different fan and cowl designs, including a reversed flow set-up, were tried in the attempt to provide adequate cooling for high speed running, without absorbing too much engine power.

Wind tunnel
Wind tunnel tests were another of those tests that had to be carried out during the evening. Apparently the electrical load caused by the 4 huge motors that drove the propellers resulted in a mains voltage drop in the area, so the wind tunnel could only be used 'off-peak'.
Most of these tests were in connection with the Imps known sensitivity to cross winds and of course the high-speed cooling problem. One of these tests brought the unexpected finding that the Imp van was less affected by crosswinds than the saloon.

KS0900

KS0898

The Asp

KS5211-34

KS5211-26