Many of you will have seen, photographed, ridden in or driven Bristol buses fitted with the unusual Cave-Browne-Cave cooling system. So here’s a photo of one of the prototype buses.
This is Hants & Dorset 1068, a 1940 Bristol K5G carrying an early version of the cooling/heating system invented by Wing Commander T. R. Cave-Browne-Cave. He was Professor of Engineering at Southampton University at the time. The photograph comes from my own collection and came to light while I was looking for images for a new book I’m writing.
In a nutshell, the traditional radiator mounted in front of the engine is omitted and two – smaller – radiators are fitted either side of the destination display. These also act as forced air heaters for warming the upper deck. In summertime, when the saloon heating isn’t necessary, the warm air can be deflected through vents on the sides of the bus.
I’m not sure why the Wing Commander was commissioned to create this system because the traditional cooling system had been working reasonably well for decades previously and indeed continues in the same form to this day. Anyway, his first prototype installation was fitted to a Southampton Corporation Guy Arab. The test went well evidently and the second installation was fitted to a Hants & Dorset Bristol K, as shown above. The front cowl, obviously from a Lodekka, was a later modification because the original front was more obviously based on the standard PV2 radiator shape.
Cave-Browne-Cave obviously sold the idea to Bristol Commercial Vehicles/Eastern Coach Works and it was widely adopted as an option for Bristol LDs and F-series Bristols as we all know. Some more of Southampton’s Guy Arabs were also fitted with CBC, as were a few Bristol Ls of West Yorkshire Road Car.