RAF Radial Engine Cowlings

[Dave C]

Was it a WW2 RAF safety requirement for the front of the cowling forward of the exhaust collector ring to be painted white?

Aircraft so fitted with Bristol Mercury, Pegasus, Perseus, Taurus & Hercules engines included:

Blenheim 1/1V/V, Lysander, Wellesley, Master 11, Sunderland, Hampden, Botha, Wellington, Stirling, Lancaster 11, Halifax 111, Beaufort 1 & Beaufighter

The FAA did not appear to require Skuas, Rocs & Albacores to be so painted thus, nor were US built Wright and P & W powered aircraft; Fortress, Catalina, Liberator, Hudson, Ventura, Harvard, Boston, Mitchell, Marauder, Dakota, Maryland, Baltimore, Wildcat, Hellcat, Corsair & Avenger

[tempestfan]

It's not painted white (though often depicted as such, see Airfix S.79 artwork), but it's the part in front of the exhaust collector which does not get discoloured by heat. There are I think several threads here on the topic, a recent one must have been in spring.

[Graham Boak]

US engines did not have forward collector rings, only Bristol engines, where it formed part of the cowling in order to improve cooling and reduce drag.  It formed an equivalent to the US NACA cowling seen on the types you mention.  Qualification: some of the smaller, older, US engines did have forward collector rings as seen on the Boeing/Stearman Kaydet, but these were smaller in diameter and did not form part of the cowling design: such aircraft usually (though not always) lacked cowlings.

 

I don't think that all Bristol engines had anything before the collector ring, I think this a later innovation.  The collector ring and this forward piece were often painted white on Coastal Command patrol aircraft to improve the camouflage, and painted black on night bombers to reduce the glow from a hot exhaust. 

 

 

[tempestfan]

This  is one thread which explains really well what is going on, but I thought we had another one this spring...

[Graham Boak]

We have treat this before, but not from this misunderstanding.  Besides, I was already writing this when you posted, so I carried on.