Painting the Aft Side (backside) of a Propeller

Sorry to have somehow overlooked your post when it was fresh. I know those thundering silences instead of replies can be discouraging.

Don't know about the Spitfire specifically, but most often when the rear surfaces are painted differently, it is to minimize glare and any visual distraction from the turning prop...in that case, usually something like flat black. (When the early Spits had unpainted blades, that would likely have been the case.)

The red-brown is new to me...but I'm a punter, not any kind of expert. Perhaps one of those more familiar with the ins and outs will chime in.

It happened on some aircraft types. I can say about the Spitfire though. But many Japanese aircraft types, especially early war, had the front of the blade in bare metal and the back side in either black or red brown primer. 

stikpusher

It happened on some aircraft types. I can say about the Spitfire though. But many Japanese aircraft types, especially early war, had the front of the blade in bare metal and the back side in either black or red brown primer. 

 

Many US planes also had metal props natural finish on front and black on rear, to reduce glare.

The red/brown color on Spitfires may have been wooden props.  Some early Spits did have wooden props, but they were soon replaced after war started.

Don Stauffer

 

 

stikpusher

It happened on some aircraft types. I can say about the Spitfire though. But many Japanese aircraft types, especially early war, had the front of the blade in bare metal and the back side in either black or red brown primer. 

 

 

 

 

 

Many US planes also had metal props natural finish on front and black on rear, to reduce glare.

The red/brown color on Spitfires may have been wooden props.  Some early Spits did have wooden props, but they were soon replaced after war started.

 

 

Pre WWII US aircraft had bare metal blades. But the two different services marked them differently. The Army left theirs completely bare, with only the manufacturers mark on the front side, and the back side remained bare metal, and there were no tip markings.

The Navy also had the manufacturers logo on the front side of bare metal blades. But they added three color warning stripes to the front and rear sides of the tips: blue, yellow, & red. And the outboard aft side of the blades that would be visible to the pilot were were painted black. The Marines, being part of the Navy, used this same system.