The USA interwar planes (3 Viewers)

[Dana Bell]

Just to clarify for anyone, this is a DC-5. Not an Douglas RD-3. Its the "RD3-1 DC-5"

I thinks we're all having a problem with those pre-1962 Navy designations today - that should read "R3D-1!"

 

[GrauGeist]

I thinks we're all having a problem with those pre-1962 Navy designations today - that should read "R3D-1!"

The old system was fairly easy to decipher, though.

R - transport (single engine transports were denoted by the letter G)
3 - third type in class by manufacturer accepted
D - Douglas (manufacturer)

The dash 1 would indicate a sub-type or used as a placeholder in case of additional subtypes.

Surprisingly enough, the Imperial Japanese Navy's system was nearly identical.

 

[OldGeezer]

Dislexcia

And actually it's R3D, not RD3...

 

[Gnomey]

Good shots!