Part of engine attached to propeller?

[Pete_Homer_AK]

This question was posted in "aircraft requests" but thought it might be more appropriate in the "engines" forum. This propeller has part of an engine attached...reduction gears? Can you speculate from the photo what kind of engine it came from? The following link is to the original post and the second to a site with a number of photos:

Mystery Prop Needs ID

Photos of Mystery Prop

My apologies if I violated rules by posting same question in two forums.

 

[FLYBOYJ]

This propeller seems to be attached to a spline that is part of a reduction gear box

 

[Dogwalker]

Is a reduction gear of the planetary type, with part of the aluminium hull of the gearbox. The planetary reduction gear and the domed hull mean that almost surely the engine was a radial one (with few exceptions, inline engines used plain reduction gears).

 

[Pete_Homer_AK]

Thanks for the info flyboy and dogwalker. I didn't know there was part of the engine remaining on the prop.

I believe that the prop attached to the reduction gear, 23E50/6477A-0, was used with these two engines. Web search for B-24D and C-47/DC-3 1830 engines photos look like the ones in this post. B-17E's used the 1820 engines which also look pretty much the same. Any opinions?

 

[kmccutcheon]

The reduction gearing is that of a P&W R-1830. The propeller hub is Hamilton Standard 23E50. Cannot identify the blades.

 

[Pete_Homer_AK]

kmccutcheon, Do I understand you correctly that this reduction gear is definitely NOT part of an 1820 and is confirmed to be from a 1830? An important point in that it will eliminate an aircraft from consideration. BTW the blade is marked by stencil as a 6477A-0 so no doubt on that issue. Thanks for the information.

 

[kmccutcheon]

Do I understand you correctly that this reduction gear is definitely NOT part of an 1820 and is confirmed to be from a 1830?

Correct. The image below depicts the Wright R-1820 propeller gear reduction scheme: crankshaft drives ring gear; planet gears in fixed carrier; planet gears drive propeller shaft.

 

[Pete_Homer_AK]

Thanks KMC for the clarification! This is very helpful information.

I'm really going to push my luck on this thread and ask two more questions. Is it possible to tell if it came from an R-1830-42 or R-1830-92?

Could you tell me what the difference is between those two engines?

 

[kmccutcheon]

Is it possible to tell if it came from an R-1830-42 or R-1830-92?

You might be able to identify aircraft that used blades with the same designation as yours, and backtrack to engine candidates. The only information I have is for a 23E50-233 hub with 6447A-0 blades that completed an Army Type Test on 13 Oct 1943 and was approved for use on P&W R-1830-33, -43, -65, and R-2800-5.

Could you tell me what the difference is between those two engines?

I am unable to find any reference to an R-1830-42. Information on the R-1830-92 can be found by visiting the Index of Twin Wasp and R-1830 Designated Engines.

 

[Pete_Homer_AK]

KMC

Looking back on my research it seems I got mixed up between the Wright Cyclone engines and Pratt Whitney Twin Wasp engines. I think I got it straightened out and here is the corrected data.

The 23E50/6477A-0 propellers were used on many aircraft during ww2 but the ones that were present in the Aleutian Islands during ww2 are the B-17E, B-24D, and C-47. Engines used by those aircraft were:

B-17E (Wright Cyclone R-1820)
B-24D (P&W R1830-43)
C-47 (P&W R-1830-90C) aircraft.

With your help I am able to eliminate the B-17E from consideration because the mystery prop does not have the R-1820 reduction gear attached. The choice left is between the bomber and cargo plane. Looking at the photos, is it possible to tell if the prop has an 1830-43 or 90C reduction gear attached to it?

Thanks for your valuable help and my apologies for the mix up. I am a novice at all things aviation and have much to learn.

Pete

 

[kmccutcheon]

Looking at the photos, is it possible to tell if the prop has an 1830-43 or 90C reduction gear attached to it?

Unfortunately, no. Both the R-1830-43 and R-1830-90C have 16:9 propeller reduction gear ratio, and hence, identical reduction gear construction.

 

[Pete_Homer_AK]

I had a hunch that was the case. But you helped reduce the field of candidates by one. Thanks!