enginehistory.org

[ktowne]

Hi Everyone....

I was given a single prop blade a few months ago and am working on a restoration for cosmetic display. I'm trying to identify the blade and maybe tag a definitive a/c type to it. It was in pretty rough shape with some important parts of the stenciling obliterated by rust. As best I can make out the data is as follows:

Blade Ser no. 57440
Blade Assem. A20A-15?-?
Low Angle 42 In.Rad.26.0
High Angle 42 In.Rad.60.5

As you'd expect the stencil is all caps. I've hammered the web as hard as I can for leads (which is how I found the web site here!) and come back with similar assembly numbers but the A20A designation is making it difficult.

Based on the blade nut and bearings removed from the shaft it appears to be an Aeroprop but darned if I can find any other identifying marks beyond the stencil.

Can anyone shed some light on this or point my search in a better direction?

Here is a link to a photo of the blade if anyone would like to look closer at the stenciling.

The Blade

Best to All...

Kenny

[tfey]

Kenny,

I think you are correct in believing it is an Aeroprop. Can you post a picture of the base of the blade? Aeroprop blade roots are very distinctive (hollow; pegs on the periphery) and the corrosion indicates steel. Aeroprops were hollow steel and will sound "bong" hollow when rapped which a knuckle.

The A20A-155-XX blades are listed as being used on the AD7652 contra-rotating blade sets used on the Fisher XP-75 of 13 foot 1 inch diameter. The A20A-156-XX blades were used on the AD7562 contra-prop sets used as test clubs on the Allison V-3420B. This means your blade should be somewhere around 55 inches in length. Email me at Doolittlefey@aol.com.

Tom Fey

[ktowne]

Wow, this was a pleasant surprise! From the threads at the bottom to the tip it measures 74 1/2". There is a ring a bit up from the base and it's 65" from there to the tip.

PM on the way shortly!

Thanks a bunch for the reply!!