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  • Just bought (and probably overpaid)

    Hoping someone can identify. My wife had to have it
    Attached Files

  • #2
    I'm not near my reference material to look that up, but it's a nice looking prop, probably from the 30s to 50s era.

    Are there any other stampings on it?

    Comment


    • #3
      Wow. Thanks for your reply. Yes. Other stamping on other side of hub reads 370618. I was guessing it is a 1937?

      Comment


      • #4
        I think the other number is a serial number, not reflecting a date of manufacture.

        When I'm home next time I'll try to look up that Type Certificate number ("ATC 87") and might be able to find the design number ("80A"). Those are the identifying markings. Is the prop 80 inches from tip to tip?

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        • #5
          No this prop is 9 feet

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          • #6
            So it's clearly not a Sensenich prop, and the manufacturer isn't clear, so we may not be able to identify it. I'll look for the type certificate information and see if I can come up with anything.

            The metal sheathing is also a little different than you commonly see, so that might lead to some more manufacturing information if you can find an identifiable prop with the same type of sheathing.

            Comment


            • #7
              Thanks. Do you think because it is 8 hole and 9’ it may be older?

              Comment


              • #8
                Originally posted by Emerson View Post
                Thanks. Do you think because it is 8 hole and 9’ it may be older?
                That's certainly possible, although "older" may just be 20s or 30s, when aircraft technology was evolving quickly. See this page and carefully measure the hub dimensions. It will eliminate a number of engines and narrow down the aircraft possibilities.

                "Overpaid" is relative, especially when the wife is pushing you to buy it.

                Comment


                • #9
                  Thanks. I will have to measure at a later day. We bought at auction out of our area and we left it at my brother in laws house. I’ll have home measure.

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                  • #10
                    I assume this prop is American? My interest is British and German props from WW1, so I'm not really qualified to comment on this prop except to note that the brass sheathing is the most extensive I have seen on a prop.

                    Brass sheathing is used to protect wooden props from FOD such as twigs, loose grass and leaf litter thrown up by the wheels of the aircraft into the rotating arc of the prop, causing erosion to the prop blades.

                    On tractor props, a small brass leading edge is sufficient. On pusher aircraft with the engine behind the pilot much more of the FOD thrown up by the wheels can reach the propeller disc, and the size of the brass sheathing is much larger. This also applies to seaplanes.

                    So my minor observation is that your prop was intended to be used where lots of FOD existed. This would include mud, grass, and twigs; snow and ice; and lastly to seaplanes or flying boats where spray and bodies of water could be thrown up in the path of the prop.

                    The witness marks around the bolt holes show that the prop is a flown example. The construction of the prop with large laminations suggest that it was built in the 1920's.

                    The riveting holding the brass sheathing to the prop suggests the style of AAD Lang in Britain who devised the use of such protective sheathing using counter sunk screws which were then filled by a small amount of silver solder which was then smoothed to maintain the aerodynamic surface. He patented the design in GB in 1913 and in the USA in 1915.

                    In 1917, when the USA entered WW1, Lang was loaned by the British Admiralty to the USN to advise those US firms competent in wood-working that were recruited to make aircraft propellers in volume.

                    There's a lot of supposition in what I have written above and you should not regard it as anything more than an exploration of possibilities.

                    With kind regards,

                    Bob
                    Last edited by Bob Gardner; 08-10-2019, 02:11 PM.
                    Bob Gardner
                    Author; WW1 British Propellers, WWI German Propellers
                    http://www.aeroclocks.com

                    Comment


                    • #11
                      Bob may be correct about the 1920s. I've looked through the list of Type Certificates and could not find ATC 87 listed, but there are very few two digit Type Certificates, as most are three digits. So my guess is that this one was approved early on in the type certification process, although I don't know when that was instituted for propellers.

                      Comment


                      • #12
                        Finally picked it up

                        Hi All! I posted 1-2 months ago. I bought a prop at an auction that my wife had to have. Finally picked it up. Here are additional pics. Hope someone can finally figure this out
                        Attached Files

                        Comment


                        • #13
                          Emerson,

                          The data should be stamped on the side of the hub. I need it to identify the drawing number and hence the aircraft for which it was designed.

                          The shape of the prop with the trailing edge describing a straight line through the hub is in the style of Lucien Chauviere, who was the founding father of propeller design. It might therefore be made by his company, the Integrale Propeller Company, although several other prop makers followed his ground work.

                          With kind regards,

                          Bob
                          Bob Gardner
                          Author; WW1 British Propellers, WWI German Propellers
                          http://www.aeroclocks.com

                          Comment


                          • #14
                            Please see pics for the only markings on the prop. Thanks
                            Attached Files

                            Comment


                            • #15
                              Emerson,

                              I regret that I have nothing similar in any of my databases, so cannot advise. However, I think those markings are British and date from the 1920's-1930's.

                              Perhaps one of our experts, Pierre Michel Decombeix in France, or Dave Bahnson in America will be able to help.

                              With kind regards,

                              Bob
                              Bob Gardner
                              Author; WW1 British Propellers, WWI German Propellers
                              http://www.aeroclocks.com

                              Comment

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