View Full Version : Hartzell prop

12-30-2014, 11:36 AM
Hi, I have a Hartzell propeller that I will soon be selling. I am hoping someone on here can tell me what it was used on and an approximate value. This prop does have decals stating McCook Field. It was also purchased in the Dayton Ohio area. Any help is appreciated. Thanks.

12-30-2014, 06:33 PM
Often, an "X" in the identification number indicates an experimental design, although not always.

I can't read all the numbers from the photos. Can you post them here?

Many of the early Hartzell propellers were made of walnut. I can't tell for sure but does the wood look more like oak?

12-30-2014, 07:47 PM
Hi Dave. Thanks for your quick response.

There are two "R"s opposite from each other on the front (from what I have read here it means it is a right-turn prop). The other identifying marks are as follows:

1. Mc F (McCook Field?) INSP. NO 02700
2. 96X104.5
3. 1654
4. 1 2

The wood does look like oak, but it actually is walnut (you can tell where the wood is bare). I have worked with many different types of wood over the years and would have bet anything this was oak. However, upon closer inspection, one can see it is walnut.

Upon further investigation... McCook Field in Dayton Ohio played a vital role within military aviation (United States Army Air Service) during WWI. That location is rich with aviation history.

Let me know what you think.

12-30-2014, 08:44 PM
My mistake about the "x". I see now that there was a decimal point in the 104.5, which is the pitch of the propeller in inches.

I have a list of numbers sent to me years ago from Jimmie Reedy at Hartzell. There are about 1400 different design listings, mostly by diameter and pitch, and the only listing I could find for a diameter of 96" and a pitch of 104.5 inches in that entire document shows an engine of "300 Hispano" and simply "Racer" under description.

So I think it's highly probable that yours is the propeller described, but unfortunately there is no more specific information other than what is listed. The 300 Hispano refers to a 300 HP Hispano Suiza (http://en.wikipedia.org/wiki/Hispano-Suiza_8), which would point to one of the later 8F models, probably dating to the twenties or thirties.

While I wouldn't consider it likely that more information would turn up, I would HIGHLY recommend that you leave this propeller in its original and unrestored condition to preserve its authenticity as an artifact. You never know. More information may turn up later that helps narrow it down.

12-30-2014, 09:18 PM
Dave, this information is very helpful. Thanks for taking the time to educate people like myself and helping them identify their old propellers.

I had already planned on keeping it in its original condition. It has GREAT patina. Any idea who I could contact for estimating its worth? Let me know.

Thanks again!,

12-30-2014, 10:08 PM
See this page (http://woodenpropeller.com/Values.html) for a general overview.

It's impossible to come up with an accurate "market price", because the market is so small, and it's difficult to find a sale of a comparable prop that has been sold.

Off the top of my head, if I were trying to sell it I think I'd expect ultimately to get something in the $1000 range, but more if it could be linked to a specific aircraft type that was of interest to the buyer.

I'm assuming that the hub has not been carved out for the clock. I think that kerf sawn through part of the hub was to make it clear that it was not airworthy.

12-30-2014, 10:53 PM
I don't think the hub was cut out for the clock.

Thanks to your information about the 300 HP Hispano-Suiza engine, I was able to locate information as to what aircraft that powerplant was used in. Some examples are: Martinsyde Scout F-4, Sopwith Dolphin C1-F1, NiD. 29, B.A.J. C2, Spad XVII-C1, Spad 18-Ca 1-2, Spad 20-C1, De Marcay-C1, Hanriot-Dupont 7-C1, and Nieuport 29-C1. The former owner mentioned he thought it might have been from a Spad XVII-C1, though he wasn't for sure. No matter which one it was from, all of these planes are very impressive.

I'm guessing since McCook Field shut down in 1927, and that this was used there, this must have been from the latter years before it closed.

This is getting really interesting. Thanks for your help. - Dennis

12-31-2014, 07:12 AM
The Hisso engine (which was also manufactured in this country as a "Wright" engine) was widely used on a whole variety of aircraft. The notation in my records that those dimensions were listed as "Racer" leads me to believe that is wasn't used on any of those listed but more likely was used in the development of some sort of speed objective prototype or actual performance racing aircraft.

I also note in those listings that the pitch of 104.5 inches is extremely coarse, like the thread on a screw, and was likely designed specifically for speed. Think of it as a fixed "high gear" for an aircraft engine. Most all of the other listings for diameters of 96 inches have a pitch ranging from around 60 inches to around 90 inches, so this one was clearly above that, and unusual in its degree.

12-31-2014, 12:11 PM
Interesting. I didn't realize, until you pointed it out, that this propeller had that aggressive of a pitch (I had nothing to compare it to). I do understand about pitch. The fact that this is a high-performance propeller from back in the late 20's is fascinating. It coincides with the activities at McCook Field. They engineered all sorts of aircraft there and were always looking to develop faster and more nimble airplanes for use in war. I am now becoming aware at how rare and historically significant this propeller actually is.

Thanks again!

12-31-2014, 08:24 PM
I'm not quite yet convinced that "McF" necessarily means McCook Field, although it's hard to know what else that might mean.

12-31-2014, 11:53 PM
If you look at the first picture, once you zoom in, there is a decal just below the Hartzell decal. It is a pair of white wings with a white star in a blue circle. The decal says McCook Field and the star in the blue circle with the red dot is the symbol for the United States Army Air Service. I am certain (from the information that I have) that this prop is from McCook Field. I am attaching a close-up. It is easier to see in person. Let me know your thoughts.

01-01-2015, 08:19 AM
Thanks, I didn't see that.

01-01-2015, 08:44 PM
Dave, would you please scan and send me a copy of your information from Hartzell pertaining to this prop. I am happy to compensate you for your time. Please send to: ddalby70 at msn.com . I have researched this for several hours today and have found some amazing information (I think the puzzle pieces are coming together).

I found out what the term "Racer" pertains to in the Hartzell listing. They are several planes that competed in the Pulitzer Trophy Races. See link: http://www.aerofiles.com/pulitzer.html . Of these planes, only three used the Wright Hisso H-3 engine. They were the Verville-Sperry R-3 Racers. See here: http://en.wikipedia.org/wiki/Verville-Sperry_R-3_Racer . Also, in 1924, the race was held at Dayton, OH. All three R-3 Racers were from and remained at McCook Airfield. Some of the interesting facts about this plane was it had one of the first retractable landing gear systems. In 1923 it set a world speed record of 167.74 mph with Orville Wright officially observing from the ground. In 1924 it won the Pulitzer Trophy Race. It was identified as one of the "Twelve Most Significant Aircraft of All Time" by Popular Mechanics.

Thanks to your information, and this new information, I will continue to research this topic for a while. Please send me the information from Hartzell when you can.
Thanks for all of your help!

01-02-2015, 09:25 AM
I've emailed that page to you, and also modified your email address format in the above post to avoid it being harvested by bots.

I'm always willing to accept donations to the site via PayPal to dbahnson at gmail.com, and I plan to set up a donations page shortly anyway.