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chinaprop
02-24-2016, 02:38 PM
Hello Forum members,

I am new to this forum and happy to meet you all online. I happen to come across and bought a wooden propeller and would like to find out which plane it belonged to. It is damaged and likely replaced here on the island of Faial, city of Horta on the Açores. I know this was an important stop for the early races for records and if a plane was damaged or parts were replaced it is nice to find such provenance and get pictures from the photo archives.

It is damaged, has some cracks in it but I want to leave it exactly as is. On the back it looks that there has been paper pasted on it once and on the front there is some left which I left as well.

The length is approx 11,3 Ft (338.05 cm) The bore hole is approx 4,5 inch (10.3 cm) and it has 8 holes in the middle.

Copper lining on the front. I can email pictures of it. It says Dornier on both tips with a plane that looks like a compass rose in red and black

Bob Gardner
02-24-2016, 04:37 PM
Welcome to our forum.

Your Dornier propeller is very rare. I think I have only seen one other example which is in SDTB in Berlin (the new name for DTMB). A diameter of 3380mm is large and suggests a powerful engine and that it was for a post WW1 passenger aircraft. Some of the laminations are missing. The extensive metal sheathing suggests it may have been made for a seaplane,

Dornier was founded c1923 from the ashes of the Friedrichshafen and Zeppelin companies. They made both conventional aircraft and seaplanes.

Are there any markings stamped on the hub or blades? ( I think probably not on the hub because of the missing laminations.)

With kind regards,

Bob

Bob Gardner
02-24-2016, 05:00 PM
Postscript; the fact that you found it in the Azores suggests it might well be from a Dornier flying boat, even from the famous Do X flying boat. (For other forumites the Azores were a stopping point for much of the air traffic across the Atlantic between the wars. )

Bob

chinaprop
02-24-2016, 05:29 PM
Thank you Bob for your response. Yes it must have been a seaplane maybe we can find out which one as there were not that many landing in Horta. There are no markings other than the Dornier logo´s on it. It looks like missing lamination but as they are exactly the same on both sides of the hub I think there was an aluminium assembly to hold it. What intrigues me is that there is paper glued to it as you see on the tip. The back is the same. Could it have been a spare they kept here? for these seaplanes?

chinaprop
02-24-2016, 05:39 PM
Considering the paper stuck to it it might have been a spare part as if I am correct Lufthansa wanted to open a route through the Azores across the Atlantic. I have to search wich plane they intended to use. It would make sense to have spares along this proposed route.

Bob Gardner
02-25-2016, 06:47 AM
Looking at your photographs again, it has dawned on me what I should have seen earlier. Your prop may not be missing two laminations. It is particularly thin because it is half of a four bladed propeller. Large four bladed propellers were obviously bulky and difficult to ship anywhere. Two halves occupied much less space. This is exciting because the Dornier Do X had four bladed propellers. But I know very little about Dornier flying boats. It might be that all of them used four bladed propellers comprising 2 x 2 bladed prop. But if not, it is possible that your propeller is from a Do X. Let us know what you discover on Google etc!

With kind regards,

Bob

Dbahnson
02-25-2016, 09:49 AM
Bob, I think there was another reason for 4 bladed props being stacked 2 bladed props. It allowed tolerance for expansion and contraction of the wood without creating defects in the wood or the glue joints themselves. Any of the very old 4 bladed props I've owned have shown weakening of the joinery at the hub over time. I think with the stacked blades that process is accommodated by the stacking arrangement, so that the grain in each blade remains lengthwise.

You can see it on the edge of this FE8 prop, but it's extensive throughout the hub.

http://woodenpropeller.com/images/FE8h6.jpg

Actually, here's a better view of the same prop.

http://woodenpropeller.com/forumvB/attachment.php?attachmentid=5988&stc=1&d=1456408089

chinaprop
02-25-2016, 10:08 AM
Hello Bob,

That would be really exciting and it makes sense to have some sort of connection on these locations be it aluminium or wood. I send an email to the museum in Berlin, they might know more. As far as DO x arrivals here I can check the library archive in Horta, might find more there than on Google. There must be a list of Do X planes arriving in Horta.

I also thought it could be a push propeller but could not find any info on that.

Th only length I could find for the DO x prop is 355 cm but as different engines might have been used with different optimum rpm speed the prop might have come in different lengths.

Dbahnson
02-25-2016, 12:27 PM
I also thought it could be a push propeller but could not find any info on that.




Many (but not all) pusher propellers were left hand thread. Yours is right hand.

chinaprop
02-25-2016, 02:09 PM
Hello Bob,

This drawing illustrates exactly your story above and size wise it is more likely. The strange thing is that only one Do x ever landed here on the way back from New York after the botched record attempt to cross the Atlantic.

Dbahnson
02-25-2016, 06:27 PM
Notice how those props are "stacked" but not "notched". I think what Bob was alluding to was that your prop looks as if the hubs are machined to fit together without doubling the thickness of the hub. Lots of US built props were constructed that way.

Also, notice in the picture that those are left hand props. Yours is right hand.

chinaprop
02-25-2016, 09:00 PM
Thanks for your feedback, so I need to search for another type. I send an email to the Dornier museum. If anyone is supposed to know they should but no reply yet...it is interesting where this search will lead me.

Bob Gardner
02-26-2016, 12:54 PM
Dave,

The Dornier Do X, which weighed I believe 56 tons, had twelve engines, six each of tractor and pusher props, mounted in six pods above the wing. So tractor and pusher propellers were used.

With kind regards,

Bob

Bob Gardner
02-26-2016, 12:59 PM
Dave said;
Notice how those props are "stacked" but not "notched". I think what Bob was alluding to was that your prop looks as if the hubs are machined to fit together without doubling the thickness of the hub. Lots of US built props were constructed that way.

Dave, I didn't mean that. I think this hub is flat and mated to a similar flat surface on the other hub.

With kind regards,

Bob

chinaprop
03-01-2016, 01:20 PM
Hello,

I got an email back from the Dornier museum in Germany. As we can not find markings in the hub area but considering the length it is quite certain this prop is from the Do-x. This would make it very rare indeed. We try to find a place that has another one to compare but that is not easy. The saga continues because if it is from the Do-x maybe there is a mention in the logbook about one of the props being swapped on Faial. They had plenty of props on it that could get damaged considering the long journey they made on their transatlantic journey. Sure they carried spares

chinaprop
03-21-2016, 06:05 PM
Having found some pictures that match my exact propeller it seems that it is from a Spanish build Dornier WAL Ultra which was piloted by Major Ramon Franco, brother of general Franco. He crashed on a Transatlantic flight near Flores and was rescued by British aircraft carrier Eagle who took the crew and damaged plane to Horta, Faial where it was repaired. It got new props and this one stayed on the island. This also explains why it does not have engine identification numbers in the hub. It was a one off, not one produced for regular engines.

Bob Gardner
03-22-2016, 02:54 PM
Congratulations on your research. If you would allow me to say so, you have done very well to discover so much so quickly. And your prop with its Azores history is a marvellous treasure!

With kind regards,

Bob

Bob Gardner
03-22-2016, 03:07 PM
For fellow forumites, I attach an article below that I have just copied from Google, which I think describes this aircraft.

Plus Ultra was a Dornier Do J flying boat which completed the first transatlantic flight between Spain and South America in January 1926 with a crew of Spanish aviators, that included Ramón Franco and Julio Ruiz de Alda Miqueleiz, Juan Manuel Duran and Pablo Rada.

The Plus Ultra departed from Palos de la Frontera, in Huelva, Spain on January 22 and arrived in Buenos Aires, Argentina on January 26. It stopped over at Gran Canaria, Cape Verde, Fernando de Noronha, Pernambuco (Recife), Rio de Janeiro and Montevideo. The 10,270 km (6,381 mi) journey was completed in 59 hours and 39 minutes. The plane was subsequently donated to the Argentine Navy and was used to deliver airmail. It is currently on display in a museum in the city of Luján, Buenos Aires Province, Argentina.

The flight of the Plus Ultra followed approximately the route taken, in 1922, by the Portuguese aviators Sacadura Cabral and Gago Coutinho, in the first Trans-Atlantic flight over the South Atlantic (from Lisbon, Portugal to Rio de Janeiro, Brazil).

chinaprop
03-23-2016, 12:29 PM
He did two flights...this is what we know of the 1929 one:

n 1929 he attempted another trans-Atlantic flight, this time crashing the airplane to the sea. The crew was rescued days later by an aircraft carrier of the British Royal Navy.

He ran out of fuel near Flores, was missing for almost a week and was picked up June 29, 1929. His damaged plane was taken aboard the HMS Eagle and here there are two stories...one says he was fixed in Horta and another one is that it was brought to Gibraltar. Still researching. What is interesting is that there were no numbers in the hub as to for which engine it was. As the WAL of Franco was specially prepped for the journey it is likely there was no need for a number as it was build specifically for the Hispano Souza engines he used.