Bf-109 wooden propellers?

[SPEKTRE76]

I saw a picture online of a restored Bf-109 and upon closer inspection I noticed wood grain under the paint? I saw a video on YouTube 'Luftwaffe's Deadliest Mission' and they talked about how the 109 and the Fw-190 were used for ramming. I heard "the Me-109's steel propeller cut through....". Was that an upgrade for that type of mission or did the museum restoration crew improvise?

 

[Crimea_River]

Early war props were steel. Late war props tended to be wood to save on strategic materials.

 

[nuuumannn]

Early war props were steel

I suspect they were aluminium, not steel.

 

[Crimea_River]

My bad. I believe you are correct.

 

[GrauGeist]

As far as "ramming" goes, Bulgarian pilots were known to intentionally ram Allied bombers unlike the German pilots...

 

[meatloaf109]

Someone with some aero-engineering could probably enlighten us, but I believe that the laminated wood props saved on structural or engine mount damage in the event of a wheels up landing.

 

[rochie]

got a pic of a wooden prop blade from an Fw190 that i took while in the Czech Republic i'll find it and post it over the weekend

 

[stona]

The earliest two bladed propellers on the early Jumo powered Bf 109s were wooden but were replaced by a two bladed,variable pitch,metal propeller.
Later models all had metal propellers (by VDM).
I'm not 100% sure about the broad bladed props fitted to some late war versions and can't check at the moment. Nonetheless almost all WW2 era propellers fitted to the Bf 109s were metal.

The "paddle" bladed props fitted to the Fw 190s were indeed a laminated,coated,wooden construction.

Steve

 

[FLYBOYJ]

Someone with some aero-engineering could probably enlighten us, but I believe that the laminated wood props saved on structural or engine mount damage in the event of a wheels up landing.

They did not. For the most part any prop strike be it from a wood or metal prop will, at a bare minimum will have the potential to cause internal engine damage. Depending on the severity of the prop strike and the design of the mounting system will more than likely determine if motor mounts will have to be changed. The manufacturer will sometimes have requirements in their maintenance manuals regarding prop strikes.

 

[meatloaf109]

I learn something new every day, Thanks!

 

[unix_nerd]

Hallo all,

Yes, I agree. After a prop strike or wheels up landing with broken blades an indeep engine inspection is needed.
Bf019 were fitted with metall and wood props. The Spitfire used wood blades as well - a modified wood called "Jablo" (?)
And yes only the blades were made of wood - not the hub. This part was highly stressed and only metall (steel) could withstand the forces.
Best regards

 

[unix_nerd]

Hallo all,

Yes, I agree. After a prop strike or wheels up landing with broken blades an indeep engine inspection is needed.
Bf019 were fitted with metall and wood props. The Spitfire used wood blades as well - a modified wood called "Jablo" (?)
And yes only the blades were made of wood - not the hub. This part was highly stressed and only metall (steel) could withstand the forces.
Best regards

 

[unix_nerd]

Hallo all,

Yes, I agree. After a prop strike or wheels up landing with broken blades an indeep engine inspection is needed.
Bf109 were fitted with metall and wood props. So far I remember later versions had wooden blades as well. I 've seen on in am museum - these were really thick and wide for altitude performance I guess.
The Spitfire used wood blades too - a modified wood called "Jablo" (?)
And yes only the blades were made of wood - not the hub. This part was highly stressed and only metall (steel) could withstand the forces.
Best regards

 

[stona]

Jablo was the name of a company as well as a process. Jablo Propellers Ltd was founded by a Mr Jablonski, a Polish Jew who came to Britain in 1930. He was awarded the then substantial sum of £15,000 pounds by a Royal Commission after the war for his invention of 'a plastic wood which replaced metal propellers and enabled the Government to divert much needed metal to other purposes'.

The second company to produce wooden blades was The Airscrew Company Ltd with their 'Weybridge Blades'.

The third company to produce wooden blades was Hordern Richmond Ltd of Buckinghamshire. Their blades were known as 'Hydulignum - high duty wood material' blades.

Rotol bought blanks, not finished blades, and machined them themselves. The blades were covered with a material called 'Rotoloid' which, given the name, was a Rotol product.
Rotol was a company established by ROlls Royce and BrisTOL specifically to develop propellers for their aero engines.

Bruno Jablonski (who died in 1978 ) had worked in the German aircraft industry before seeing the writing on the wall. I don't know whether he had any input into the German wooden propeller blades.

I have plans of the three different British composite blades constructions which I will post when I have a better connection and if I remember. They are surprisingly different.

It is often ignored that the spinners fitted to Spitfires and Hurricanes are derived from a design, built under licence in the UK, from VDM in Germany!

Cheers

Steve

 

[stona]

Steve

 

[tomo pauk]

Great stuff, Steve

 

[gumbyk]

They did not. For the most part any prop strike be it from a wood or metal prop will, at a bare minimum will have the potential to cause internal engine damage. Depending on the severity of the prop strike and the design of the mounting system will more than likely determine if motor mounts will have to be changed. The manufacturer will sometimes have requirements in their maintenance manuals regarding prop strikes.

Either Lycoming or Continental (I can't remember which off the top of my head) define a prop strike as the propeller coming into contact with anything sufficient to slow the propeller down (water, long grass, etc).

However, the Yak 52 can have a significant amount cut off the blade (3-4 inches, AFAIK) following a prop strike, to enable a ferry flight.


Wooden blades do have a number of advantages over aluminium or steel blades - lighter, so less gyroscopic forces, better fatigue resistance, better damage tolerance.