Fw 190 VDM propeller blade types

[Roger Gaemperle]

Hello,

Does anybody know where I could find information about the different propller blade types used on the Fw 190?

As far as I could find out, the following types were used:

VDM 9-12067 A : metal
VDM 9-12153 A : metal with external pitch weights
VDM 9-12176 A : wooden

I am trying to find out:
- What were the differences (further to the ones mentioned above)?
- What was the sequence when they were introduced?
- The VDM 9-12153A appears to have not seen wide use. Was it superseded by the wooden blade soon after its introduction?

Thanks,
Roger

[S Sheflin]

Roger,

I am glad someone finally asked this most interesting FW 190 prop question. I too have long wondered the reason for the metal Fw 190 propeller blades with counterweights.

I can’t recall where, but in the dim recesses of my age-addled mind I recall reading somewhere that the weights were added as nose ballast to compensate when one of the engine boost systems (MW50 or GM-1) were added to the Fw 190. Can anyone confirm or refute his for us?

Steve Sheflin

[Roger Gaemperle]

Steve,

Thanks for your reply. I guess only the original manuals could explain the differences. I was not able to locate them, unfortunately.

When looking for an explanation I found the following paragraph:

"The first attempts at constant-speed propellers were called counterweight propellers which were driven by mechanisms which operated on centrifugal force. A counterbalance was set up near or in the spinner, held in by a spring. When the propeller reached a certain RPM, centrifugal force would cause these counterbalances to swing outwards, which would drive a mechanism that twisted the propeller into a steeper pitch. When the airplane slowed down, the RPM would decrease enough for the spring to push the counterweights back in, realigning the propeller to the shallower pitch."

So it appears to be related to the constant speed propeller? But how was this solved with the earlier metall type propeller and with the large wooden propeller?

Maybe there is an airplane mechanic / propeller engineer in the forum who could help?

Thanks,
Roger

[badatflyski]

propeller with weights were used on Antons A8-9(with 801D) equipped with fuselage fueltank. it was done to compensate the CG (like moving the ETC 15cm forward), the A8 field-moded without the rear tank didn't have this prop and also didn't have the ETC.

Those weights have nothing to do with the constant speed, as the the prop was comanded by a hydraulical mecanism by the kommandogerrat with an electric back-up for manual pitch control to be used by the pilot in case of a defect in the constant speed mecanism or the kommandogerrat.

ps: sorry for my poor english.

[Roger Gaemperle]

Hi Badatflyski,

Thaks for your message. May I ask you for the source of your information? If I understood you correctly:

The propeller weights were added if the fuselage fueltank was installed, but not the ETC (which would have been moved forward)?

Or did you mean that the weights were an additional measure together with the moved forward ETC if the fuselage fueltank was installed?

It appears to me a rather complex solution to add weight to rotating parts (to offset the CG shift due to the fuselage tank). Wouldn't it have been easier to add it somewhere in the engine compartment or e.g. increase front armor thickness? Or is there yet another reason why these weights were added?

Regards,
Roger

[ClinA-78]

Hello gents,

For your interest, a picture showing a counterweight coming from FW 190 A-8 WNr. 170116. As a matter of facts, only A-7, A-8, A-9 seems to have been equipped with that device.
Best regards.

ClinA-78

[Pawel Burchard]

Great photo, thanks. Is 9-12153.51 the part number for the weights?

p.

[badatflyski]

Originally Posted by Roger Gaemperle

Hi Badatflyski,

Or did you mean that the weights were an additional measure together with the moved forward ETC if the fuselage fueltank was installed?

Yes, that's it.

The source of this info is White1fundation.
The Antons with rear fuselage had always an ETC (moved 15cm forward, from memory)

I find it also a strange solution for a CoG compensation. Will check for pictures of A8/R versions, those were normally equipped with a bigger(heavier) oiltank armor, will be interesting to see if on this version the weights are also present.

[ClinA-78]

Hello,

Pawel, I presume this is the part number (cf Roger's first input), but don't know what is the meaning of '.51';
However I have noticed also a Ju 88 R-2 equipped with counterweight, so would it be also a matter of particular engine, not only related to ETC and 'boosting' system? Never seen a counterweight on woodden blade from a Jumo 213 for instance, why?

Best regards

ClinA-78

[Milos Gazdic]

Very interesting discussion guys!

Does any one know what was the difference in weight between three types of props: VDM 9-12067 A, VDM 9-12153 A & VDM 9-12176 A?

Were there any 190s with the additional tank added still using wooden props?