Roden 1/72 PKZ-2. Austro-hungarian helicopter 1918.

[Profa]

Well, this would be my first post here...
After some WWII projects finished, I decided to turn back to my true love - WWI miracles... Currently I'm talking about first working chopper, built in KuK in 1918. Unfortunately it didn't go beyond trial flights, but nonetheless was very interesting subject to build:


Mid-build pics:


Here it is beside reference object:


I also intend to make wooden platform for it, but it has to wait until my daughter eats suitable number of ice-creams...

Well, your comments and critics are mostly welcome... I'm going to be brave and stand the fire...

[Varese2002]

Impressive build quality Profa . I am now at work and cannot check details etc. but the machine looks very authentic (no spurious crosses etc. as on the outside of the Roden box in the artist impression).

It is not your problem, but I hate the spurious designation P-K-Z (Petroczy-Karman-Zurovec) which surely is not to be seen in contemporary documents. Both Petroczy and Karman had no work at all in this machine. All project leading and overall design was done by Wilhelm Zurovec, who still in this late day must get the full honour for this machine.

I will come back in the evening, when I have my documents at hand.

Cheers

Kees

[Profa]

Originally Posted by Varese2002

I am now at work and cannot check details etc. but the machine looks very authentic (no spurious crosses etc. as on the outside of the Roden box in the artist impression).

Yep, I've made it as it was 90% of trial flights - without observer's cupola. Maybe eventually it'll get cupola (together with the platform), but again without never-used crosses

Originally Posted by Varese2002

It is not your problem, but I hate the spurious designation P-K-Z (Petroczy-Karman-Zurovec) which surely is not to be seen in contemporary documents. Both Petroczy and Karman had no work at all in this machine. All project leading and overall design was done by Wilhelm Zurovec, who still in this late day must get the full honour for this machine.

Only available book regarding this aircraft (at least to me) is Windsock's Mini-datafile No.2, and there I've seen the same info regarding inventor, Lt. Wilhelm Zurovec (could be seen here in the cupola: Petroczy-Karman-Zurovec PKZ 2 helicopter - development history, photos, technical data). I believe the name was given after PKZ-1, where everybody mentioned took some part of work...

Thanks anyway!

Cheers,
Zoran

[Sreiko]

Great work Profo and must say that you are direct hit into the Kees sphere of interest! Very good work and I also like that less know subjects.

Keep on good work

[Varese2002]

I studied on your Roden model and found a small inconsistency, which I have tried to explain in a picture.


[enlargement via Webshots - click on the picture above]

Your machine is clearly the original version of the Žurovec machine. This version can be distinguished by the form of the small cushions at the end of the three feet, which are completely (or almost) round.

The machine was modified (stronger radial engines), which differed by another form of cushion and the use of Bosch starters for the engines.

Your model is a mix from the original version and the amended version, as the cushions are from the original and clearly between the bays can be seen the Bosch starters.

As already said Vilem Žurovec (to give him his Czech name) did all the work on this machine, which was contemporary designated S.F. Flugzeug mit Benzinantrieb, where S.F stands for Schrauben Fessel or Schrauben Flieger.

I enclose an interesting archive piece, giving the people that were present at the offical presentation of the S.F. Flugzeug mit Benzinmotor on June 10, 1918. The last sentence gives that as a guest Oblt. Prof. Dr. Theodor von Kármán was present.

Already in articles in 1921 / 1922 the ebullient Professor Kármán claimed in writing that he almost did it all, with a little work from Petroczy and Žurovec. His published memoirs were - regarding this Schraubenflieger - almost equally egocentric.

Cheers

Kees

[Profa]

Well, thanks for this enlightement, Kees

This cushion feature is really hardly noticeable, and needs attention you drew... On this drawing, taken from the book I've mentioned, could be seen that cushions are, as you said, almost round, while Bosch starters are present as well . Also mentioned are 120HP Le Rhones...:

Obviously Roden leaned on this info while preparing the moulds

To be honest, I took much more attention to engine detailing and rigging than to this matter...
I'm not such an expert in these "small but important" details, but that's why I'm here - willing to learn
Thanks again!