Project Kurt

[Hood]

I'm not sure where this would go so I'm posting here as a WW2 project.

Some time ago I thought I'd read either on the web or in a book about a German Wallis-type bouncing bomb project and a modified Fw190 that carried two of them. I never found the source again and I thought I was imagining things. However, last night I brought a DVD about the Dambusters raid and it showed a German offical film clip showing a Fw190 dropping two bouncing bombs on a test. This was codenamed Project Kurt. Now I know my mind was not playing tricks but I would like to know more.

What modifications were made to the Fw190?

How did it take-off? Surely the two bombs and the carrying booms would have made a conventional take-off very hard, so was it piggy-backed on a Ju88 like the Mistel?

How heavy were the bombs? To carry two they cannot have been as heavy as the smaller British Highball carried by the Mosquito.

Any questions and info most welcome.

 

[JC Carbonel]

As far as I know the film clip is all that remains of the project. However in the Purnells history of world war "german secret weapons" John Batchelor drew a variation of Kurt with the ball bomb being pushed by a rocket booster (similar to a light bulb in general appearance) and then a more complex variant has been found recently. see the discussion here :
http://www.luftwaffe-experten.org/forums/index.php?showtopic=1533

JCC

 

[smurf]

JCC your link won't let me in - error message

 

[PMN1]

I'm not sure what changes were made but from what I've read, the Admiralty were abit worried about the whole bouncing bomb thing as in their words 'we have more ships for them to be launched at'.

 

[JC Carbonel]

http://www.luftwaffe-experten.org/forums/

this link should be OK . then you have to proceed to "air launched/dropped bombs, torpedoes, rockets" then pick up the "Kurt" thread...

JCC

 

[smurf]

Thanks, JCC. I got there eventually!

 

[moin1900]

Hi everybody

I have heard that there was a bigger Version of the "Kurt"?
Is there anybody who knows more about that Project ?

Many greetings

 

[Grzesio]

I'm aware of four versions of the powered Kurt at the moment.
Two (modelled after line drawings) are illustrated at the LEMB forum linked above:
http://img.photobucket.com/albums/v432/Grzesio/SB800RS_comp.jpg
One is known from a popular photograph, looking pretty like the lower version in the drawing, but with just four instead of eight fins and w/o the nose cone.
The last version is included in the OP 1666 (I believe ) - it has a box fin an gyroscopic stabilisation.
Kurt was not very heavy - its warhead weighted just 385 kg (what is sometimes given as the weight of the whole bomb). It used a low pressure solid propellant booster with a reduction valve, typical for German rocket bombs (e.g. PC 1000 RS), ignited by an electric fuse a moment after release (charging head is visible on top of the body, between the suspension point and support frame).

Regards

Grzesio

 

[moin1900]

Hi everybody

To Grzesio: Thanks a lot! The information and Picture about the Kurt is very interesting!

Many thanks

 

[Vladimir]

Hi, did any one can post more info about it? Pictures , diagrams, drowings, etc.

Here is only what i have:

 

[Grzesio]

Two of the variants mentioned above.
The picture posted by you is redrawn from the OP-1666.

 

[Vladimir]

Oh cool, Grzesio! Have more? Have many version at all developed?

And for what that "cone" attached to "ball" at forward?

 

[Grzesio]

It's hard to say, how many variants were developed - available data are very sketchy and often conflicting.
Apparently there was an unpowered variant with gyroscopic stabilization, then powered variants with or without stabilization (box and X stabilizers can be observed); I think majority of changes between them considered the form of stabilizers itself.
Then there was the Kurt 2 project under development by RhB in 1944, but it went no further than windtunnel trials.

I think the cone was added for aerodynamic purposes - the bomb reached velocity of 330 m/s, also around Mach 1. This cone was present on the Kurt 2 study, but I'm not sure if the bomb pictured at the bottom is the Kurt 2 or some later Kurt variant (it has eight fins).
I also think now, the upper bomb shouldn't have a ring stabilizer - but the exact shape (box or X) is impossible to establish. Both these bombs do not have gyroscopes though.

 

[dogsbody]

A wee video:





Chris

 

[Jemiba]

For whatever it is worth, as I remembered, that we had this theme, and I just accidentally found this sequence of
stills, probably from the above mentioned film, here it is:
(From Brian Johnson, "Streng Geheim", English title "The Secret War", 1978)

 

[sienar]

Kurt I; Ricochet bomb dropped from low altitude by a Fw-190 or Fw-262(?). The conical cap was to reduce drag and it was jettisoned after release.

The spherical section contained HE wtih three fuzes, two of which were hydrostatic and could operate at up to 8m depth. The third fuze was a 25 second delay fuze in case the bomb became embedded in the target.

The rocket ignited 0.7 seconds after release and burned for 1.8 seconds. When released from a 190 @ 250m per second range was 2500m, when dropped form a 262 @ 300mps range was 3500m.

A gyro in the tail controlled the two ailerons in the tail to maintain the flight directoin.

Kurt II - modification of Kurt I with a longer tail. It had a slightly increased range and skipped flatter, leading to less influence by high seas.

 

[Scapaflow]

View attachment 694510

It's an annotated reconstruction in English. It probably comes from an allied report. A reference please.

 

[Graham1973]

As the video posted by dogsbody has disappeared I found another copy of the short clip showing the Kurt bouncing bomb under test on YouTube, sadly it's watermarked.

View: https://www.youtube.com/watch?v=J1JBYIClEd0

 

[publiusr]

Like an Enzmann ship with a warp ring