Not quite.
Almost entirely. GE was assigned the Hermes as a SAM as part of that program. GE immediately replaced the German P IX engine with one of GE's own design running on alcohol and LOX or RFNA. GE launched exactly 6 missiles of this type through 1950 before the program was dropped. None of the GE missiles had some external guidance system in use. The results of those 6 launches were so poor, and Nike was at that point looking very promising, that the US Army didn't want to waste more time and resources with the A-1 series.
From what I can find, the vanes had to be jettisoned. They were used in conjunction with Rüse, a telemetry set used for guidance during the vertical stage of flight to keep the missile stable. The controls on the fins were locked during this period. At the cant over point where the missile turned to start heading towards the target, Rüse was discontinued and the fire control guidance system took over using the control surfaces on the fins. Having the graphite veins remain in place would just fight those controls and they were no longer needed. Worse, if they stayed in place and one or more moved since there was no longer positive control of them, they could send the missile badly off course.
These are amazing documents. Thanks again Moin for making these fantastic documents available to the forum !
I wish I had thought of it before but confusing Wasserfall and Hermes A1 is like confusing a Dolphin with an Ichthyosaur. The external shape is very similar, as they both operate in a similar way in the same medium, but the insides .... different. Any cutaway diagram labelled "Ichthyosaur / Dolphin" should be viewed with equal suspicion.
I thought it was P IX for ages.... I guess Waterfall Engine (Wasserfall Ofen) was sufficient so it never got a more official sounding designation.
As stated by Moin1900 Wasserfall was C2 in the original SAM design study. C1 was was a solid fuel option. Evidence for a C3 option is weaker but I'm still searching.
if you do get to White Sands or Huntsville, an interesting experiment would be to put a magnet on the outer skin and see if it sticks. Its possible they used aluminium for the airframes. The Peenemunde team certainly would have if they could get hold of it....
I agree on the question of screw threads
Well the one on the left is a variant of an early design discussed some in Die deutsche Luftfahrt Die Pfeilflügelentwicklung in Deutshcland bis 1945 by Han-Ulrich Meier. p 377-378
The other part of this equation is that the point source of the target will flicker (thus generating a signal with a frequency determined by the spin speed of the disc and the number of divisions) while the diffuse background will produce a direct-current voltage which (in an ideal world) can be filtered out and thereby ignored. In the real world it's a different matter, and reflections off of clouds, the water, and even the sun itself were often sufficiently "point source" to fool the early missiles into taking a different course (as, of course, are countermeasure flares).
This would be solved in the 60's by use of liquid nitrogen cooling the seeker, but the early first-generation ones didn't have that luxury installed yet. The seeker heads also didn't have anything close to the ability to bandpass only a narrow range of frequencies. That was the next big improvement that came in the early 80's.
Thank you for sharing.
Here:
The design was highly speculative obviously. There are no details about how the guidance and flight controls would have worked and the range and speed seem highly optimistic given the use of diglycol solid fuel. As we know with Rheintochter, Rheinmetall was unable to get the desired range, speed, and altitude out of that missile using the same solid fuel. This lack of something better as a solid fuel was a major shortcoming of German wartime SAM development.
What was stopping them?
Tube technology for one. Tubes don't do well with very fine frequency bands. They tend to leak and drift as they age, heat, and cool. There's also the space issue in AAMs. The circuits are simple enough on their own
OK, I get you now. If LRC circuits won't cut it and you have to use tubes... yeah.
Naval Air Museum at China Lake CA.
Added to bucket list.
But that doesn't translate into widespread use. In any case, the need here is for a bandpass filter with a very narrow range of specific frequencies for use in an expendable missile.
Interesting. Did you find any other evidence for the existence of an infrared detector cslled Kiel ? It seems an especially awful code name for an IR device, given Elac did so much work on these and their home was Kiel. Like calling the "Manhattan Project" the "Los Alamos project"
I thought that too. But the pressure is not always there. Before launch, the nitrogen gas is only in the high pressure sphere, which is separate from (though obviously attached to) the external skin. There is no gas pressure (above ambient) applied to the monocoque propellant tanks until the missile is committed to launch. So any rigidity gain from gas pressure in propellant tanks is not available during ground handling.
The skin of the Wasserfall was sufficiently strong enough, and fully rigid that the nitrogen gas really doesn't add anything in terms of structural strength. The big concern with respect to the fuel tanks the Germans had was getting all the fuel out of them as the Wasserfall maneuvered. Unlike the A-4 where this wasn't an issue as the missile went straight up (more or less), with the Wasserfall, it maneuvered into different flight positions.
On the Wasserfall, the tanks were designed with a front and rear cap with the sides being the skin of the missile. That skin was rigid on its own by the thickness of the material. That is, full or empty, the missile was structurally rigid.
The Kiel Z I/II was originally proposed as a Flak missile homer, according to Fritz Trenkle.Interesting. Did you find any other evidence for the existence of an infrared detector cslled Kiel ? It seems an especially awful code name for an IR device, given Elac did so much work on these and their home was Kiel. Like calling the "Manhattan Project" the "Los Alamos project"
In some of von Brauns early Flak proposals he describes and diagrams a thing called the Spanner Geraet. Apparently fitted to some night fighters for a while. But this is an IR image intensifier, with an IR spotlight, rather than passive IR detection. It was von Brauns first proposal for IR terminal homing of the Flak rocket that eventually became Wasserfall. Superceeded later by several teams working on slotted scanner PbS cell passive IR homing, including Dr Weiss team at Peenemunde under von Braun.
