The history of post-war rockets on base German WW-II "Wasserfall" missile propulsion

Norbert Brügge, Germany

1.  German "Wasserfall" anti-aircraft missile

2.  Soviet R-101 test vehicle

3.  U.S. Hermes-A1 test vehicle

4.  U.S. Hermes-A3 ballistic missile

5.  French EOLE ballistic missile

6.  Egyptian Al Kaher-1 missile

7.  U.S. Viking-I sounding rocket

8.  U.S. Viking-II sounding rocket

9.  Egyptian Al-Kaher-2 missile

 
 
 

 German "Wasserfall" anti-aircraft missile

Visol/SV-Stoff


In the first version of the Wasserfall anti-aircraft missile (W-1), the wings were longer and less swept than the later versions. Also, the four wings located at the rocket's mid-body were offset by 45 degrees from the tail fins. This was thought to aid in the prevention of aerodynamic shielding of the steering mechanisms by the wings of the tail fins, but later windtunnel tests proved this unnecessary. The second design, W-5, was slightly larger, and the wings were smaller and sharply swept back. The final version, the W-10, was similar to the W-5 except it was 27% smaller.
The guiding system consisted of a ground operator, who steered the Wasserfall missile to the target by use of a joystick by line-of-sight. The missile was gyroscopically controlled in roll, pitch and yaw, and could be controlled from the ground via radio link in azimuth and elevation. This was achieved by the four graphite rudders placed in the rocket exhaust at the slower starting speeds, and later by the four air rudders mounted on the tail once higher speeds were reached.
The first launch did take place on February 28, 1944 from the island "Oie", near Peenemünde. The missile did not reach supersonic speed on this first test, only reaching a height of about 7,000 meters, but the second launch reached a speed of 2,772 km/h in vertical flight. By July of the same year, seven more missiles had been fired, and by early January 1945 a further 17 had been launched. Out of the 25 fired, 24 had radio control, and of these, ten failed to operate properly.

The not implemented development of a new large common mixing head "Ofen" for the A-4 missile series C, found at least in a reduced dimension for the „Wasserfall “ anti-aircraft missile an application.
The new mixing head engine design, developed by Dr. Walter Thiel, was based on Visol (Vinyl Isobutyl Ether + Anilin) and SV-Stoff (10 % Sulfuric Acid + 90 % Nitric Acid). The hypergolic Visol/SV-Stoff mixture was forced into the combustion chamber by pressurizing the fuel tanks with nitrogen gas released from separate tank. Visol is a byproduct of the fuel-distillation (coal liquefaction). SV-Stoff "Salbei"was widely distributed in the explosives industry and available in sufficient quantity.
"Wasserfall"was to have to stand ready for launching at a moment's notice, and it would have to stay fueled for possibly months on end, the liquid Oxygen/Alcohol fuel system of the A-4 could not be used. Instead, Visol and SV-Stoff  were used hypergolically (automatic ignition when mixed). Pressurized nitrogen was used to force the fuels into the combustion chamber, with rupture discs being fitted between the nitrogen tanks and in the pipelines.
 

              


W-1                                                         W-5




               
 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*sec

nominal

-

78.47 1552 88.39 1748 2.022 40 0.0506 3.54
 

 Soviet R-101 test vehicle                   

            TG-02/AK-20 ?


One complete Wasserfall experimental airframe was found in Germany by the Soviet's. This airframe was master template, was tested for materials used in construction, and became the source for all dimensions for the Soviet experimental R-101 anti-aircraft missile. At beginning the R-101 used the engine S08.01, similar the German Wasserfall engine. After many tests and the subsequent changes on the vehicle also was used a modified engine Isayev R-101B.36000-0.

A resolution of 17 September 1948 envisioned two test series, consisting of 12 launches in Phase 1 and 18 in Phase 2. By November 1948 the first of the 12 phase 1 rockets arrived for static tests at the firing stands at Kapustin Yar. These were used to test the Russian materials substituted for the German originals, the modified control systems, and so on.

The first 12 phase 1 launches were conducted between 1 January and 1 March 1949. The first dual launch took place on 6 January 1949 (rocket numbers 7 and 8). Typical for the early launches, number 7 lost one exhaust vane in the first second of flight and went out of control. Number 8 experienced severe oscillations and finally lost all of its gas vanes. Experimental flight trials with varying equipment fits began with rocket number 11 (firing order thereafter, numbers 12, 13, 15, 16, 14, 18, 19, 17, 20, 21, 22). The first launches were vertical shots. Later 'dral' shots went quickly from the vertical to a horizontal course.These tests showed the need for a concentrated program to solve defects in the original stabilisation and radio guidance design. Four vanes were added as a result of the tests to provide pitch control. By the end of 1949, the 18 second-series R-101 missiles were ready for test. Phase 2 tests began in December 1949 and were completed in January 1950. These missiles had the revised aerodynamic control scheme, but a whole new set of problems were encountered due to the incompressibility of air at transonic and supersonic velocities. So much rework was required that the prototypes were redesignated according to the differing solutions to the problems encountered. On 17 August 1951 was cancelled the work on the R-101 surface-to-air missiles by resolution.


     
R-101

  

  U.S. Hermes-A1 test vehicle                           

           Visol/IRFNA ?


After several configurations for the Hermes-A1 surface-to-air missile had been studied, it was decided in 1946 to base the missile on the war-time German Wasserfall. This Hermes-A1 was redefined as a pure test vehicle for guidance and control systems. During 1947 and 1948, component flight testing took place on V-2s, but problems with the rocket engine delayed the launch of the first Hermes-A-1 (RV-A-5; CTV-G-5) until 1950. After two failures in May and September 1950, the first fully successful flight occurred on 2 February 1951, followed by two more tests in March and April that year. This concluded the flight test program of the CTV-G-5, which was formally redesignated as RV-A-5 in mid-1951.
The used propellant mixture is not known. Presumably were it Visol and IRFNA (IRFNA=Red Fuming Nitric Acid (94% Nitric Acid, 6% Dinitrogen Tetroxide)
 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec  
1 19.05.1950 80              
2 14.09.1950                
3 02.02.1951                
4 15.03.1951                
5 26.04.1951                


   


   



 

 U.S. Hermes-A3 ballistic missiles

Ethyl-Alcohol/LOX


In late 1947, the U.S. Army established preliminary characteristics for the Hermes-A3 program, calling for a liquid-fueled rocket-powered surface-to-surface missile. In early 1948, the designation SSM-G-8 was assigned, but the project progressed very slowly in the first years. This was mainly because of frequent changes in the requirements, which repeatedly necessitated a complete redesign of the projected XSSM-G-8 missile. However, the Hermes-A3 program accelerated somewhat in 1951, when it was split into the RV-A-8 Hermes-A3A interim test vehicle and the SSM-A-16 (SSM-G-16) Hermes-A3B operational missile.
The first flight attempt of an RV-A-8 failed in March 1953, but the second test succeeded in June that year. Until January 1954, a total of seven Hermes A-3As were launched, but only two flights were fully successful. Nevertheless, the RV-A-8's reliable (for its time) high-performace liquid-fueled rocket engine and its inertial guidance system significantly advanced the state-of-the-art in ballistic missile design. Although the Hermes A-3 program was reduced to a pure research effort in June 1953, six XSSM-A-16 Hermes-A3B missiles were launched between May and November 1954. However, only one of these (in October) was fully successful. The XSSM-A-16, originally designed as the prototype for the operational missile, was of similar design but slightly larger than the RV-A-8, and featured a further improved radio/inertial guidance system.


       
RV-A-8
  

 
        
XSSM-A-16

 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*sec
RTV-A-8 13.03.1953 80              
18.06.1953                
13.08.1953                
05.10.1953                
21.10.1953                
20.11.1953                
15.01.1954                
XSSM-A-16 11.05.1954 95              
20.07.1954                
26.08.1954                
21.09.1954                
19.10.1954                
16.11.1954                

 

French EOLE (EA-1952) ballistic missile

Ethyl-Alcohol/LOX


The French LRBA in 1946 created a ballistic missile project EA 1946. The rocket was named EOLE (Vehicle using Liquid Oxygen and petroleum Ether). The second static test in 1950 ended in the explosion of the test stand. It was suspected that the mixture petroleum ether/LOX could be hypergolic.
Petroleum-ether was therefore replaced by ethyl-alcohol in a new version of the EOLE rocket (EA 1951). The tank arrangement was also modified; now in tandem instead of concentrically.
Two flight tests took place in November 1952 from Hammaguir. Both ended in failure, the fin arrangement being destroyed at the time of crossing the sound barrier. The EOLE project was cancelled in december 1952.
The nominal launch mass of the rocket would be 3.42 tons of which 2.72 tons are propellants. It had 0.80 m in diameter and is 8 m long. It was therefore decided to launch lightened vehicles with a propellant capacity reduced to 40%. Thrusts higher than 90 kN were obtained.
There no information as to which engine had the EOLE rocket. But there is no doubt that the engine was from the German "Wasserfall" rocket. France had short post the war developed no own engine with a thrust of 90 kN.


             
     
  

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*sec
Project -  89.7  1648  108.4  1991 2.727  50  0.0545  5.4
Test vehicle -  89.7  1648  108.4  1991 1.090  20  0.0545  2.2

  

  Egyptian Al Kaher-1 missile

Ehtyl-Alcohol/LOX


In 1958, Gamal Abdel Nasser, started the missile development program. Egypt turned to unemployed German scientists and technicians to spearhead its missile efforts.
Although by the departure of the Germans in 1962 resulted in a loss of expertise, Egypt's missile program had already succeeded in developing prototypes. Thus in early 1962, Egypt's first missiles entered the prototype test phase, and in 1962 the government announced that it had successfully test-fired two differently missiles.
A small missile is the Al Kaher-1. It is believed to be a single stage, liquid fueled, unguided rocket, developed on base the French EOLE rocket design. It has a simple wrapped-sheet airframe, with conical nose, flared skirt and four fixed fins. The Al Kaher-1 is about 7.5 m long; the core diameter is 0.80 m; the conical engine bay is widened to ~1.2 m.  The Al Kaher-1 used either directly the engine from German "Wasserfall" missile or the French EOLE rocket. Propellants were Alcohol / LOX. First two missiles were fires at a desert range on July 21, 1962.
  

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*sec
nominal* - 90.0 1667 108.1 2010 1.89 35 0.0540 3.8
* estimated data



 

 

 U.S. Viking-I sounding rocket

Ehtyl-Alcohol/LOX


The Viking (RTV-N-12) was a single-stage sounding rocket, powered by a Reaction Motors XLR-10-RM2 liquid-fueled rocket engine. The combustion chamber of the engine is identical to the German Wasserfall engine. The Viking's fuel tanks were integral with the rocket's fuselage, saving a significant amount of weight. The rocket used four tailfins for stabilization and had a gimballed nozzle for active pitch/yaw control by the autopilot system. No two Vikings were exactly identical because the results of each firing would be used to implement improvements in the next vehicle. A total of seven Vikings of the original basic RTV-N-12 design were built and launched, and all flights were at least partially successful. The highest altitude was reached by Viking No.7 on 7 August 1951, which flew to 219 km. The scientific payloads carried by the RTV-N-12 included temperature, density and composition measurements in the upper atmosphere, measurements of solar and cosmic radiation, and ionospheric experiments.


    


    




Photo source: http://www.postwarv2.com/viking/sphotos/photos.html

 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*sec
1 03.05.1949 90.97 1617 110.3 1960 3.070 54.5 0.0563 6.0
2 06.09.1949 91.03 1421 113.1 1764 3.175 49.5 0.0641 5.6
3 09.02.1950 90.97 1488 111.9 1831 3.642 59.6 0.0611 6.7
4 11.05.1950 90.97 1855 107.6 2199 3.629 74 0.0490 8.0
5 21.11.1950 83.63 1789 89.9 2132 3.701 79 0.0468 7.9
6 11.12.1950 92.52 1761 110.5 2104 3.674 70 0.0525 7.7
7 07.08.1951 93.77 1873 110.0 2216 3.606 72 0.0501 8.0

 

 U.S Viking-II sounding rocket

Ehtyl-Alcohol/LOX


Viking rockets No.8 and later were of a significantly revised design, and were formally designated RTV-N-12A. Externally, the RTV-N-12a was slightly shorter than the RTV-N-12, had a much larger diameter, and used triangular fins. The new external shape allowed the carriage of more fuel without a penalty in empty weight. Another new feature were small jets to control the missile's attitude outside the atmosphere after main engine shutdown. The first RTV-N-12A, Viking No.8, was destroyed during a static engine test in June 1952, but Viking No.9 flew successfully in December that year. The highest altitude of any Viking was reached by No.11 on 24 May 1954 with 254 km. The last two Vikings (No.13/14) were used as test vehicles (with new propulsion) in the Vanguard satellite launch vehicle program.


  


   






    

Photo source: http://www.postwarv2.com/viking/sphotos/photos.html
 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec  MN*sec
8 06.06.1952 95.19 1416 118.2 1759 4.100 61 0.0672 7.2
9 15.12.1952 94.17 1809 111.9 2153 5.150 99 0.0520 11.1
10 07.05.1954 93.37 1802 111.1 2145 5.184 100 0.0518 11.1
11 24.05.1954 95.19 1863 112.8 2206 5.261 103 0.0511 11.6
12 04.02.1955 91.19 1795 108.5 2138 5.178 102 0.0508 11.1
13 08.12.1956 new engine GE X-405; new propellant Kerosene/LOX
14 01.05.1957

 

 Egyptian Al Kaher-2 ballistic missile

Ehtyl-Alcohol/LOX


In 1958, Gamal Abdel Nasser, started the missile development program. Egypt turned to unemployed German scientists and technicians to spearhead its missile efforts.
Although by the departure of the Germans in 1962 resulted in a loss of expertise, Egypt's missile program had already succeeded in developing prototypes. Thus in early 1962, Egypt's first missiles entered the prototype test phase, and in 1962 the government announced that it had successfully test-fired two differently missiles.
A larger missile is the Al Kaher-2. It is believed to be a single stage, liquid fueled, unguided rocket developed on base the U.S. Viking sounding rocket technology. It was about 12 m long and had a continuous diameter of about 1.2 m. Noticeable are delta-shaped fins, much like the at the US Viking.
The engine was taken either directly from the German "Wasserfall" missile or the French EOLE. Possibly it was an improved engine XLR-10-RM2 from the U.S. Viking sounding rocket (93 kN thrust). Propellants were Alcohol / LOX. First two missiles were fires at a desert range on July 21, 1962.



 

No.

Launch Thrust s.l. Isp s.l. Thrust vac Isp vac Propellant Burn time Flow rate Total Imp vac

-

- kN Ns/kg kN Ns/kg tons sec t/sec MN*s
nominal* - 93.0 1804  108.1 2099 4.90 95  0.0515 10.3

* estimated data