Credit: © Mark Wade
Status: Cancelled 1951. Payload: 300 kg (660 lb). Thrust: 78.40 kN (17,625 lbf). Gross mass: 3,600 kg (7,900 lb). Height: 7.80 m (25.50 ft). Span: 2.34 m (7.67 ft). Apogee: 10 km (6 mi).
Stalin had determined to transfer German rocket technology to the Soviet Union with all possible speed. Following post-war assessments of German technology, it was decided, as a first step, to duplicate the full technical documentation of the German V-2 surface-to-surface missile and the Wasserfall, Rheintochter, and Schmetterling surface-to-air missiles. Decree 1017-419 of 13 May 1946 created the institute NII-88 at Podlipki, northeast of Moscow, for this work. SKB Number 4 was created within NII-88 in September 1946 for the purpose of developing the Russian copy of the Wasserfall, designated R-101.
The task facing the Russian engineers was formidable. Soviet teams in occupied Germany were only able to obtain incomplete technical documentation of the missile. There were no complete examples of the rocket to use as a starting point. The teams had recovered some German guidance equipment used during flight tests. For the warhead, there was only incomplete technical data related to test rockets. There was no information on the proximity fuse. The only information on guidance system hydraulics was a single example of an actuator from the missile. There was nothing available at all on the exhaust vanes used to vector the missiles thrust; nothing on the guidance; nothing on the antennae of the radio-command system.
One complete Wasserfall experimental airframe was found in Germany. This airframe was called the Obmerochniy, or master template, was tested for materials used in construction, and became the source for all dimensions for the R-101. The Obmerochniy was equipped with a complete guidance system, but this included the Messina telemetry system, and the Russian engineers had difficulty in telling what aspects of the missiles' avionics were intended for production and which were just used during tests. From elsewhere a 'Max' homing system and proximity fuse were later obtained.
The Russians were able to reconstruct the missile based only on these recovered items. The resulting draft project was defended before a plenary session of NII-88 on 5 June 1947. Yevgeniy Vasilyevich Sinilshchikov was the chief designer, V A Govyadinov the lead guidance engineer. The drawing package for the R-101 was completed by the end of 1947. This would be used in the first build of 50 test missiles. Four experimental areas, two test stands, and six labs were created for development and test of the missile's avionics, radio, guidance, telemetry, and performance measurement systems. Two stands were dedicated to propulsion tests, and one to the electrical system. NII-88 developed the mixed hydraulic/pneumatic control system, which required substantial development using these test stands. Thirty test launches of the R-101 were planned.
German specialists assisted the Russians in transferring the technology to the Soviet Union. The initial theoretical work on the technology for the R-101 was conducted at the 'Berlin' Institute under Engineer-Colonel Pokrovskiy, who supervised the work of Dr Klaus and other German scientists. At NII-88 Sadovskiy supervised the work of the German specialists from the end of 1944 at Section B1, redesignated Section 4 in February 1947. The R-101 used the S08.01 engine, which was built by German Wasserfall rocket engineers at Section 8 under the supervision of N L Umanskiy. It was pressure-fed using nitrogen gas stored in bottles at 250 atmospheres. Other subcontractors included NII-49 for the analogue computer; NII-504 for the proximity fuse; NII-885 MPSS for the radio beam guidance head; Factory 528 for the self-homing guidance head; Factory 523 for the exhaust vanes; NII-20 MU for the radio-straddling sight; NII-627 for the batteries, and GKS KB MM and P for the support equipment. An SU-152 artillery trailer was modified to carry the missile.
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 decree required that tests begin in 1949. Launch preparations began in December 1948 and 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 stabilization and radio guidance design. Four vanes were added as a result of the tests to provide pitch control. Sinilshchikov hit on a solution to the control difficulties, using four gap limiters, with guidance by horizontal control and course, by modulating the channel of roll. Further flight tests were delayed until these fixes were made. 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. These redesigns were the R-101A, R-101B (reformulated technical project, using a new R-101B.36000-0 Isayev 8.5 metric ton thrust engine), and R-101V. But problems identified in flight tests led to even this planned development schedule breaking down. The changes became so numerous that the airframes being produced, each with different modifications, were simply designated R-101E (experimental).
Meanwhile the Soviet leadership was casting a critical eye on surface-to-air missile work at NII-88. Korolev's ballistic missile work at SKB 3 was successful, but the work at the other SKB's on surface-to-air missiles was painfully slow in the face of a mounting US bomber threat. A review showed that every single surface-to-air missile project was behind schedule. The basic problem seemed to be that the artillery officers supervising the project were trying to build surface-to-air missiles using army artillery standards (e.g. emphasis on accuracy and dispersion at specified range). The other problem was the slow progress on surface-to-air missile guidance, which was well behind IRBM guidance development. This was unsurprising, since surface-to-air missile guidance dealt with a much more complex problem - how to hit a maneuvering, moving target?
On 16 June 1950 NII-88 was reorganized, with the previous SKB's being made part of either OKB-1 (surface-to-surface missiles) or OKB-2 (surface-to-air missiles). Korolev wanted to put Mishin in charge of surface-to-air missiles and talked to Ustinov about this possibility at a meeting at Kapustin Yar. This recommendation was not accepted, and Lev Robertovich Gonor was made the new deputy director in charge of all surface-to-air missile projects. He was quickly replaced by Konstantin Nikolayevich Rudnev. Isayev was named to head Section 9 of OKB-2, dedicated to rocket engine development.
Testing to that date of German-derived rockets by German specialists revealed that they had not in fact solved the surface-to-air missile guidance problem by war's end. Following a review by the new management of the ongoing projects, the inescapable conclusion was that a clean sheet of paper was needed in order to achieve a successful surface-to-air missile system. Therefore on 17 August 1951 resolution 3017-1118 cancelled work on the R-101 and R-102 surface-to-air missiles. Despite German assistance, the Wasserfall could not be developed into a viable weapon. Nevertheless much basic technology necessary for a successful surface to air missile design was acquired in the process of struggling with the R-101's problems.
In September 1951 further surface-to-air missile development was taken away from the army's artillery officers at NII-88 and transferred to Lavochkin's OKB-301 within MAP (the ministry in charge of Air Force hardware development). The R-101 test stands and project workers were transferred to OKB-301. Of six completed R-101E rockets and guidance systems, one R-101E airframe was sent to section 14 NII-88 for static and dynamic tests; four were sent to Section 2 of Factory 88. The launchers were moved to OKB-301 Section 2 for use in future development. The wiring harnesses were moved from NII-885 to OKB-301. Of 250 engineers and technicians working on the R-101 and R-102 at OKB-2, 57 moved to OKB-301, where Lavochkin had put G N Babakin in charge of future surface-to-air missile development. Babakin's office also received four engineers from KB-1 MV, five from Factory 586, two from MV Apparat, and five from other organizations, a total of 90 in all. Some NII-88 engineers were not transferred to the new organization due to their Jewish backgrounds. Isayev and Kostin remained within NII-88 but received 100 rocket engines from OKB-1. By 26 March 1952 there were two engine OKB's in NII-88, OKB-2 headed by Isayev, and OKB-3 headed by Sevruk. Both developed engines for surface-to-air missiles in parallel. Isayev's designs were the more successful, and in 1958 OKB-3 was closed and its workers and facilities taken over by Isayev. In January 1959 Isayev separated from NII-88 and became the independent OKB-2 under GKOT.
Maximum range: 25 km (15 mi). Boost Propulsion: Storable liquid rocket, 2022 kg propellant. Maximum speed: 800 kph (490 mph).