R-3A Conjectural

So much new technology was involved for the R-3 that it was deemed necessary to build an R-3A intermediate experimental rocket, based on the R-2. This would be flown to test new construction methods, guidance systems, and high energy propellants. The R-3A was specified in 1949 to have a 900 to 1000 km range with a payload of 1530 kg; an unfuelled mass of 4100 kg; 20,500 kg of propellants; and a lift-off thrust of 40 tonnes. The R-3A could also serve as a prototype for a more modest IRBM. Flight tests of the R-3A were scheduled for October 1951.

The R-3 itself was cancelled when difficulties were encountered in engine development and the decision was made to proceed directly to the R-7 ICBM. During its development the range of the R-3A had settled on 935 km with only a 500 kg payload. It was cancelled in October 1951 without ever flying, with the technology being applied to the R-5 and R-11 missiles. The Russians have been very reluctant to reveal the configuration of the R-3A. It seems likely that it was actually a subscale version of Groettrup's G-4 design, and formed the technical basis for both the R-7 ICBM and N1 super launch vehicle.

Manufacturer: Korolev. to a: 935 km range trajectory. Liftoff Thrust: 400.000 kN (89,920 lbf). Total Mass: 23,400 kg (51,500 lb). Standard warhead mass: 500 kg (1,100 lb). Maximum range: 900 km (550 mi).

• Stage Number: 1. 1 x Stage: R-3A. Gross Mass: 19,900 kg (43,800 lb). Empty Mass: 3,500 kg (7,700 lb). Thrust (vac): 434.400 kN (97,657 lbf). Isp: 235 sec. Burn time: 83 sec. Isp(sl): 210 sec. Diameter: 1.65 m (5.42 ft). Span: 3.50 m (11.40 ft). Length: 20.00 m (65.00 ft). Propellants: Lox/Alcohol. No Engines: 1. Engine: RD-102. Status: Development ended 1951. Further incremental upgrade of R-2. Payload 500 kg. Range 935 km. Developed from 1949 to October 1951. Cancelled, work combined with 8K14 development.

1949 December 7 - Launch Vehicle: G-4, R-3, R-3A, R-5, R-11, R-11FM, R-7, Buran, Burya.

• Groettrup G-4 IRBM evaluated against Korolev's R-3. R-3 project reformulated Nation: USSR. Program: Navaho. The NTS (Scientific-Technical Soviet) of NII-88 met in plenary session and subjected Korolev's proposal to withering criticism. The G-4 was found to be superior. After heated discussion, the Soviet approved further development of technology for the R-3, but not the missile itself. The decisions were: an R-3A technology demonstrator would be built and flown under Project N-1 (probably to prove G-4 concepts). Under Project N-2 both the RD-110 and D-2 engines would proceed into development test in order to prove Lox/Kerosene propellant technology. Packet rocket and lightweight structure research for use in an ICBM would continue under project N-3 / T-1. Winged intercontinental cruise missile studies would continue under project N-3 / T-2. Neither the G-4 or R-3 ended up in production, but the design concepts of the G-4 led directly to Korolev's R-7 ICBM (essentially a cluster of G-4's or R-3A's) and the N1 superbooster. Work on the G-4 continued through 1952.

• MOP decree authorised work to start on the R-5 and R-11. Nation: USSR. The R-3 3000 km range missile and R-3A subscale technology demonstrator were cancelled. As a replacement work was to start on the R-5 and R-11. The missiles originated as Theme N-2 of the R-3 project. This was an alternate approach to delivering nuclear warheads on West European targets - road-mobile or sub-launched missiles of shorter range with lighter warheads that could be launched from forward areas and reach enemy targets.

• Semenov, Yuri P Editor, Raketno-kosmicheskaya korporatsiya 'Energia' imeni S P Koroleva, Moscow, Russia, 1996. Russian in-house history of the Energia Corporation and its predecessors. Unprecedented detail, photographs, designations, and drawings, on the products of Korolev's OKB.

• Pervov, Mikhail, Raketnoye Oruzhiye RVSN, Violanta, Moscow, 1999.. Narrative overview of the missiles of the Russian strategic missile forces.

• Karpenko, A V, Utkin, A F and Popov,A D, Otechestvenniye strategischeskiye raketnoye kompleks, Sankt-Peterburg: Nevskii bastion; Gangut 1999.. Well-illustrated encyclopedia of the missiles of the Russian strategic missile forces.