Vostok and GR-1 Credit - © Mark Wade

Korolev's entry in the 'Global Rocket' competition, a missile that could place a nuclear warhead in orbit, where it could come in under or behind American anti-ballistic missile defences, and be deorbited with little warning. Cancelled in 1964 in preference to Yangel's R-36-O.

The Global Rocket 1 (GR-1) requirement of 1961 called for a system to place a large 1,500 kg nuclear warhead equipped with a deorbit rocket stage into a low earth orbit of 150 km altitude. The warhead could approach the United States from any direction, below missile tracking radar, so little warning was available. Not only could such a missile hit any point on earth, but the enemy would also be uncertain when it would be deorbited onto target. The main disadvantage was lower accuracy of the warhead in comparison to an ICBM.

Korolev insisted on sticking to the liquid oxygen/kerosene propellants of his R-9 ICBM, despite the military's preference for the more toxic but storable propellants used by the other designers. In competition with Korolev's 8K713 design, Chelomei proposed his UR-200, while Yangel offered the R-36. Korolev considered the 8K713 a low risk project, using rocket elements already in development by his bureau:

• First stage: a stretched version of the first stage of the planned R-9M missile with Kuznetsov NK-9 engines
• Second stage: an adaptation of the Soyuz launch vehicle third stage
• Third stage: a development of the Molniya launch vehicle’s fourth stage with the S1-5400 engine.
• Missile sized for launch from existing R-9 launch silos

Cancellation of the 8K713 in March 1964 had a significant and perhaps fatal impact on the project for Korolev’s N1 moon rocket. Korolev had hoped that the GR-1 could be used to prove N1 engines concepts. This is remarked on in the editor's note to Korolev's letter to Khrushchev of 17 March 1964 ('Document written to N S Khrushchev on the path for development and experimental launch of the intercontinental global rocke GR-1'). Vetrov states:

S P Korolev also did not agree to cancellation of the GR-1, which had great potential for support of the future work of OKB-1. It was important to continue tests of the GR-1 in order to provide realistic tests for design ideas used in the rocket engines, that were analogous between the GR-1 and N-1. This was in accordance with an earlier communicaton between Korolev and Brezhnev (a letter written in 1959 at the beginning of the N1 program). Finally the only real test of the engines of OKB-276, developed according to aviation practices, came with the first flight tests of the N-1.

11A513. ASCC Reporting Name: Scrag. Article Number: 11A513. Complex: 11A513.

FOBS version. Warhead accuracy 5 km along orbital track, 3 km to either side. OKB-1 estimated warhead would be detected by Western defences only two minutes before it detonated. The designation SS-10 was assigned by the DOD to the UR-200, but was commonly and erroneously applied to the GR-1, which was shown publicly after its cancellation.