N-1 Uni Soviet Rocket

The N1/L3 (from ??????-???????? Raketa-nositel', "Carrier Rocket"; Cyrillic: ?1)[4] was a super heavy-lift launch vehicle intended to deliver payloads beyond low Earth orbit. The N1 was the Soviet counterpart to the US Saturn V and was intended to enable crewed travel to the Moon and beyond,[5] with studies beginning as early as 1959.[6] Its first stage, Block A, remains the most powerful rocket stage ever flown.[7] However, all four first stages flown failed mid-flight because a lack of static test firings meant that plumbing issues and other adverse characteristics with the large cluster of thirty engines and its complex fuel and oxidizer feeder system were not revealed earlier in development.[8]

The N1-L3 version was designed to compete with the United States Apollo program to land a person on the Moon, using a similar lunar orbit rendezvous method. The basic N1 launch vehicle had three stages, which were to carry the L3 lunar payload into low Earth orbit with two cosmonauts. The L3 contained one stage for trans-lunar injection; another stage used for mid-course corrections, lunar orbit insertion, and the first part of the descent to the lunar surface; a single-pilot LK Lander spacecraft; and a two-pilot Soyuz 7K-LOK lunar orbital spacecraft for return to Earth.

The N1-L3 was underfunded and rushed, starting development in October 1965, almost four years after the Saturn V. The project was badly derailed by the death of its chief designer Sergei Korolev in 1966. Each of the four attempts to launch an N1 failed, with the second attempt resulting in the vehicle crashing back onto its launch pad shortly after liftoff. The N1 program was suspended in 1974, and officially canceled in 1976. All details of the Soviet crewed lunar programs were kept secret until the USSR was nearing collapse in 1989.[9]

N-1 Rocket History

In 1967 the United States and the Soviet Union were in a race to be first to land a human on the Moon. The N1/L3 program received formal approval in 1964, which required development of the N1 launch vehicle, comparable in size to the American Saturn V.

On Nov. 25, 1967, less than three weeks after the first Saturn V flight during the Apollo 4 mission, the Soviets rolled out an N1 mockup to the newly constructed launch pad 110R at the Baikonur Cosmodrome in Soviet Kazakhstan. This Facilities Systems Logistic Test and Training Vehicle, designated 1M1, was designed to give engineers valuable experience in the rollout, launch pad integration, and rollback activities, similar to the Saturn V Facilities Integration Vehicle SA-500F testing at the Kennedy Space Center in Florida in mid-1966. While the crawler transported the Saturn V to the pad vertically, the N1 made the trip horizontally and was then raised to the vertical position at the pad – a standard practice in the Soviet space program. On December 11, after completion of various tests, the N1 rocket was lowered and rolled back to the assembly building. The 1M1 mockup was used repeatedly in the following years for additional launchpad integration tests.

Although this test was carried out in secret, a US reconnaissance satellite photographed the N1 on the pad shortly before its rollback to the assembly building. NASA Administrator James Webb had access to this and other similar intelligence that showed that the Russians were seriously planning crewed lunar missions. That knowledge influenced several key US decisions in the coming months. The satellite imagery appeared to show the USSR was close to a flight test of the N1, but did not reveal that this particular rocket was just a mockup[a] and that the USSR was many months behind the US in the race to land a human on the Moon. The Soviets were hopeful that they could carry out a test flight of the N1 in the first half of 1968, but for a variety of technical reasons the attempt did not occur for more than a year.

a (though, at the very least, the CIA, the NRO, and President Lyndon Johnson did know that the rocket was a mockup per the 12-27-67 daily presidential briefing)
Early Soviet lunar concepts
Static 3D model of the rocket

In May 1961, the US announced the goal of landing a person on the Moon by 1970. During the same month, the On Reconsideration of the Plans for Space Vehicles in the Direction of Defense Purposes report set the first test launch of the N1 rocket for 1965. In June, Korolev was given a small amount of funding to start N1 development between 1961 and 1963. At the same time, Korolev proposed a lunar mission based on the new Soyuz spacecraft using an Earth orbit rendezvous profile. Several Soyuz rocket launches would be used to build up a complete Moon mission package, including one for the Soyuz spacecraft, another for the lunar lander, and a few with cislunar engines and fuel. This approach, driven by the limited capacity of the Soyuz rocket, meant that a rapid launch rate would be required to assemble the complex before any of the components ran out of consumables on-orbit. Korolev subsequently proposed that the N1 be enlarged to allow a single launch lunar landing. In November-December 1961, Korolev and others tried to further argue that a super heavy lift rocket could deliver ultra heavy nuclear weapons, such as the just tested Tsar Bomba, or many warheads (up to 17) as further justification for the N1 design.[10][11] Korolev was not inclined to use the rocket for military uses, but wanted to fulfill his space ambitions and saw military support as vital. The military response was lukewarm – they thought the N1 had little military usefulness and was worried it would divert funds away from pure military uses. Korolev's correspondence with military leaders continued until February 1962 with little progress.

Meanwhile, Chelomei's OKB-52 proposed an alternate mission with much lower risk. Instead of a crewed landing, Chelomei proposed a series of circumlunar missions to beat the US to the vicinity of the Moon. He also proposed a new booster for the mission, clustering three of his existing UR-200s (known as the SS-10 in the west) to produce a single larger booster, the UR-500. These plans were dropped when Glushko offered Chelomei the RD-270, which allowed the construction of the UR-500 in a much simpler "monoblock" design. He also proposed adapting an existing spacecraft design for the circumlunar mission, the single-cosmonaut LK-1. Chelomei felt that improvements in early UR-500/LK-1 missions would allow the spacecraft to be adapted for two cosmonauts.

The Strategic Missile Forces of the Soviet military was reluctant to support a politically motivated project with little military utility, but both Korolev and Chelomei pushed for a lunar mission. Between 1961 and 1964, Chelomei's less aggressive proposal was accepted, and development of his UR-500 and the LK-1 were given a relatively high priority