What is the N1 rocket Russians used?

The N1 rocket, officially known as the UR-700, was a super heavy-lift launch vehicle developed by the Soviet Union in the 1960s and early 1970s. It was designed to launch the Soviet LK lander and other payloads to the Moon as part of the crewed lunar landing program, designated as the Soviet lunar programme.

Development of the N1 began in 1959 under the leadership of Sergei Korolev, the chief designer of the Soviet space program. The rocket was designed to be capable of launching payloads of up to 95 tons to low Earth orbit, with an initial goal of landing a Soviet cosmonaut on the moon by 1970.

The N1 was a massive and complex rocket, standing at 105 meters (344 ft) tall and weighing over 2,700 tons (5.9 million pounds) at liftoff. It had four stages, each powered by a cluster of powerful rocket engines. The first stage, known as the Block A, consisted of 30 NK-15 engines and generated 45.4 MN (4,627,000 lbf) of thrust. The second stage, known as the Block B, had eight NK-15 engines and generated 11.2 MN (1,145,000 lbf) of thrust. The third stage, known as the Block V, had four NK-21 engines and generated 4.56 MN (465,000 lbf) of thrust. The fourth and final stage, known as the Block G, had a single NK-19 engine and generated 1.57 MN (160,000 lbf) of thrust.

Despite the ambitious nature of the project and significant resources dedicated to its development, the N1 program encountered numerous challenges and setbacks. The rocket suffered from a series of design flaws and technical issues, including problems with engine reliability, fuel leaks, and structural failures. Four attempted launches of the N1 rocket between 1969 and 1972 all ended in failures, with the rockets experiencing explosions or malfunctioning shortly after liftoff.

Due to the persistent failures and the growing costs associated with the program, the Soviet government eventually decided to cancel the N1 project in 1974. The decision marked a significant setback for the Soviet space program and put an end to their ambitions of achieving a crewed lunar landing ahead of the United States.

Despite its ultimate failure, the N1 rocket represented a significant milestone in Soviet space technology and contributed to the development of future Soviet launch vehicles, including the Proton rocket and the Energia rocket. The lessons learned from the N1 program also influenced the development of space launch systems in other countries, including the United States.