N1 (rocket)

The Nositel 1, short- N1 ( GRAU index 11A52 ) was a Soviet rocket that was developed as part of the Soviet manned lunar program.

Starting position

After the early successes of the Soviet space and the Soviet Union ran the " race to the moon " against the United States. While there all the resources were concentrated on the Saturn rocket for the Apollo program, two teams worked in the USSR in parallel to new missile projects. One of them was the OKB -1 ( RKK Energia today ) that developed the N1 moon rocket in 1959 under the direction of Sergei Korolev. However, the original design of Korolev saw the military use in the foreground. In the context of the early 1960s by the Soviet Union planned use of the cosmos for military objectives (Government Decree 715-296 of June 23, 1960) was from him the N1, as carrier for heavy reconnaissance satellites, defensive military payloads and as offensive support means for strikes against any point on earth offered.

One problem proved to be the development of the necessary powerful rocket engines. The former partner for engine development and Korolev's OKB -1, the OKB- 456 of Valentin Petrovich Glushko, now working closely with the competing design bureau OKB -52 of Vladimir Tschelomei. Korolev and Glushko had (single -versus four-chamber engine ) and fuel combination to be used hopelessly divided among other things on the engine design ( RP-1/Sauerstoff against UDMH / dinitrogen tetroxide ). Korolev therefore cooperated with the OKB -276 by ​​Nikolai Kuznetsov, which so far mainly jet engines and propeller turbines - had developed among the world's largest turbine engine NK -12 with about 11,000 kW ( 15,000 hp). Due to the hitherto lack of experience with rocket engines started to develop engines with large delays.

Technology

The N1 was at 105 m altitude, the largest ever built Soviet rocket and comparable in size and mass to the Saturn V. Due to the low thrust of the engines used NK -15 by Kuznetsov ( per 1,544 MN vacuum thrust) had in the first stage a large number of these engines are used bundled. Thus, the N1 should bring in their planned by Korolev original version with 24 engines in the first stage a payload of about 75 tons in the low earth orbit (English Low Earth Orbit or LEO ). With a single start, however, so that was not a manned mission to fly with the moon. Mishin has therefore introduced after the death of Korolev as a new project the draft six engines NK - 15 in the central section added. To further increase the payload he introduced a cooling of the kerosene in the tanks and modified the orbital parameters easily. Thus payloads now would have been possible in the LEO maximum of 90 to 95 t. The N1 was the engine assembly and the associated fuel and control systems, however, highly complex and proved to be very susceptible to interference. The total of 30 engines of the first stage were arranged in an outer ring with 24 engines ( the original design of Korolev ) and an inner ring with six engines ( by Mishin added). It was carried out the air between the outer and inner rings engine, this was for a type of aero engines inner spike effect with higher fuel efficiency or boost. However, the highly complex flow conditions of such a configuration in which to sweeping speed range were underestimated.

For all flight tests that Kuznetsov NK -15 engines (stage 1 ) were or NK -15W (2nd stage ) are used. The first stage of N1, total trade -off thrust of about 43,300 kN. The engines were later developed into Kuznetsov NK -33 ( depending 1.5102 or 1.638 MN sea level / vacuum thrust). The improved engines NK -33 ( 1st stage) and NK -43 (2nd stage) were from the year 1974 for use in the modification N1F ready (LEO payload of up to 105 tons ), but experienced by the program termination never a start in the N1.

It at least eleven copies were planned, including a mock-up (N1- 1M1 ) and ten flyable missiles ( N1 -3L to N1 -7L or N1F -8L -12L to N1F ). The use of the improved engines NK -33 was provided from the planned for August 1974 test of N1F -8L ( the improved version N1F ). With the N1F -L10 the first manned Soviet lunar landing for about 1976 was provided.

Naming

The N1 rocket never got a real name. The occasionally mentioned in various publications Gerkules name (Russian for Hercules ), Raskat, Lenin, Nauka, or giant are purely speculative.

Development

In May 1962, the unusual cone-shaped design was completed with spherical tanks of a three-stage N1. You should have a launch mass of 2200 tons and a payload of 75 tons for the near-Earth region. The project was approved on 24 September 1962, the Soviet government and the deadline for the realization of three years were used. There were 500 organizations from 26 ministries involved in the project, which led to difficulties in the project organization by lack of cooperation and coordination as well as competitors scramble in the further course.

On 1 August 1964, the Soviet manned lunar program was finally split into two projects by Council of Ministers Decree ( 655-268 ). By the term LK -1 or later Zond in OKB -52 of Tschelomei ran a circumnavigation program. The OKB of Korolev received with his project N1 -L3 the contract for the moon landing. The first flight to the moon was ambitious planned for November 1967. The rocket had to be redesigned for it, because now a direct start was planned to the moon, which increased the required payload to 95 tons. For this, the first stage were supplemented by six additional engines, spherical tanks enlarged and planned, the kerosene cooled to increase the density to refuel by cylindrical spacers. Thus, the initial weight increased to 2,750 tons. After the death of Korolev in January 1966 took over Vasily Mishin, who had played a major role in the reconstruction of the German A4 rocket and in the development of the first Soviet ICBM Semjorka R -7, the management of the OKB -1. However, it soon became apparent that political sensitivity and skill of his predecessor, he lacked - one of the reasons for the delays and the subsequent failure of the project. On February 4, 1967, the moon program was 115-46, the long-awaited high priority and the necessary funds by the Government Decision no. So now put the military on a large scale workers to complete the ground work for the launch facilities. When the launch pad PU was completed 38, 1967 was only a mock-up of the rocket rolls to the launch pad, as the first rocket to 1969 was slow in coming.

Due to time and cost reasons, did not prepare a test bed for the complete first stage. Since the Baikonur complex could not be hit by heavy-duty vans, the N1 had to be disassembled and reassembled on site. So it was that vibration and flow problems, the drive gases were not properly assessed before the flight. The attitude control about the longitudinal axis in the operation of the first stage proved to be inadequate - it renounced its own attitude control thrusters, the tasks should take variable exhaust nozzle of the turbo pump. Only after the resulting crash of the third prototype controllable engines were used for roll stabilization.

Failed test flights

The N1 has finally completed no flight successfully. All four test flights between 1969 and 1972 ended with crashes - even before the ignition of the second stage or the immediately thereafter taking place burnout of the first stage. An already planned for 1968 unmanned test ( N1 -4L ) had to be canceled after the erection of the rocket, as hairline cracks found in the oxygen tank of the first stage.

• The first launch attempt (N1 -3L ) was held on 21 February 1969. Shortly after takeoff, a fire developed in the rear of the rocket. The control system of the engines discovered this fire (after about 54 s ) and switched after 68.7 s mistake from all engines. As payload was a modification 7K- L1S ( s / n 3 ) of the 7K- L1 use developed for the lunar orbit. The rescue system separated the spacecraft before the explosion of the N1 -3L, it landed safely by parachute.
• The second launch attempt (N1 -5L ) took place on July 3, 1969, which is only about three weeks before the successful Apollo 11 moon landing and ended in disaster. Already during take-off, it came with a " foreign body" (possibly a metal chip ), which fell into one of the oxygen pump (No. 8), whose explosion. The automatic engine control switched in a sequence of errors then after a total of about 10 s ultimately 29 of 30 Erststufentriebwerke from. The rocket fell with even a running engine back in an inclined position from 200 m altitude and beat about 23 seconds after liftoff on. In the explosion, many plants were destroyed at the launch site. Then was categorically demanded from the line of the starting complex for its protection a lateral pivoting of the N1 immediately after takeoff. Even the first-stage engines should be able to be turned off too soon in any case after takeoff. The only thing that worked, was once again the rescue system; about 15 seconds after lift-off while transporting the spacecraft 7K- L1S ( s / n 5) time out of the danger zone.
• For the third start on 26 June 1971, the required modifications have been realized. The N1 -6L raised by asymmetrical thrust of the main engines from the side and then went on in the climb. The aerodynamic characteristics of this maneuver (lateral flow to the rocket and the asymmetric jet blast ) resulted in an uncontrollable by the position control roles, which led between the 45th and 50th seconds after lift-off to loss of control and the incipient decomposition of the structure. The forcible suppression used an automated shutdown of the engines ended as scheduled after 50 s, after which the position control shuts down the engine after 51 seconds. Then the rocket was destroyed by radio command. The limited roll stabilization of the N1 was not originally designed for such a complex lateral maneuvering. At least but had worked in this experiment all the engines of the first stage until canceled satisfactory. This initial attempt to serve exclusively the qualification of the carrier system. As payload therefore dummies were using, so was abandoned on the rescue system.
• The fourth start of the largely improved N1 -7L on 23 November 1972 ran until the end of firing the six central Erststufentriebwerke from problems. Their abrupt shutdown to prevent structural overload led to compression shocks in the fuel system, tearing at least one oxygen line, the explosion of engine No. 4 and ultimately the crash of the N1 -7L after about 107 seconds. The explosion was seven seconds before the scheduled separation of the first and second stage. Subsequent analyzes showed that at a separation about 2 s No. 4, the hitherto reached flying speed and height would have allowed a successful continuation of the mission before the explosion of the engine. However, such a scenario was never previously considered. First mockup of the lunar spacecraft 7K- LOK and now at the missions Kosmos 379, 398 and 434 in Earth orbit tested Landers LK were included.

Effects

The plans for a manned Soviet lunar landing were then step by step further postponed and finally canceled in 1974. Although Vasily Mishin continued to work on the N1 continuing in the hope of being able to use them, among other things as a launch vehicle for the transport of a manned space station, comparable to the U.S. Skylab. The entire N1 program was finally completed in 1974 but, after the OKB -1 with the founding of the RKK Energia Production Association rose on May 22, 1974, led by Valentin Glushko in this. This demolition took place in front of a promising engineers according another test flight of the equipped with NK -33 N1F -8L in the last quarter of 1974. At the time of program Abbruches the N1F -9L was already largely completed. Both missions were unmanned landings of the Moon Landers LK goal. The remaining Baikonur 8L was disassembled and used for other purposes as building material in many parts of the city and its surroundings.

Specifications

• Five-stage liquid rocket
• Start of development: 1960
• First flight: February 21, 1969
• Last flight: November 23, 1972
• Number of Starts: 4
• False starts: 4
• Reliability: 0%
• Height: 105.3 m
• Take off weight: 2750 t
• Total thrust: 43.3 MN
• Mass: 277 t
• Payload (LEO ): 70 t ( N1), later 95 t planned ( N1F )
• Fuel: RP -1 (kerosene - type ) / liquid oxygen

Start list

This is a complete start list of the rocket N1.