Program Vanguard

Vanguard is the name of a program of American launchers at the base of the technological development from which the other US launchers will profit. The first stage of Vanguard comes from the launcher Viking. The second stage comes from the probe rockets Aerobie. The third stage is the only one with being of original design.

History

HATV and SSTO

The first project was to consist in the realization of a rocket of research to high-altitude (High Altitude Test Vehicle (HATV)) and on only one floor burning of hydrogen liquidates with liquid oxygen (Individual Training course To Orbite (SSTO)).

This project was entrusted to the company Glenn Martin (Lockheed Martin) in 1946, in partnership with North American, (Rockwell - Boeing Aerojet) as motor mechanic.

The rocket would have had like characteristics:

Length: 26,2 meters;
Diameter: 4,9 m;
Weight with launching: 45,8 tons;
Thorough: 136 tons;
Payload: 450 G.

The program, too ambitious, did not exceed the stage of simple project. Nowadays (2004), no SSTO was born.

Viking

The launcher Viking (at the origin named Neptune) was more realistic and more at the technological level of the time (1946).

The launchers Viking were directly derived from the German rockets V-2. The Viking were to replace V-2, available in limited quantity, in the missions of survey of the upper atmosphere and for astronomical observations. The project was also entrusted to Glenn Martin.

The technology of the Viking is about identical to that of V-2, except for some differences. First of all, the structure is out of aluminum, much lighter than that out of steel of V-2, conceived to support the heat of the atmospheric Rentrée (the technique of “separation” of the launcher of its payload had not been invented yet at the time of the Second world war). The development of the engine of the Viking is entrusted to Reaction Motor. This engine was less powerful than that of V-2 (less low total load).

The engine was to develop 9,1 tons of average (from 8,5 to 9,7 tons).

The “piloting” of the Viking was done thanks to an articulation Cardan joint which made it possible the engine to be inclined on 2 axes to ensure the stability of the rocket. Information of piloting came from the gyroscopic stabilizing brain located in the superior part of the rocket. After the shutdown, intermittent gas jets ensured the stability of the rocket.

; Characteristics of the rocket for the first seven flights (May 3rd, 1947 at August 7th, 1951):

Length: 13,8 to 14,8 meters;
Diameter: 0,81 m;
Weight with launching: 4,4 to 5,2 tons;
Thorough: 8,5 to 9,7 tons.

; Characteristics of the rocket for the 5 following flights (June 6th, 1952 at February 4th, 1955), Viking II:

Length: 12,7 to 13,7 meters;
Diameter: 1,14 m;
Weight with launching: 5,8 to 6,8 tons;
Thorough: 8,5 to 9,7 tons.

The last 2 flights of the Viking will be registered later, within the framework of the program Vanguard, the December 8th, 1956 and May 1st, 1957.

Vanguard

The Vanguard project is born on July 5th, 1955 with the publication of a report/ratio on a program of scientific satellites by the Naval Research Laboratory.

This report/ratio recommends the use of the Viking like first stage of the launcher, and of the upper floors consisting of two stages with solid propellent or a second stage with liquid propellent derived from the rocket probes Aerobee and a third stage with solid propellent.

The plan is approved on July 29th, 1955 by Dwight Eisenhower.

The first international geophysical Year (1957-58), within the framework of which one hoped to highlight the existence of a belt of radiations around the Earth is used as justification with the launching of an artificial satellite. The Vanguard launcher was to be ready for this event.

The project Vanguard, entirely American, was preferred with the Projet To orbit which used a first stage designed by the team of Werner von Braun, of old Nazi S.

Characteristics of Vanguard

The version SLV 7 which stole in September 1959 only once is equipped with a new third stage with an engine X 248-A2. The capacity of launching is of 45 kg in low orbit.

The first stage is identical to that of Viking II (1,14 m diameter for 13,4 m height), but the engine is developed by General Electric. The new engine, called X-405, provided a push of 12,7 tons during 142 S (against 9,7 tons for the preceding engines) thanks to the use of the kerosene (with liquid oxygen like oxidant).

The second stage, (0,81 m diameter for a 9,4 m height, identical to Viking I) uses an engine derived from that of the Aerobie rocket but more powerful (3,4 tons compared with 1,1 tons of pushed during 120 S), the AJ-10. The “piloting” of the second stage was done according to the same principle as that of the Viking (articulation Cardan joint). The fuel of the second stage of Vanguard was unsymetrical dimethylhydrazine (UDMH) with nitric Acid smoking like oxidant.

The third stage with solid propellent (powder) measurement 1,5 m in height for 50 cm in diameter and provides a push of 1 tons (engine GRC 133-KS-2800). The engine of version SLV-7 is provided by Hercules Powder. This engine, X-248, develops 1,4 tons of thorough by burning a mixture of nitrocellulose and nitroglycerin, with addition of perchlorate of aluminum ammonium and powder, inter alia. The body of the engine is out of glass fiber.

The payload is of 45 kg in low orbit.

Missions

Fourteen launchings of Viking will take place (against the 12 envisaged at the beginning). The two last will carry the designation of Vanguard Test Vehicle TV0 and TV1. True launchings “Vanguard” strictly speaking, start with Vanguard TV2. Last launching takes place on September 18th, 1959 after 12 launchings and three satellites (Vanguard 1,2 and 3) placed in orbit.

The success of the Soviet Sputnik in 1957, accelerates launchings so much so that the launching of a satellite, initially envisaged with Vanguard TV6, is advanced with the TV3 with like consequence, the destruction of the launcher in its launching pad.

Order of the missions

December 8th, 1956: Vanguard TV0 (not of satellite), made a success of
May 1st, 1957: Vanguard TV1 (not of satellite), made a success of
October 23rd, 1957: Vanguard TV2 (not of satellite), fails
December 6th, 1957: Vanguard TV3 (sat #1 of 6,5 inches), fails
February 5th, 1958: Vanguard TV3BU (sat #2 of 6,5 inches), fails
March 17th, 1958: Vanguard TV4 (sat #3 of 6,5 inches (Vanguard 1)), made a success of
April 28th, 1958: Vanguard TV5 (X-ray #1 of 20 inches), fails
May 27th, 1958: Vanguard SLV-1 (Lyman-Alpha #1 of 20 inches), fails
June 26th, 1958: Vanguard SLV-2 (Lyman-Alpha #2 of 20 inches), fails
September 26th, 1958: Vanguard SLV-3 (Cloud cover #1 of 20 inches), fails
February 17th, 1959: Vanguard SLV-4 (Cloud cover #2 of 20 inches (Vanguard 2)), made a success of
April 13rd, 1959: Vanguard SLV-5 (Magnetometer #1 of 13 inches), fails
June 22nd, 1959: Vanguard SLV-6 (Radiation balances #1 of 20 inches), fails
September 18th, 1959: Vanguard SLV-7 or Vanguard V-4BU (Magnetometer, X-Ray, Approx. #1 of 20 inches (Vanguard 3)), succeeded.

External bonds

About the Vanguard program, in English

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