Vanguard SLV-3, also called Vanguard Satellite Launch Vehicle-3 hoped to be the second successful flight of the American

Vanguard rocket The Vanguard rocket was intended to be the first launch vehicle the United States would use to place a satellite into orbit. Instead, the Sputnik crisis caused by the surprise launch of Sputnik 1 led the U.S., after the failure of Vanguard TV-3 ...

following successful

Vanguard 1 Vanguard 1 (Harvard designation: 1958-Beta 2, COSPAR ID: 1958-005B ) is an American satellite that was the fourth artificial Earth-orbiting satellite to be successfully launched, following Sputnik 1, Sputnik 2, and Explorer 1. It was laun ...

satellite on rocket Vanguard TV-4.

Background

Vanguard Satellite Launch Vehicle-3 (SLV-3) was launched on 26 September 1958. The second stage failed to achieve the minimal performance necessary to maintain Earth orbit, and the spacecraft re-entered the atmosphere and burned up. The objective of the satellite was to scan Earth's cloud cover from orbit. The purpose of the IGY Vanguard satellite program, run by the U.S. Navy, was to launch one or more satellites into Earth orbit during the International Geophysical Year (IGY).

Launch vehicle

Vanguard was the designation used for both the launch vehicle and the satellite. The first stage of the three-stage Vanguard Test vehicle was powered by a General Electric X-405 thrust liquid rocket engine, propelled by 7200 kg of

kerosene Kerosene, paraffin, or lamp oil is a combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in aviation as well as households. Its name derives from el, κηρός (''keros'') meaning "wax", and was regi ...

(

RP-1 RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. RP-1 provides a lower specific impulse than liquid hydrogen (LH2), but is cheaper, is s ...

) and

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an app ...

, with

helium Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...

pressurant. It also held 152 kg of

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

. It was finless, 13.4 metres tall, 1.14 metres in diameter, and had a launch mass of approximately 8090 kg. The second stage was a 5.8 metres high, 0.8 metres diameter Aerojet General

AJ-10 The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne (previously Aerojet). It has been used to propel the upper stages of several launch vehicles, including the Delta II and Titan III. Variants were and are used as the ser ...

liquid engine burning 1520 kg

Unsymmetrical dimethylhydrazine Unsymmetrical dimethylhydrazine (UDMH; 1,1-dimethylhydrazine, НДМГ or codenamed Geptil) is a chemical compound with the formula H2NN(CH3)2 that is used as a rocket propellant. It is a colorless liquid, with a sharp, fishy, ammonia-like smell ...

(UDMH) and

White Inhibited Fuming Nitric Acid Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric ...

(WIFNA) with a

pressurant tank. It produced a thrust of and had a launch mass of approximately 1990 kg. This stage contained the complete guidance and control system. A solid-propellant rocket with ) of thrust (for 30 seconds burn time) was developed by the

Grand Central Rocket Company The Lockheed Propulsion Company was a division of the Lockheed Aircraft Corporation located at 1500 Crafton Avenue in the Mentone, California area northeast of Redlands, California, adjacent to the Santa Ana River, from 1961 to 1975. It developed, ...

to satisfy third-stage requirements. The stage was 1.5 metres high, 0.8 metres in diameter, and had a launch mass of 194 kg. The thin (0.076 cm) steel casing for the third stage had a hemispherical forward dome with a shaft at the center to support the satellite and an aft dome fairing into a steel exit nozzle. The total height of the vehicle with the satellite fairing was about 21.9 metres. The payload capacity was 11.3 kg to a 555 km Earth orbit. A nominal launch would have the first stage firing for 144 seconds, bringing the rocket to an altitude of 58 km, followed by the second stage burn of 120 seconds to 480 km, whereupon the third stage would bring the satellite to orbit. This was the same launch vehicle configuration, with minor modifications, as used for

Vanguard TV-3 Vanguard TV-3 (also called Vanguard Test Vehicle-Three), was the first attempt of the United States to launch a satellite into orbit around the Earth, after the successful Soviet launches of Sputnik 1 and Sputnik 2. Vanguard TV-3 was a small s ...

and all succeeding Vanguard flights up to and including

Vanguard SLV-6 Vanguard SLV-6, also called Vanguard Satellite Launch Vehicle-Six, hoped to be the third successful flight of the American Vanguard rocket following the successful Vanguard 2 satellite on rocket Vanguard SLV-4. Vanguard Satellite Launch Vehicl ...

Spacecraft

Vanguard SLV-3 hoped to put into orbit the Vanguard 2D satellite, a Lyman Alpha satellite, with a magnetosphere measurement device. The satellite payload was . Vanguard SLV-3 only reached an altitude of , the goal was to orbit. The SLV-3 satellite was a 10.6 kg, 50.8 cm diameter

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...

sphere. The interior was pressurized. The payload

instrumentation Instrumentation a collective term for measuring instruments that are used for indicating, measuring and recording physical quantities. The term has its origins in the art and science of scientific instrument-making. Instrumentation can refer to ...

package was mounted in the center of the sphere. The package was arranged in a cylindrical stack with mercury batteries at the bottom, followed by the

Minitrack The Minitrack Network was the first U.S. satellite tracking network to become operational, in 1957. It was used to track the flights of Sputnik, Vanguard, Explorer, and other early space efforts. Minitrack was the progenitor of Spacecraft Trackin ...

tracking system electronics, the environment electronics, the telemetering instrumentation, and the experiment electronics. Below the package at the bottom of the sphere was the separation device, a spring loaded tube with a timer designed to push the satellite away from the third stage after orbit was reached. At the top of the interior of the sphere was a pressure gauge. Four spring-loaded metal rods were folded along the equator of the sphere and would protrude radially outward when deployed, acting as a turnstile antenna. It used two transmitters: a 10 mW transmitter broadcasting at a frequency of 108.00

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

and a 1 watt transmitter broadcasting at 108.03 MHz. The payload contained two infrared-sensitive

photocells A photoresistor (also known as a photocell, or light-dependent resistor, LDR, or photo-conductive cell) is a passive component that decreases resistance with respect to receiving luminosity (light) on the component's sensitive surface. The resi ...

designed to scan the cloud cover of Earth.

Launch

An initial launch attempt on 17 September miscarried when a pad umbilical detached prematurely, causing first stage engine shutdown after one inch of vehicle rise. It settled back onto the launcher, but fortunately no damage resulted and Vanguard SLV-3 launched successfully on 26 September 1958 at 15:38

GMT Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London, counted from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a cons ...

. It was launched from Launch Complex 18A (LC-18A) at the

Cape Canaveral Air Force Station Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the statio ...

(CCAFS). Low second stage performance resulted in insufficient velocity for the third stage and payload. They completed one orbit and reached a peak altitude of before reentering over

Central Africa Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo ...

. Investigation concluded that particles from a rubber

fill hose had clogged a filter in the fuel feed system, resulting in the second stage engine being fuel-starved and operating at only 80% thrust. The fill hose was changed to metal on subsequent flights, the second stage propellant tanks heat-treated to remove scale, and preflight procedures changed to reduce the need to open up the propulsion system and potentially introduce contaminants into it.astronautix.com, Vanguard SLV-3
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Mission

Vanguard SLV-3 was launched from the

Atlantic Missile Range The Eastern Range (ER) is an American rocket range (Spaceport) that supports missile and rocket launches from the two major launch heads located at Cape Canaveral Space Force Station and the Kennedy Space Center (KSC), Florida. The range ha ...

in Cape Canaveral,

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

, on 26 September 1958 at 15:38 GMT. Flight was nominal during the liftoff period, but the performance of the second stage was below the anticipated minimum requirement. The third stage fired as planned, although separation from the second stage occurred about 50 seconds early, at 422.7 seconds after launch. The failure of the second stage resulted in a final velocity that was about 75

meters per second The metre (British spelling) or meter (American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its prefi ...

(250 feet per second) short of the roughly 7500 mps (25,000 fps) required to reach the planned orbit. The burned out third stage and satellite reached an altitude of almost 425 km (265 miles) before coming back down and burning up on re-entry into the atmosphere. This was believed to have occurred over

after completion of one orbit. The poor performance of the second stage was concluded to be a result of low fuel flow rate due to contamination from Buna-N rubber particles from the

fill hose.

Background

Launch vehicle

Spacecraft

Launch

Mission

See also

References

Further reading