Able rocket stage, is the second stage in the Vanguard rocket cutaway view Able rocket stage engine in the foreground The Able rocket stage was a

rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entire ...

stage manufactured in the United States by Aerojet as the second of three stages of the Vanguard rocket used in the Vanguard project from 1957 to 1959. The

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive Jet (fluid), jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, i ...

used

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 ni ...

and

UDMH 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 ...

as rocket propellants. The Able rocket stage was discontinued in 1960. The improved Ablestar version was used as the upper stage of the Thor-Ablestar two stage launcher. The Ablestar second stage was an enlarged version of the Able rocket stage, which gave the Thor-Ablestar a greater

payload Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...

capacity compared to the earlier Thor-Able. It also incorporated restart capabilities, allowing a multiple-burn trajectory to be flown, further increasing payload, or allowing the rocket to reach different

orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such a ...

s. It was the first rocket to be developed with such a capability and development of the stage took a mere eight months. A version of the AJ10 engine used for the Able rocket stage was used as the engine of Apollo Service Module. The Able stage name represents its place as the first in the series, from the Joint Army/Navy Phonetic Alphabet. To save weight Aerojet used an

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It h ...

tube for the engine

thrust chamber Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that syst ...

. The engine used on Vanguard was an AJ10-37. On later Able models rockets the AJ10-41 and AJ10-42 engines were used. Aerojet made 21 Able rocket stages for use on launchers. The Vanguard project launched 11 Able stages. Three put

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...

s into

: Vanguard 1, Vanguard 2 and Vanguard 3. The Able rocket stage and the Vanguard project were an important part of the

space race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the ...

between the US and

Soviet union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

. The AJ10 engines used in the Able rocket stage continue to be used on later rockets and are still in use. In honor of the rocket stage during an animals in space test, a rhesus monkey name Miss Able, flew with

Miss Baker Miss Baker (1957 – November 29, 1984) was a squirrel monkey who in 1959 became, along with female rhesus macaque Able, one of the first two animals launched into space by the United States who safely returned. Previous animal flights Previous ...

on May 28, 1959.David Darling, Able
/ref>

Specifications

*Loaded gross mass: *Empty (unfueled) mass *Thrust *

Specific impulse Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is ...

(vacuum) *Height: *Diameter: *Span: *Burn time: 115 seconds.

References

{{Thor and Delta rockets Rocket stages

Specifications

See also

References