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 , and so named for its shape) is a vehicle that uses jet propulsion to accelerate without using any surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely ...

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 is a reaction engine, producing thrust in accordance with Newton's third law by ejecting reaction mass rearward, usually a high-speed Jet (fluid), jet of high-temperature gas produced by the combustion of rocket propellants stor ...

used

nitric acid Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most com ...

and UDMH as

rocket propellant Rocket propellant is used as reaction mass ejected from a rocket engine to produce thrust. The energy required can either come from the propellants themselves, as with a chemical rocket, or from an external source, as with ion engines. Overvi ...

s. 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 capacity compared to the earlier Thor-Able. It also incorporated restart capabilities, allowing a multiple-burn

trajectory A trajectory or flight path is the path that an object with mass in motion follows through space as a function of time. In classical mechanics, a trajectory is defined by Hamiltonian mechanics via canonical coordinates; hence, a complete tra ...

to be flown, further increasing payload, or allowing the rocket to reach different

orbit In celestial mechanics, an orbit (also known as orbital revolution) 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 ...

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 (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...

tube for the engine thrust chamber. 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 an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

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 the 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 t ...

between the US and

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

. 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 Animals in space originally served to test the survivability of spaceflight, before human spaceflights were attempted. Later, many species were flown to investigate various biological processes and the effects microgravity and space flight m ...

test, a

rhesus monkey The rhesus macaque (''Macaca mulatta''), colloquially rhesus monkey, is a species of Old World monkey. There are between six and nine recognised subspecies split between two groups, the Chinese-derived and the Indian-derived. Generally brown or g ...

named Miss Able, flew with Miss Baker on May 28, 1959.

Specifications

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

Specific impulse Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine, such as a rocket engine, rocket using propellant or a jet engine using fuel, generates thrust. In general, this is a ratio of the ''Impulse (physics), ...

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

References

{{Thor and Delta rockets Rocket stages

Specifications

See also

References