Little Joe II
Encyclopedia
Little Joe II was an American space launch vehicle used for five unmanned tests of the launch escape system
Launch escape system
A Launch Escape System is a top-mounted rocket connected to the crew module of a crewed spacecraft and used to quickly separate the crew module from the rest of the rocket in case of emergency. Since the escape rockets are above the crew module, an LES typically uses separate nozzles which are...

 (LES) and to verify the performance of the command module parachutes for the Apollo spacecraft
Apollo spacecraft
The Apollo spacecraft was composed of five combined parts designed to accomplish the American Apollo program's goal of landing astronauts on the Moon by the end of the 1960s and returning them safely to Earth...

 from 1963–66. Launched from White Sands Missile Range
White Sands Missile Range
White Sands Missile Range is a rocket range of almost in parts of five counties in southern New Mexico. The largest military installation in the United States, WSMR includes the and the WSMR Otera Mesa bombing range...

 in New Mexico, it was the smallest of four boosters used in the Apollo program
Project Apollo
The Apollo program was the spaceflight effort carried out by the United States' National Aeronautics and Space Administration , that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President John F...

.
Little Joe II
Stages 2
0 - Booster Engines 5 * Recruit engines
Thrust 167 kN x 5 = 836 kN
Burn time 1.53 seconds
Fuels Solid
1 - Sustainer Engines 2 * Algol engines
Thrust 465 kN x 2 = 930 kN
Burn time 40 seconds
Fuels Solid
2 - Second stage Engines 2 * Algol engines
Thrust 465 kN x 2 = 930 kN
Burn time 40 seconds
Fuels Solid
A-004 version Launch January 20, 1966
Payload 30,000 lb (14,000 kg)

Background

The booster's predecessor, Little Joe, had been used in testing the launch escape system for the Mercury
Project Mercury
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

 spacecraft from 1959–60.

The program was originally planned to be conducted at the U.S. Air Force Eastern Test Range
Eastern Test Range
The Eastern Range is an American rocket range that supports missile and rocket launches from the two major launch heads located at Cape Canaveral Air Force Station and the Kennedy Space Center. The range has also supported Ariane launches from the Guiana Space Centre as well as providing support...

 at Cape Kennedy
Cape Canaveral Air Force Station
Cape Canaveral Air Force Station is an installation of the United States Air Force Space Command's 45th Space Wing, headquartered at nearby Patrick Air Force Base. Located on Cape Canaveral in the state of Florida, CCAFS is the primary launch head of America's Eastern Range with four launch pads...

, Florida. However, because of a heavy schedule of high-priority launches at that facility, other possible launch sites were evaluated including Wallops Flight Facility
Wallops Flight Facility
Wallops Flight Facility , located on the Eastern Shore of Virginia, is operated by NASA’s Goddard Space Flight Center, primarily as a rocket launch site to support science and exploration missions for NASA and other U.S. government agencies...

, Wallops Island, Virginia, and Eglin Air Force Base
Eglin Air Force Base
Eglin Air Force Base is a United States Air Force base located approximately 3 miles southwest of Valparaiso, Florida in Okaloosa County....

, Florida. Launch Complex 36 at White Sands Missile Range, previously used for Redstone missile tests, was ultimately selected as the most suitable for meeting schedule and support requirements. White Sands also allowed land recovery which was less costly and complicated than the water recovery that would have been required at the Eastern Test Range or at the NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 Wallops Island
Wallops Island
Wallops Island is a island off the east coast of Virginia, part of the barrier islands that stretch along the eastern seaboard of the United States of America.It is located in Accomack County, Virginia...

 facility.

The program was conducted under the direction of the Manned Spacecraft Center (now Johnson Space Center), Houston, Texas
Houston, Texas
Houston is the fourth-largest city in the United States, and the largest city in the state of Texas. According to the 2010 U.S. Census, the city had a population of 2.1 million people within an area of . Houston is the seat of Harris County and the economic center of , which is the ...

, with joint participation by the prime contractors for the launch vehicle (General Dynamics
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...

/Convair
Convair
Convair was an American aircraft manufacturing company which later expanded into rockets and spacecraft. The company was formed in 1943 by the merger of Vultee Aircraft and Consolidated Aircraft, and went on to produce a number of pioneering aircraft, such as the Convair B-36 bomber, and the F-102...

) and spacecraft (North American Rockwell). The White Sands Missile Range administrative, range, and technical organizations provided the facilities, resources, and services required. These included range safety, radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 and camera tracking, command transmission, real-time data displays, photography, telemetry data acquisition, data reduction, and recovery operations.

Launch vehicle development

Man-rating of the launch escape system was planned to be accomplished at minimum cost early in the Apollo program. Since there were no reasonably priced launch vehicles with the payload capability and thrust versatility that could meet the requirements of the planned tests, a contract was awarded for the development and construction of a specialized launch vehicle. Fabrication
Fabrication (metal)
Fabrication as an industrial term refers to building metal structures by cutting, bending, and assembling. The cutting part of fabrication is via sawing, shearing, or chiseling ; torching with handheld torches ; and via CNC cutters...

 of the detail parts for the first vehicle started in August 1962, and the final factory systems checkout was completed in July 1963. There was an original fixed-fin configuration and a later version using flight controls.
The vehicle was sized to match the diameter of the Apollo spacecraft service module and to suit the length of the Algol rocket motors. Aerodynamic fins were sized to assure that the vehicle was inherently stable. The structural design was based on a gross weight of 220,000 pounds (100,000 kg), of which 80,000 pounds (36,000 kg) was payload. The structure was also designed for sequential firing with a possible 10-second overlap of four first-stage and three second-stage sustainer motors. Sustainer thrust was provided by Algol solid-propellant motors. Versatility of performance was achieved by varying the number and firing sequence of the primary motors (capability of up to seven) required to perform the mission. Recruit rocket motors were used for booster motors as required to supplement lift-off thrust.

A simplified design, tooling, and manufacturing concept was used to limit the number of vehicle components, reduce construction time, and hold vehicle cost to a minimum. Because overall weight was not a limiting factor in the design, over designing of primary structural members greatly reduced the number and complexity of structural proof tests. Whenever possible, vehicle systems were designed to use readily available off-the-shelf components that had proven reliability from use in other aerospace programs, and this further reduced overall costs by minimizing the amount of qualification testing required.

The Little Joe II launch vehicle proved to be very acceptable for use in this program. Two difficulties were experienced. The qualification test vehicle (QTV) did not destruct when commanded to do so because improperly installed primacord
Primacord
Primacord is a registered trademark of detonating cord used in blasting, originally manufactured by the Ensign-Bickford Company. Ensign Bickford sold the trademark to Dyno Nobel Inc in 2003 and it is now manufactured in Graham, Kentucky...

 did not propagate the initial detonation to the shaped charges on the Algol engine case. The fourth mission (A-003) launch vehicle became uncontrolled about 2.5 seconds after lift-off when an aerodynamic fin moved to a hard over position as the result of an electronic failure. These problems were corrected and the abort test program was completed.

Minor spacecraft design deficiencies in the parachute reefing cutters, the drogue and main parachute deployment mortar mountings, and the command module/service module umbilical cutters were found and corrected before the manned Apollo flights began. However, all command modules flown achieved satisfactory landing conditions and confirmed that, had they been manned spacecraft, the crew would have survived the abort conditions.

Flights

The first launch, on August 28, 1963, carried an aluminum shell designed to look like an Apollo capsule with an LES attached. This flight proved the booster would work. The second launch, on May 13, 1964, carried a boilerplate capsule, BP-12, and performed the first successful abort using the new escape system. A third launch, using BP-23, tested the effectiveness of the LES when the pressures and stresses on the spacecraft were similar to what they would be during a real launch. The fourth flight, with BP-22 on May 19, 1965, was designed to test the escape system at a high altitude. The final launch, on January 20, 1966, carried CSM-002.

In addition, two pad abort test
Pad abort test
A pad abort test is a test of a launch escape system to determine how well the system could get the crew of a spacecraft to safety in an emergency on the launch pad.- Project Mercury :Section sources....

s were conducted in which the launch escape system was activated at ground level.

Launch configuration summary

Item QTV A-001 A-002 A-003 A-004
Launch weight 25,930 kg 26,281 kg 42,788 kg 80,372 kg 63,381 kg
Payload 10,988 kg 11,492 kg 12,561 kg 12,626 kg 14,717 kg
Airframe weight 14,942 kg 14,785 kg 29,320 kg 67,745 kg 48,623 kg
Liftoff thrust 49 kN 49 kN 1,600 kN 1,395 kN 1,766 kN
Fin – fixed/control F F C C C
1st stage Recruit engine 6 6 4 0 5
1st stage Algol engine 1 1 2 3 2
2nd stage Algol engine 0 0 0 3 2


Surviving examples

  • New Mexico Museum of Space History, Alamogordo, New Mexico
  • Johnson Space Center
    Lyndon B. Johnson Space Center
    The Lyndon B. Johnson Space Center is the National Aeronautics and Space Administration's center for human spaceflight training, research and flight control. The center consists of a complex of 100 buildings constructed on 1,620 acres in Houston, Texas, USA...

    , Houston, Texas

Specifications

  • Little Joe II
    • Thrust: 49 to 1,766 kN
    • Length: 10.1 m without - CM/SM/LES
    • Length: 26.2 m with CM/SM/LES
    • Diameter: 3.9 m body
    • Fin span: 8.7 m
    • Weight: 25,900 to 80,300 kg
    • Fuel: solid
    • Burn time: ~50 s

  • Algol engine
    • Thrust: 465 kN each
    • Length: 9.1 m
    • Diameter: 1 m
    • Weight full: 10,180 kg
    • Weight empty: 1,900 kg
    • Fuel: solid
    • Burn time: 40 s

  • Recruit engine (Thiokol XM19)
    • Thrust: 167 kN
    • Length: 2.7 m
    • Diameter: 0.23 m
    • Weight: 159 kg
    • Fuel: solid
    • Burn time: 1.53 s

External links


Previous Mission:
Saturn I
Saturn I
The Saturn I was the United States' first heavy-lift dedicated space launcher, a rocket designed specifically to launch large payloads into low Earth orbit. Most of the rocket's power came from a clustered lower stage consisting of tanks taken from older rocket designs and strapped together to make...

Apollo program Next Mission:
Saturn IB
Saturn IB
The Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration for use in the Apollo program...

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