Tag Archives: Launch Complex 17A

11 October 1958, 08:42:13 UTC

Aviation, , , , , , , , , ,
Pioneer 1 is readied for launch aboard a Thor Able I at Launch Complex 17A, Cape Canaveral Air Force Station. (NASA Image Number 73-H-787)

11 October 1958: At 08:42:13 UTC (3:42:13 a.m., Eastern Standard Time), Able 2 (later renamed Pioneer 1) was launched from Launch Complex 17A at the Cape Canaveral Air Force Station on the east coast of Florida., on a mission to orbit The Moon. The launch vehicle was Thor Number 130, DM-1812-6. The mission was carried out by the U.S. Air Force Ballistic Missile Division, the Advanced Research Projects Agency (ARPA), and the newly established National Aeronautics and Space Administration (NASA).

The Thor second stage shut down approximately 10 seconds earlier than planned. An accelerometer had cut off the engine because of an incorrect valve setting. As a result, the space probe did not achieve sufficient velocity to escape Earth’s gravity. It reached a maximum altitude of 71,303 miles (114,751 kilometers) at 11:42 UTC.

An attempt to insert the space probe into a 79,970 × 20,000 mile (128,699 × 32,187 kilometers) orbit failed. The internal temperatures were too cold for the stage’s batteries to ignite the solid fuel rocket engine. 43 hours after launch, Able 2 reentered the atmosphere at 03:46 UTC, 13 October 1958, over the South Pacific Ocean.

The Able 2 space probe is today designated Pioneer 1. It was built by the Ramo-Wooldridge Corporation’s Space Technology Laboratory (STL) in Redondo Beach, California.

The Thor Able was a two-stage orbital launch vehicle which was developed from the Douglas Aircraft Company’s SM-75 Thor intermediate-range ballistic missile.

Designated Thor DM-19, the first stage was 60.43 feet (18.42 meters) long and 8 feet (2.44 meters) in diameter. Fully fueled, the first stage had a gross weight of 108,770 pounds (49,337 kilograms). It was powered by a Rocketdyne LR-79-7 engine which burned liquid oxygen and RP-1 (a highly-refined kerosene rocket fuel) and produced 170,565 pounds of thrust (758.711 kilonewtons). This stage had a burn time of 2 minutes, 45 seconds.

The second stage was an Aerojet General Corporation-built Able, a second stage for the U.S. Navy’s Vanguard rocket. It was 21 feet, 6.6 inches (6.57 meters) long with a maximum diameter of 2 feet, 9 inches (0.84 meters), and had a gross weight of 5,000 pounds (2,268 kilograms). It used an Aerojet AJ10-101 rocket engine which burned a hypergolic mixture of nitric acid and UDMH. The second stage produced 7,711 pounds of thrust (34.300 kilonewtons) and burned for 1 minutes, 55 seconds.

The Altair X248 third stage was developed by the Alleghany Ballistics Laboratory for the U.S. Navy’s Vanguard rocket. It was 4 feet, 11 inches (1.499 meters) long, 2 feet, 7 inches (0.787 meters) in diameter, and weighed 505 pounds (229 kilograms). It was powered by a solid fuel rocket engine producing 2,300 pounds (10.231 kilonewtons) of thrust. Its burn time was 38 seconds.

Arrangement of equipment with the Pioneer lunar orbiter. (Drew ex Machina)
A Pioneer lunar orbiter attached to the third stage of the Thor-Able launch vehicle. (U.S. Air Force)

The lunar probe was the fourth stage of the Thor-Able launch vehicle. It was 74 centimeters (2 feet, 5.13 inches) in diameter, 76 centimeters (2 feet, 5.9 inches) long, and weighed 38.1 kilograms (83.996 pounds). The probe’s external shell was constructed of metal and fiberglass. It carried 11.3 kilograms (24.9 pounds) of instruments designed to measure magnetic fields, radiation and micrometeorites. It also carried an infrared camera system intended to obtain close-up images of The Moon’s surface. Pioneer 1 was spin-stabilized, turning 108 r.p.m.

The probe was equipped with a Thiokol TX-8-6 solid rocket engine to decelerate it for entry into lunar orbit. The rocket engine was the main structural component of the probe. There were 8 vernier rockets to correct its trajectory. The Thiokol TX-8 was produced at the U.S. Army’s Longhorn Army Ammunition Plant near Karnack, Texas. It was designed to power the GAR-1 Falcon radar-homing air-to-air guided missile (later designated AIM-4 Falcon). The rocket motor weighed 11 kilograms (24.3 pounds).

© 2024, Bryan R. Swopes

12 August 1960, 09:39:43 UTC

Space Flight, , , , , , , , , , , , , , , , , , , , ,
The Thor Delta launch vehicle at Launch Complex 17A, Cape Canaveral Air Force Station. The spherical capsule containing the Echo 1A is visible at the top of the Altair solid fuel third stage. (NASA)

12 August 1960: At 5:39:43 a.m., Eastern Daylight Savings Time, the Echo 1A experimental passive communications satellite was launched from LC-17A at Cape Canaveral Air Force Station, Florida. The launch vehicle was a Thor-Delta three stage rocket. It entered a nearly circular 944 mile × 1,048 mile orbit (1,519 × 1,687 kilometers). The orbital period was 118.3 minutes.

The satellite was a 100 foot diameter (30.48 meter) Mylar polyester balloon with a reflective surface. The material was just 0.0127 millimeters thick. The mass of the satellite was 66 kilograms (145.5 pounds). In orbit, the balloon envelope was kept inflated by gas from evaporating liquid. It had been constructed by the G.T. Schjeldahl Company, Northfield, Minnesota. This was the second Echo satellite. The first had failed to reach orbit when launched 13 March 1960.

Later the same day, a microwave transmission from the Jet Propulsion Laboratory, Pasadena, California, was reflected off the Echo 1A satellite and received at the Bell Laboratories, Homdel, New York.

According to NASA, “The success of Echo 1A proved that microwave transmission to and from satellites in space was understood and demonstrated the promise of communications satellites. The vehicle also provided data for the calculation of atmospheric density and solar pressure due to its large area-to-mass ratio. Echo 1A was visible to the unaided eye over most of the Earth (brighter than most stars) and was probably seen by more people than any other man-made object in space.”

Echo 1A remained in Earth orbit until 24 May 1968.

An Echo satellite undergoing static inflation tests inside a blimp hangar at Weeksville NAS, North Carolina. The vehicle, which shows scale, is a 1959 Plymouth Suburban 4-door station wagon. (NASA)

The Delta was a three-stage expendable launch vehicle which was developed from the Douglas Aircraft Company’s SM-75 Thor intermediate-range ballistic missile.

Designated Thor DM-19, the first stage was 60.43 feet (18.42 meters) long and 8 feet (2.44 meters) in diameter. Fully fueled, the first stage had a gross weight of 108,770 pounds (49,337 kilograms). It was powered by a Rocketdyne LR-79-7 engine which burned liquid oxygen and RP-1 (a highly-refined kerosene rocket fuel) and produced 170,565 pounds of thrust (758.711 kilonewtons). This stage had a burn time of 2 minutes, 45 seconds.

The second stage was an Aerojet General Corporation-built Delta 104. It was 19 feet, 3 inches (5.88 meters) long with a maximum diameter of 4 feet, 6 inches (1.40 meters). The second stage had a gross weight of 9,859 pounds (4,472 kilograms). It used an Aerojet AJ10-104 rocket engine which burned a hypergolic  mixture of nitric acid and UDMH. The second stage produced 7,890 pounds of thrust (35.096 kilonewtons) and burned for 4 minutes, 38 seconds.

The third stage was an Alleghany Ballistics Laboratory Altair 1. It was 6 feet long, 1 foot, 6 inches in diameter and had a gross weight of 524 pounds (238 kilograms). This stage used a solid-fuel Thiokol X-248 rocket engine, producing 2,799 pounds of thrust (12.451 kilonewtons). Its burn time was 4 minutes, 16 seconds.

© 2016, Bryan R. Swopes