Tag Archives: NASA

22 August 1963

Joe Walker and the X-15 on Rogers Dry Lake at the end of a flight. Walker is wearing a David Clark Co. MC-2 full-pressure suit. (U.S. Air Force)

22 August 1963: On his twenty-fifth and last flight with the X-15 program, NASA Chief Research Test Pilot Joseph Albert Walker would attempt a flight to Maximum Altitude. Engineers had predicted that the X-15 was capable of reaching 400,000 feet (121,920 meters) but simulations had shown that a safe reentry from that altitude was risky. For this flight, Flight 91, the flight plan called for 360,000 feet (109,728 meters) to give Walker a safety margin. Experience had shown that slight variations in engine thrust and climb angle could cause large overshoots in peak altitude, so this was not considered an excessive safety margin.

For this flight, Joe Walker flew the Number 3 X-15, 56-6672. It was the only one of the three North American Aviation X-15s equipped with the Honeywell MH-96 flight control system, which had been developed to improve control of the rocketplane outside Earth’s atmosphere. This flight was the twenty-second for Number 3.

North American Aviation X-15 56-6672 immediately after being dropped by the Boeing NB-52 Stratofortress. (NASA)
North American Aviation X-15A 56-6672 immediately after being dropped by the Boeing NB-52 Stratofortress. (NASA)

Walker and the X-15 were airdropped from the Boeing NB-52A Stratofortress 52-003, The High and Mighty One, at 45,000 feet (13,716 meters) above Smith Ranch Dry Lake, Nevada, about half-way between the city of Reno and the NASA High Range Tracking Station at Ely. Launch time was 10:05:57.0 a.m., PDT. Walker ignited the Reaction Motors XLR99-RM-1 rocket engine. This engine was rated at 57,000 pounds of thrust. Experience had shown that different engines varied from flight to flight and that atmospheric conditions were a factor. Thrust beyond 60,000 pounds was often seen, but this could not be predicted in advance. The flight plan called for the duration of burn to be 84.5 seconds on this flight. The X-15 climbed at a 45° angle.

As Walker was about to shut down the engine according to plan, it ran out of fuel. The total burn time was 85.8 seconds, just slightly longer than planned.

“At burnout, Joe was passing 176,000 feet [53,645 meters] and traveling at 5,600 feet per second [1,707 meters per second]. He then began the long coast to peak altitude. It would take almost 2 minutes to reach peak altitude after burn out. Two minutes does not seem like a lot of time, but try timing it. Just sit back in your easy chair and count off the seconds. It is almost impossible to believe that you can continue to coast up in altitude for that length of time after the engine burns out. It gives you some feel for how much energy is involved at those speeds. For comparison, when you throw a ball up in the air as hard as you can, it only coasts upward a maximum of 4 or 5 seconds. The X-15 coasted up for 120 seconds.

“The airplane would coast up another 178,000 feet [54,254 meters] during that time to peak out at 354,200 feet. . . .” [107,960 meters]

At The Edge of Space: The X-15 Flight Program, by Milton O. Thompson, Smithsonian Institution Press, Washington, 1992, Chapter 5 at Page 125.

Joe Walker and the X-15 reached the peak of their ballistic trajectory at 354,200 feet (67.083 miles, 107,960 meters). Walker pitched the nose down to be in the proper attitude for atmospheric reentry. The X-15 decelerated as it hit the atmosphere and Walker experienced as much as 7 Gs. The rocketplane’s aerodynamic control surfaces again became operational as it descended through 95,000 feet (28,956 meters) and Walker leveled at 70,000 feet (21,336 meters). He then glided to a landing on Rogers Dry Lake at Edwards Air Force Base, California, after 11 minutes, 8.6 seconds of flight.

Flight 91 was the highest flight achieved by any of the X-15s. It was Joe Walker’s second flight into space. His record would stand for the next 41 years.

© 2016, Bryan R. Swopes

20 August 1977

Voyager 2/Titan IIIE-Centaur launch, LC-41, Kennedy Space Center, Florida, 20 August 1977. (NASA)

20 August 1977: Voyager 2 was launched from Launch Complex 41 at the Kennedy Space Center, Cape Canaveral, Florida, aboard a Titan IIIE-Centaur launch vehicle. It was placed on an orbital trajectory that would take it on a journey throughout the Solar System and beyond.

Nearly two years later, 9 July 1979, Voyager 2 made its closest approach to Jupiter, passing within 350,000 miles (570,000 kilometers) of the planet. Many dramatic images as well as scientific data were transmitted back to Earth.

Artist’s concept of Voyager. (NASA/JPL)

The probe continued outward to Saturn, Neptune and Uranus, continuously transmitting images and data. In 1990, the space probe passed beyond the limits of the Solar System.

Voyager 2 is now in interstellar space. It crossed the heliopause, where “solar wind” is slowed by the pressure of interstellar gas, 5 November 2018. It is still operating, 46 years after it was launched.

Voyager 2 captured this image of the moon Io transiting Jupiter, 9 July 1979. (NASA)
Uranus, imaged by Voyager 2, 24 January 1986. (NASA/JPL–Caltech)
This image of Neptune was captured by Voyager 2 on 20 August 1989, 28 years ago. (NASA)

On 21 July 2023, an erroneous instruction caused Voyager 2 to turn its antenna away from Earth, but on 5 August 2023, contact was reestablished. A power reduction strategy is hoped to allow the space probe to continue operating until 2026.

As of 15 August 2024, Voyager 2 was 136 Astronomical Units from Earth (20,345,310,413 kilometers/12,641,989,788 statute miles/10,985,588,776 nautical miles). Radio signals, traveling at the Speed of Light, take 18 hours, 56 minutes to cross that distance. It continues outbound at a rate of 3.3 AU/year. (With respect to the Sun, Voyager 2 is traveling outbound at 15.35 kilometers per second (33,330.48 miles per hour/29,832.37 knots).

© 2024, Bryan R. Swopes

20 August 1975

Viking 1/Titan IIIE-Centaur launches from Kennedy Space Centaur, enroute to Mars, 20 August 1975. (NASA)

20 August 1975: The Viking 1 space probe was launched from Kennedy Space Center, Cape Canaveral, Florida, aboard a Titan IIIE/Centaur rocket. For the next ten months it traveled to Mars, the fourth planet of the Solar System. Once there, it was placed in orbit and began sending telemetry data back to Earth. A Viking Lander descended to the planet’s surface, landing at Chryse Planitia.

This was the first time that a spacecraft had landed on another planet. The orbiter continued to operate over the course of 1,485 orbits. As it ran low on fuel, mission controllers boosted it into a higher orbit to prevent it falling to the planet. Orbiter operations were terminated 17 August 1980. The lander operated for 6 years, 116 days, before the mission was terminated by a faulty transmission which resulted in a loss of contact, 11 November 1982.

The surface of Chryse Planitia, Mars, photographed by the Viking 1 Lander. (NASA)

© 2015, Bryan R. Swopes

12 August 1977

Space Shuttle prototype Enterprise separates from NASA 905 for its first free flight, 12 August 1977. (NASA)

12 August 1977: At Edwards Air Force Base, California, the prototype Space Shuttle Oriter, Enterprise, (OV-101) was mated to the Boeing 747-100 Shuttle Carrier Aircraft, N905NA, call sign NASA 905, for the first of five approach and landing test flights. On Enterprise‘ flight deck were astronauts Fred Haise and Gordon Fullerton. The crew of NASA 905 were NASA test pilots Fitz Fulton and Tom McMurty with Vic Horton and Skip Guidry as flight engineers.

Space Shuttle Enterprise during the first free flight, 12 August 1977. (NASA)

An estimated 65,000 people had come to Edwards to watch and at 8:00, Fitz Fulton began the take off roll down Runway 22. For the next 38 minutes the spacecraft/aircraft combination climbed together into the desert sky. After reaching an altitude of 24,100 feet (7,346 meters), Fulton put the Shuttle Carrier Aircraft into a shallow dive. At 8:48 a.m., Fred Haise fired the seven explosive bolts holding the two craft together. The 747 entered a descending left turn while Haise banked Enterprise away to the right.

Space Shuttle Orbiiter Enterprise during a glide test. (NASA)
Space Shuttle Orbiter Enterprise during a glide test. (NASA)

As Enterprise made its gliding descent, Haise and Fullerton experimented with the prototype’s flight characterisics and handling. The Shuttle Orbiter touched down on Rogers Dry Lake at 185 miles per hour (297.7 kilometers per hour), and rolled for two miles (3.22 kilometers) before coming to a complete stop.

The first free flight of Enterprise lasted 5 minutes, 21 seconds.

Space Shuttle Enterprise banks to the left to line up with the runway on Rogers Dry Lake. (NASA)
Space Shuttle Enterprise banks to the left to line up with the runway on Rogers Dry Lake. (NASA)

© 2019, Bryan R. Swopes

12 August 1960, 09:39:43 UTC

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