NASA Logo, National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive Header

Vanguard TV5



Vanguard TV-5 launched on 29 April (28 April ET) 1958 but did not reach orbit when the third stage failed to separate. The main purpose of the Vanguard Test Vehicle launchings was systems testing for the launch vehicle and satellite. The program objectives for the satellite were to conduct solar X-ray and space environment measurements from Earth orbit. The IGY Vanguard satellite program was designed with the purpose of launching one or more Earth orbiting satellites during the International Geophysical Year (IGY), which ended on 31 December 1958.

Mission Profile

Vanguard TV-5 was launched on 29 April 1958 at 02:53 UT (28 April, 9:53 p.m. ET) from Cape Canaveral, Florida. The launch proceeded nominally through the second stage burnout 262 seconds after launch. Following this, however, two electric relays malfunctioned and failed to transmit the signal to arm the coasting flight control system, preventing the third stage from separating and firing. The second and third stages reached an altitude of 358 miles and crashed about 1600 miles downrange from the launch site. This concluded the Vanguard Test Vehicle series, the Vanguard missions following this were designated Vanguard Satellite Launching Vehicle (SLV) followed by a sequential number.

Spacecraft and Subsystems

The TV-5 satellite was a 9.75 kg (21.5 lb), 50.8 cm (20 inch) diameter sphere. The shell was composed of magnesium, coated with highly polished silicon monoxide. It had four protruding metal rod antennas. A 108.00 MHz transmitter at 80 milliwatts was designed to provide tracking and telemetry. Power was supplied by mercury batteries. The payload included an instrument to measure solar X-ray emissions in the 1 to 8 Angstrom band and space environment monitors.

Launch Vehicle

Vanguard was the designation used for both the launch vehicle and the satellite. The first stage of the three-stage Vanguard Test vehicle was powered by a GE X-405 28,000 pound (~125,000 N) thrust liquid rocket engine, propelled by 7200 kg of kerosene (RP-1) and liquid oxygen, with helium pressurant. It also held 152 kg of hydrogen peroxide. It was finless, 13.4 m (44 ft.) tall, 1.14 m (45 in.) in diameter, and had a launch mass of approximately 8090 kg (17,800 lbs. wt.).

The second stage was a 5.8 m (19 ft.) high, 0.8 m (31.5 in.) diameter Aerojet-General AJ-10 liquid engine burning 1520 kg (3350 lbs) Unsymmetrical Dimethylhydrazine (UDMH) and White Inhibited Fuming Nitric Acid (WIFNA) with a helium pressurant tank. It produced a thrust of 7340 pounds (~32,600 N) and had a launch mass of approximately 1990 kg (4390 lbs. wt.). This stage contained the complete guidance and control system.

A solid-propellant rocket with 2350 pounds (~ 10,400 N) of thrust (for 30 seconds burn time) was developed by the Grand Central Rocket Co. to satisfy third-stage requirements. The stage was 1.5 m (60 in.) high, 0.8 m (31.5 in.) in diameter, and had a launch mass of 194 kg (428 lbs.). The thin (0.076 cm, 0.03 in.) steel casing for the third stage had a hemispherical forward dome with a shaft at the center to support the satellite and an aft dome fairing into a steel exit nozzle.

The total height of the vehicle with the satellite fairing was about 21.9 meters (72 feet). The payload capacity was 11.3 kg (25 lbs.) to a 555 km (345 mi.) Earth orbit. A nominal launch would have the first stage firing for 144 seconds, bringing the rocket to an altitude of 58 km (36 mi), followed by the second stage burn of 120 seconds to 480 km (300 mi), whereupon the third stage would bring the satellite to orbit. This was the same launch vehicle configuration, with minor modifications, as used for Vanguard TV-3 and all succeeding Vanguard flights up to and including Vanguard SLV-6.

Alternate Names

  • VanguardTV5

Facts in Brief

Launch Date: 1958-04-29
Launch Vehicle: Vanguard
Launch Site: Cape Canaveral, United States
Mass: 9.75 kg

Funding Agency

  • Department of Defense-Department of the Navy (United States)


  • Communications

Additional Information

Questions and comments about this spacecraft can be directed to: Dr. David R. Williams



NameRoleOriginal AffiliationE-mail
[] NASA Logo -