Vanguard SLV-6

Launch Failure

Liftoff Time (GMT)

20:16:00

Monday June 22, 1959

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Mission Details

Launch Notes

The second stage helium control bottle valve failed to open properly at engine start. Tank and chamber pressures rapidly decayed during second stage burn, and 40 seconds after engine start, the helium bottle ruptured due to pressure buildup. The third stage then separated and ignited, driving itself and the satellite into the Atlantic Ocean 300 miles downrange.

Vanguard SLV-6

The Vanguard Radiation Ballance satellite was a magnesium alloy sphere (20 inches in diameter) intended to measure the solar-Earth heating process which generates weather.

Medium Earth Orbit

1 Payload

10 kilograms

Rocket

Retired
Vanguard

Active 1957 to 1959

United States Navy logo

Agency

US Navy

Rocket

Height: 23m

Payload to Orbit

LEO: 10 kg

Liftoff Thrust

135 Kilonewtons

Stages

3

Launch Site

LC-18A

Cape Canaveral SFS, Florida, USA

Fastest Turnaround

29 days

Stats

Vanguard


10th

Mission

3rd

Mission of 1959

1959


9th

Orbital launch attempt