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
Launch Site
Stats
Vanguard
10th
Mission
3rd
Mission of 1959
1959
9th
Orbital launch attempt