16 July 1969, 16:16:16 UTC, T + 02:44:16.2

This 1966 illustration depicts the J-2 engine of the S-IVB third stage firing to send the Apollo spacecraft to the Moon. (NASA)
This 1966 illustration depicts the J-2 engine of the S-IVB third stage firing to send the Apollo spacecraft to the Moon. (NASA)

16 July 1969: At 16:16:16 UTC, T+02:44:16.2, the Apollo 11 S-IVB third stage engine reignited for the Trans Lunar Injection maneuver.

One of the necessary features of the Rocketdyne J-2 engine was its ability to restart. The third stage was first used to place the Apollo 11 spacecraft into Earth orbit and was then shutdown. When the mission was ready to proceed toward the Moon, the J-2 was re-started. Using liquid hydrogen and liquid oxygen for propellant, Apollo 11′s S-IVB burned for 5 minutes, 41.01 seconds, with the spacecraft reaching a maximum 1.45 Gs just before engine cut off. The engine was shut down at T+02:50:03.03. Trans Lunar Injection was at 16:22:13 UTC.

© 2015, Bryan R. Swopes

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2 thoughts on “16 July 1969, 16:16:16 UTC, T + 02:44:16.2

  1. Shouldn’t it read either “restart” or “start a second time?” “restart a second time” implies that it restarts twice.

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