Engine That Almost Launched Apollo 8 Moonshot Found 40 Years Later

Five seconds before the first men left Earth for the Moon on Dec. 21, 1968, the rocket they were riding ignited its first stage's five engines. They were the first astronauts to launch atop the Saturn V, and that day 40 years ago at 7:51 a.m. EST was the first time those particular five F-1 engines had fired together.

For the Apollo 8 crew of Frank Borman, James Lovell and Williams Anders, for the next 150 seconds, those engines needed to work for their mission - to circle the Moon - to be possible.

And work they did; despite having to burn 2.4 seconds longer than planned to make up for an underperformance, the five 19-foot tall, Rocketdyne-built F-1 engines - each more powerful than all three of today's space shuttle main engines combined - propelled Apollo 8 to 40 miles above the Earth. Their work done, the first stage was jettisoned and allowed to fall back and sink to the ocean floor some 350 miles off the coast.

Borman, Lovell and Anders, with the help of their Saturn V's upper stages and Apollo 8 command module would of course succeed, entering lunar orbit on Christmas Eve in 1968, making history as the first to enter the gravitational field of another celestial body. Their flight would be hailed as one of the boldest in all of human history.

The Saturn V rocket used to launch their adventure has long since vanished, having served its purpose, although the third stage continues to travel unseen in heliocentric orbit about the Sun. All that remains of their journey is the command module, on display at the Museum of Science and Industry in Chicago, Illinois.

There exists however another component that was almost part of the Apollo 8 launch vehicle. Lost in plain sight for years, it was recently rediscovered just in time for Apollo 8's 40th anniversary.

The (not-so-little) engine that couldn't

After being assembled at the Michoud Assembly Facility in Louisiana, test fired at NASA's Marshall Space Flight Center in Alabama and shipped back to New Orleans for further testing, Apollo 8's Saturn V first stage departed by barge to Florida on Dec. 23, 1967. It arrived at the Kennedy Space Center four days later.

Normally - and for the remainder of the Apollo program - the engine configuration that arrived at the cape would be the contingent that flew when launched. But that wasn't to be for Apollo 8's first stage.

"A problem was discovered in one of the engines," Alan Lawrie, author of "Saturn" and most recently, "Saturn 1/1B", explained to collectSPACE.com. A leak in a fuel pump seal was found in one of the outboard engines, requiring its replacement.

"The engine was taken off the stage just seven months before eventual launch and replaced by a spare engine," said Lawrie. "When Apollo 8 lifted off the five F-1 engines had never been fired together before because of this late replacement."

The rejected F-1, known by its serial number F-4023, was returned to Rocketdyne in Los Angeles for servicing. First assembled in 1964 as the 23rd flight-standard F-1 engine, F-4023 was repaired and again declared flight-worthy less than three months before Apollo 8 launched.

"However, the engine was never re-allocated to another stage," said Lawrie. "Instead, it was shipped to Michoud where it was used to verify the effects of long term storage on F-1 engines. It remained at Michoud for over 20 years."

In 1990, the engine was inspected by Rocketdyne before it was moved to Alabama, moving between the Marshall Space Flight Center and U.S. Space and Rocket Center.

"In the intervening period, the historical link between this engine and its planned mission was lost," Lawrie shared...

Continue reading at collectSPACE.com to learn how and where the lost engine was found.

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