@Mark Ollig
The Saturn project was begun Aug. 15, 1958, by the Army Ballistic Missile Agency (ABMA) to develop heavy-lift launch vehicles.
ABMA was transferred to the National Aeronautics and Space Administration (NASA) July 1, 1960, which then became NASA’s Marshall Space Flight Center.
Dr. Wernher von Braun, who developed the V-2 missile during WWII, played a key role in the development of what became the Saturn V rocket.
Today, 62 years ago, NASA launched the uncrewed Saturn I SA-4.
The Saturn-Apollo 4 (SA-4) flight was designed to assess the rocket’s guidance systems, engine redundancy and performance, structural integrity, and ability to handle an engine failure during flight.
At 2:11 p.m. CST (Minnesota time), March 28, 1963, NASA launched the uncrewed Saturn I SA-4 (Saturn-Apollo 4) rocket from Cape Canaveral Launch Complex 34 (LC-34).
This fourth launch of a Saturn I vehicle was the last in the initial testing phase focused on the first stage.
According to the Apollo Program Summary Report, the rocket stood about 162 feet tall, and the total launch vehicle weight, including its dummy upper stages, was about 1,124,000 pounds.
The SA-4 mission was designed as a single-stage working rocket with a dummy second stage to evaluate the performance of the first stage (S-I).
This stage was engineered to generate around 1,500,000 pounds of thrust.
The S-IV “dummy” second stage served primarily for aerodynamic studies and produced no thrust.
Engine No. 5, in what was called an “engine-out” operation, was intentionally shut down 100 seconds after liftoff, with its fuel redistributed to the seven remaining engines.
The flight continued without issues, as the other engines burned two seconds longer to compensate for the loss of Engine No. 5.
This engine-out operation allowed engineers to confirm the SA-4 rocket’s stability and trajectory by using the remaining engines to counteract the loss of thrust from one engine.
As the rocket ascended, it passed through maximum dynamic pressure, showing no signs of failure or stress.
The SA-4 flight provided data on engine redundancy, aerodynamics, and structural behavior.
Engineers fitted the dummy SA-4 S-IV stage with camera pods and test fairings (structures reduce drag) to study future Saturn rocket configurations.
The Saturn I SA-4 obtained a peak velocity of 3,660 mph and reached an altitude of approximately 80 miles before returning to Earth 15 minutes later, where it splashed in the Atlantic Ocean.
The mission tested the spacecraft’s retrorocket system for future stage separation, structural stability, and guidance during engine failure.
The flight also aided the development of the Saturn V rocket for crewed lunar missions.
The Saturn I SA-4 rocket’s first stage featured eight RP-1 (Rocket Propellant-1, a highly refined form of kerosene) and liquid oxygen engines.
These engines directly contributed to the design and engineering of the larger and more advanced engines used in later Saturn rockets, including the Saturn V.
The Apollo 1 mission, intended as the first crewed Apollo flight on a Saturn IB rocket, was tragically never launched Jan. 27, 1967.
A fire in the command module during a launch rehearsal test at Cape Canaveral killed astronauts Gus Grissom, Ed White, and Roger Chaffee.
After the Apollo 1 fire, the command module was totally redesigned using a mixed oxygen-nitrogen atmosphere. The crew cabin was reinforced, improved wiring was installed, and a redesigned hatch was added for safer crew exits.
NASA’s powerful new Saturn V rocket’s inaugural uncrewed launch, designated Apollo 4 and referred to as SA-501, took place Nov. 9, 1967, and was deemed a success.
Apollo 7, the first crewed mission aboard the Saturn IB rocket, was launched Oct. 11, 1968.
The Saturn IB’s first stage used eight H-1 engines to produce approximately 1.6 million pounds of thrust at liftoff.
It carried three astronauts who orbited the Earth 163 times more than nearly 11 days before returning to the Atlantic Ocean.
Commanded by astronaut Walter Schirra, Apollo 7 thoroughly tested the Apollo command module to ensure its reliability and readiness for future crewed missions to the moon.
Apollo 8, commanded by astronaut Frank Borman, was launched Dec. 21, 1968, using the Saturn V rocket.
At launch, the Saturn V was 363 feet tall, weighed about 6.2 million pounds, and produced 7.6 million pounds of thrust from its F-1 engines in the first stage.
Apollo 8 was notable as the first crewed mission to orbit the moon. It completed 10 orbits before safely returning to Earth.
NASA launched Artemis I, an uncrewed mission to the moon, Nov. 16, 2022, using the 322-foot-tall Space Launch System (SLS) Block 1 rocket, which weighed nearly six million pounds.
The SLS’s four RS-25 engines produced 8.8 million pounds of thrust for eight minutes at launch.
The Orion Crew Module, containing a human dummy, reached the vicinity of the moon on Nov. 21, 2022.
Sixty-two years ago, the Saturn I SA-4 rocket launch paved the way for Apollo 11’s “one giant leap for mankind.”
Watch the launch at https://bit.ly/4kTcTK4.
