The mighty Saturn V, the rocket that took humans to the moon, remains the tallest, heaviest, and most powerful rocket ever brought to operational status (as of 2018). It was used by NASA between 1967 and 1973. It was powered by five Rocketdyne F-1 engines. With a thrust of 1,746,000
Today, private companies like SpaceX, Blue Origin, and space agencies like NASA trying to build powerful rockets in order to reach Moon and Mars. But, we’ve already built a rocket which took us to the moon, why don’t we simply remake it (and the engines)? In the video below, Youtube user Curious Droid answers this question.
In a nutshell, we can’t (and we shouldn’t) remake Apollo Program’s mighty Rocketdyne F-1 engines because:
- The ultra-talented and experienced engineers who built the Rocketdyne F-1 engine were retired or long dead – and some of the crucial knowledge, skills, and experience were long gone with them.
- Many of those skills and techniques which was used to build F-1 engines are no longer in use. So we simply don’t have the people and skills that can make them in the same way anymore.
- With the help of powerful computers and new technologies, we can do a better job today (if we can find enough money to do that). With the examination of Rocketdyne F-1 engines from museums and storage, today’s engineers did discover enough to create a new F-1B engine should it ever be built. Using modern computing modeling and manufacturing techniques, the new engine could not only be more efficient, it would be just as powerful as the updated but unflown F-1A at 1.8 million pounds of thrust. More importantly, it would reduce the number of manufactured parts from around 5,600 to just 40! And while increasing its reliability and decreasing costs in the process.
I would recommend you to subscribe to Curious Droid’s channel if you haven’t already.
Related: Saturn V Rocket (Documentary)
The mighty and huge Rocketdyne F-1 Engine
In the image above, German (and, later, American) aerospace engineer and space architect Dr. Wernher von Braun (March 23, 1912 – June 16, 1977) standing by five Rocketdyne F-1 Engines. A pioneer of America’s space program, Dr. von Braun stands by the five F-1 engines of the Saturn V Dynamic Test Vehicle on display at the U.S. Space & Rocket Center in Huntsville, Alabama.
Designed and developed by Rocketdyne under the direction of the Marshall Space Flight Center, a cluster of five F-1 engines was mounted on the Saturn V S-IC (first) stage. The engines measured 19-feet (5.8 meters) tall by 12.5-feet (3.8 meters) at the nozzle exit and burned 15 tons of liquid oxygen and kerosene each second to produce 7,500,000 pounds of thrust. The S-IC stage is the first stage, or booster, of a 364-foot long (110.9 meters) rocket that ultimately took astronauts to the Moon.
The Rocketdyne F-1 engine had roots outside NASA, born as an Air Force program developed by the aerospace firm Rocketdyne in 1955. NASA inherited it during a transfer of projects, conducted its own feasibility studies and awarded Rocketdyne a follow-on contract to step up work on the gargantuan propulsion system not long after NASA’s formation, in 1960.
Each second, a single Rocketdyne F-1 engine burned 5,683 pounds (2,578 kg) of oxidizer and fuel: 3,945 lb (1,789 kg) of liquid oxygen and 1,738 lb (788 kg) of RP-1, generating 1,500,000 lbf (6.7 MN; 680 tf) of thrust. This equated to a flow rate of 671.4 US gal (2,542 l) per second; 413.5 US gal (1,565 l) of LOX and 257.9 US gal (976 l) of RP-1.
During their two and a half minutes of operation, the five F-1s propelled the Saturn V vehicle to a height of 42 miles (222,000 ft; 68 km) and a speed of 6,164 mph (9,920 km/h). The combined flow rate of the five F-1s in the Saturn V was 3,357 US gal (12,710 l) per second, or 28,415 lb (12,890 kg). Each Rocketdyne F-1 engine had more thrust than three Space Shuttle Main Engines combined.
A bullet-proof (actually bomb-proof!) design
The engine was designed to the human-rated safety concept, which requires that it be dynamically stable. If any of the engine’s systems are disturbed from any source, the system must automatically overcome the disturbance and return to stable operation.
To prove the F-1’s ability to stabilize, a method for creating artificial disturbance was introduced by detonating a bomb inside the combustion chamber near the injector face. Different injector designs were evaluated according to their ability to recover quickly from such disturbances. The result is an injector design in the present production configuration of the F-1 engine that has proved to be very quickly self-stabilizing in response to induced disturbances.
The powerful roar of Rocketdyne F-1 engines
Walter Cronkite (November 4, 1916 – July 17, 2009), covering the Apollo 4 launch for CBS News later admitted he was “overwhelmed” by the power of the Saturn V rocket and the emotion of the moment. His on-air description was delivered without his usual poise and reserve as he yelled above the launch noise into his microphone.
… our building’s shaking here. Our building’s shaking! Oh, it’s terrific, the building’s shaking! This big blast window is shaking! We’re holding it with our hands! Look at that rocket go into the clouds at 3000 feet! … you can see it… you can see it… oh the roar is terrific!Walter Cronkite, Broadcast of Apollo 4 launch