The Saturn V rocket, a symbol of human achievement, stands tall not just because of its physical stature but also due to the intricate welding that holds it together.
While astronauts like Neil Armstrong and Buzz Aldrin are celebrated for their lunar feats, the welders behind the scenes played a pivotal role in ensuring the rocket’s integrity and safety. This article delves into the complexities of welding rockets, highlighting the expertise and innovations that made the Apollo missions possible.
Neil Armstrong and Buzz Aldrin are the heroes of NASA’s mission to the Moon. But the insane task of building a rocketship often gets overlooked. It’s incredible to realize the amount of welding, expertise, and innovation that went into getting the astronauts off the ground.
The welds had to pass a rigorous inspection to “man-rate” the Saturn V vehicle for human-crewed flights. The job became known for a maddening cycle of “cut-and-try” operations.
Astronauts and an inferno of over 5,000 degrees are only separated by a few inches. The Apollo astronauts would wait with tremendous anticipation for a thousand seconds as their spaceship re-entered back into the atmosphere.
Because of the extensive speeds of the rocket, even friction caused by air molecules would be enough to evaporate unprotected skin in an instant. And this is just a few minutes of a several-day mission where a single weld could have destroyed history as we know it.
During the 1960s, America was locked in a space race with Russia. The possibilities of space travel seemed limitless. However, going to space proved a daunting task. Weight was a big issue.
Every pound carried to low orbit costs more than $10,000 in today’s money. And this meant rivets were quickly out of the picture. Wernher von Braun once said, “I had an awfully uneasy feeling, you know,”; “every time we talked to the Houston people, the damn LEM [lunar excursion module] had gotten heavier again.”
Therefore, NASA’s rockets and spacecraft would have to be welded. So, to keep the construction light, the Saturn V was designed with metal panels that got thinner as you moved toward the top of the rocket. At the time, welding together materials of differing thicknesses was hard.
The welds also had to pass a rigorous inspection to “man-rate” the Saturn V vehicle for human-crewed flights.
Moreover, adding to the stress of the situation, the nation’s eyes were glued to the TV when America attempted to get to the lunar surface.
One single bad weld could cause a catastrophic failure. A faulty problem with the wiring in the Apollo 1 mission led to a fire, killing all three astronauts, Gus Grissom, Edward H. White, and Roger B. Chaffee, suspending the Apollo Program for an extended amount of time.
So, if you ever thought your boss was a stickler for accuracy, he’d be a kitty cat compared to what the early space rocket welders faced.
The welds also had to pass a rigorous inspection to “man-rate” the Saturn V vehicle for human-crewed flights. The difficulties faced by welding technicians and engineers were challenging.
In terms of the nearly perfect welds required for the stages, weld passes of many dozen centimeters were deemed possible (though highly difficult) within the state of the art. The requirements for the S-IC and S-II required nearly perfect welds of several dozen meters.
The job became a maddening cycle of “cut-and-try” operations. The long welding runs created unmanageable distortions in large-circumference cylinders.
Further difficulties included coping with the varying thickness of pieces joined by the welding pass; alignments of the components and quality requirements for the integrity of welded seams produced still more revisions to operational manuals. Experienced and very skilled welders had to be taught the new techniques through on-the-job instructional classes led on-site by the contractor.
Through construction, it was viewed as almost impossible to weld a few centimeters at once successfully, and anything less than perfect had to be redone. Usually, warpage, after many attempts, would cause the piece to become unusable, and the entire sections would have to be redone. Through the meticulous agonizing revisions, the rules on welding were completely rewritten.
Because of the gigantic size of the Saturn V, many of the major structural components need to be fabricated by joining smaller parts or segments. Gas tungsten-arc (GTA) and gas metal-arc (GMA) processes have been used extensively for the fabrication of fuel and oxidizer tanks. For example, – one S-IC vehicle has over 3,000 feet of welds.
Welding Techniques Joint thicknesses of fuel and oxidizer tanks range from 1/8 to 1 inch. Welding was done with gas tungsten arc and gas metal-arc processes using helium and argon, respectively, as the shielding gases. Type 4043 and 2319 filler wires 1/16 inch in diameter were used for welding 2014-T6 and 2219-T87 bare plate, respectively.
The welding between the transition ring and cylindrical section is probably the most critical in the S-IC stage. Three vertical joints are automatically gas metal-arc welded to join three forged and rolled billets. During the final assembly of the tanks, the transition ring is joined to the cylindrical section by a gas metal-arc or gas tungsten-arc weld made from both sides in the horizontal position.
The minimum ultimate tensile strength of butt welds was set to be 35,000 psi for alloy 2219-T87 and 38,000 psi for alloy 2014-T6. All butt welds were 100% inspected radiographically with 2% sensitivity. If flaws are detected, and unfortunately, they often are, repairs are made either manually or by mechanized equipment.
One of NASA’s best welding engineers was a woman.
In the early days, welding machines were not designed to combine plates of varying thicknesses. Apollo Program‘s engineers ended up taking apart their machines and rebuilding them entirely, creating some of the mechanisms that today’s welding machines still use today.
Because any contaminant could make a weld fail inspection, unique portable rooms were designed to encompass the welder. All particles from the welding would be forced out of the air with a special pressurization system.
Also, the rules dictating the social norms were rewritten for NASA’s welders. Moreover, one of NASA’s best welding engineers was a woman. Her name was Margaret Brennecke.
And at the time, a woman in such a high position was somewhat of an oddity. But Margaret’s extensive skill set and irreplaceable expertise made her a crucial part of the rocket construction. Margaret W. “Hap” Brennecke (1911–2008) was a metallurgist. She was responsible for selecting which materials and techniques should be used for the rockets. Brennecke’s primary contribution was to craft the cryogenic fuel tanks.
She was the first female welding engineer to work in the Materials and Processes Laboratory at NASA’s Marshall Space Flight Center, contributing to the Saturn rocket program. She often used her nickname of “Hap” rather than her real name.
She did that so others wouldn’t automatically dismiss her reports upon seeing a female name. This led to others calling her “Miss Hap,” which eventually became “Mishap,” a joke that the safety inspector did not enjoy.
When the Apollo 11 mission, with Neil Armstrong and Buzz Aldrin, finally touched down, the rest of America saw mission control astronauts and watched presidential speeches. But they didn’t see thousands of the world’s best welders struggling with an almost impossible mission to create the perfect weld. Then, take a quick break for lunch and do it all over again.
Following its invention, the art of welding has become an essential part of every historical landmark. And that’s not changing anytime soon. The welding machines have gone a long way from the first Apollo rocket missions. New inventions and technology in new welding machines have made producing the perfect bead a much simpler task than during the Apollo Program.
Dive into “The Complete Guide to the Apollo Program,” your ultimate source for everything about NASA’s historic Apollo lunar missions. Discover key players, groundbreaking technology, and mission milestones all in one place.