Moon rocket designers reflect on their success

It wasn’t a young president’s brash promise that enabled Neil Armstrong and Buzz Aldrin to take those first halting steps on the lunar surface 40 years ago Monday. Nor was it the courage of the astronauts themselves.

The success of America’s big bet in space depended on the ability of young, unheralded engineers to build rocket engines that were both powerful enough and reliable enough to wrench the spacecraft from Earth’s jealous grasp and send it winging to the lunar surface.

The result of their work was the mammoth Saturn V, the largest and most powerful launch vehicle of its time. It was as tall as a 40-story building, with engines that gulped swimming pools worth of fuel every second. Producing 7.5 million pounds of thrust at liftoff, Saturn V was so powerful that during a test at Cape Canaveral, Fla., it rained ceiling tiles on the head of CBS news anchor Walter Cronkite, watching from four miles away.

“What set us apart was our ability to build a very big rocket to get us to the moon,” said Roger Launius, the Smithsonian Institution’s space historian, reflecting on the U.S.’ race with the then-Soviet Union to reach the moon first. “The Russians were never able to do that.”

Three-stage rocket

The rocket that would get us to the moon was composed of three parts, or stages. North American Aviation in Seal Beach, a coastal community south of Los Angeles, built the second stage — plus the astronauts’ command module, scaling up its Downey plant southeast of downtown L.A. to 25,000 employees to do so. Douglas Aircraft in Huntington Beach, near Seal Beach, made the third stage.

The massive engines that would power each of the stages were the responsibility of Rocketdyne in the San Fernando Valley, then a division of North American and now managed by Pratt &Whitney. As NASA management fretted that precious time was ticking away, Rocketdyne’s engineers battled combustion problems and a dangerously faulty start-up sequence on the first-stage engines, and the failure of two second-stage engines in a key test less than a year before Apollo 11’s scheduled launch.

Those engineers were every bit the typical postwar working stiffs. Newly married and raising families, these men set up housekeeping in the fast-growing suburbs and threw themselves into the work of a lifetime.

“Everybody was young,” said Joe Stangeland, a structural specialist who worked on the first-stage F-1 engine. “Anyone over 30 was a veteran. I owned a $13,000 house and spent 16 hours a day working.”

Vanishing generation

Today, those engineers are part of a vanishing generation; the junior members in their 70s.

Stangeland, 73, and two other Rocketdyne vets who played key roles in the development of the Saturn V — Bob Biggs, who worked on the F-1, and Paul Coffman, assigned to the second-stage J-2 engine — recently reflected on the thrill and exhaustion of the moon race.

The space race was inaugurated in May 1961, when President John F. Kennedy Jr. announced that by the end of the decade, the U.S. would land a man on the moon and return him safely to Earth.

It was an audacious gamble. The Soviets held a clear early lead in space. In October 1957, they had launched the first piece of space flotsam, the beeping Sputnik satellite. America’s space program had gotten off to a sputtering start with the failure of its first space rocket, Vanguard, dubbed “Flopnik” by a jeering media.

The nation united behind Kennedy’s bold gamble, investing $25 billion (about $180 billion in today’s dollars) and employing 400,000 workers in 20,000 companies across the United States.

“The Apollo program had a tremendous impact on the United States,” Space Foundation Chief Executive Officer Elliot Pulham said. “It built national pride and, more importantly, it influenced a whole generation of children to study hard to become scientists, engineers and astronauts.”

The Saturn V design called for five first-stage F-1s to burn kerosene for 2.5 minutes, after which five second-stage J-2 rockets, using a brand new fuel, liquid hydrogen, would propel the spacecraft to 15,600 mph and an altitude of 109 miles.

The third stage, consisting of a single J-2 engine, was to burn for 2.5 minutes, placing the craft in a parking orbit around the Earth. Several hours later, the engine would ignite again and burn for six more minutes, setting the linked command and lunar modules on course for the moon at 25,000 miles an hour.

Everything was big

Everything about the Saturn V was big, including its appetite. Fueling it required 89 truckloads of liquid oxygen, 28 trailer-loads of liquid hydrogen, and 27 rail cars full of kerosene.

But envisioning a monster like the Saturn V and making it work were two different things. The greatest challenge was the biggest engine, the F-1. Eighteen feet tall and weighing nine tons, it was designed to be 10 times as powerful as any previous rocket.

“A 10 percent upgrade is significant in engineering terms,” said Biggs, a bearish, bespectacled man of 75. “A factor of 10 puts it in a whole new universe.”

The sheer “bigness” brought on a series of problems, said Biggs, who went to work at Rocketdyne in 1957, fresh out of the Army. The engine was so noisy engineers had to move it to Edwards Air Force Base in the Mojave Desert for testing.

A key problem was the start-up. “They had a design for the starting sequence,” Biggs said. “I did the analysis and told them it was no good. The rocket would probably blow up.”

Biggs’ solution was to slow down the launch sequence. That gave the Saturn V its characteristic feline look, as it seemed to crouch and gather itself for five seconds after ignition before lifting off the launch pad.

Combustion woes

The next problem — and the biggest — was combustion instability. The F-1’s central chamber was so large that the fuel and oxidizer mixed at different rates in different places, causing the mixture to slosh around, setting off tremors that, unless stopped, shook the engine apart. The problem lingered for two years, Biggs recalled.

Brainerd Holmes, then head of the National Aeronautics and Space Administration’s Office of Manned Spaceflight, urged engineers to consider scrapping the design altogether.

As it turned out, Soviet scientists were running into the same problem on their moon rocket, the super-secret N-1. Their solution was to discard the idea of using a few large engines on the first stage, substituting 30 smaller engines. But that created problems too, such as synchronizing all those motors.

While other problems, some political, hampered the Soviet program, “It was mostly materials science,” Launius said, that defeated that nation’s efforts to reach the moon first. “They just didn’t have the capability to make their engines work.”

After 15 redesigns, including changing the way the fuel and oxidizer were fed into the engine and the installation of baffles to regulate flows, Rocketdyne was finally able to tame its huge engine. “One day, it was suddenly stable,” Biggs said.

Next up was a problem with the impeller on the liquid oxygen pump. Individual blades that stirred the fuel and oxidizer kept breaking off and starting fires that burned out the pump. “We had a half-dozen blowups,” Biggs said.

The F-1s performed flawlessly on every one of the Saturn V’s 13 manned and unmanned launches from 1967 to 1973. The vehicle sent a dozen astronauts to the surface of the moon, as well as scientific equipment and hardware, including three 10-foot-long lunar rovers.

Just as the engineers managed to solve the problems with the first-stage engines, trouble developed with the second-stage J-2s. Two minutes into a test flight on April 4, 1968, a little more than a year before the launch of Apollo 11, two of the J-2s shut down early. Pieces of the third stage fell off. The craft was supposed to circle the moon and return, but it never got out of Earth’s orbit.

This event caused consternation at NASA’s highest levels.

Paul Coffman headed up one of two teams assigned to figure out what went wrong — and fast.

The failure was traced to a coupling on a flexible fuel line, which workers replaced with stainless steel pipe. As a result, the flight of Apollo 8 in December 1968 went off as scheduled. The crew of Frank Borman, William Anders and James Lovell Jr. orbited the moon 10 times in 20 hours, becoming the first humans to see the far side of the moon.

Resounding success

The mission was a resounding success, at last putting to rest doubts about the Saturn V.

Seven months later, Apollo 11 roared off the launch pad at Kennedy Space Center. Biggs was home in L.A. on the evening of July 20, watching the same muddy image of Armstrong’s first small step with the rest of America.

“The whole neighborhood turned out,” he said. “I remember everybody was out on the sidewalk.”

Coffman was on his way back from Northern California, where he had raced his Triumph Spitfire sports car. He stopped every hour or so at bars along the way to check on the status of the spacecraft.

“I was most of the way home before I saw that grainy image (of Armstrong) on TV. I think it was in Fresno,” Coffman said. “The feeling was just euphoria.”

The Soviet N-1 flew just four times, all unmanned. It blew up every time. The end came in 1972, when the last test rocket disintegrated 25 miles above Earth due to the same combustion instability problems that had bedeviled the Saturn V. The Soviets quietly disbanded their moon-landing program.

Today, Biggs, Stangeland and Coffman still work in various capacities at Rocketdyne. Stangeland is a consultant. Biggs’ title is principal engineer. They realize they are part of a departing generation of lunar pioneers, but they are not quite ready to shuffle off into history.

At 74, Coffman is at work on a new version of the J-2, a key part of the Ares 1 rocket being built to carry astronauts back to the lunar surface by 2020.

“How can you have more fun and feel more useful than to participate in the second version (of the space race)?” Coffman said, laughing.

Talk to us

> Give us your news tips.

> Send us a letter to the editor.

> More Herald contact information.

More in Local News

LifeWise local co-directors Darcie Hammer and Sarah Sweeny talk about what a typical classroom routine looks like on Monday, April 14, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
Everett off-campus Bible program draws mixed reaction from parents

The weekly optional program, LifeWise Academy, takes children out of public school during the day for religious lessons.

Protesters line Broadway in Everett for Main Street USA rally

Thousands turn out to protest President Trump on Saturday in Everett, joining hundreds of other towns and cities.

An EcoRemedy employee checks a control panel of their equipment at the Edmonds Wastewater Treatment Plant on Thursday, April 17, 2025 in Edmonds, Washington. (Olivia Vanni / The Herald)
Edmonds launches technology to destroy PFAS

Edmonds is the first city in the country to implement… Continue reading

Over a dozen parents and some Snohomish School District students gather outside of the district office to protest and discuss safety concerns after an incident with a student at Machias Elementary School on Friday, April 18, 2025 in Snohomish, Washington. (Olivia Vanni / The Herald)
Parents protest handling of alleged weapon incident at Machias Elementary

Families say district failed to communicate clearly; some have kept kids home for weeks.

Irene Pfister, left, holds a sign reading “Justice for Jonathan” next to another protester with a sign that says “Major Crimes Needs to Investigate,” during a call to action Saturday, April 12, 2025, in Arlington. (Aspen Anderson / The Herald)
Arlington community rallies, a family waits for news on missing man

Family and neighbors say more can be done in the search for Jonathan Hoang. The sheriff’s office says all leads are being pursued.

Mary Ann Karber, 101, spins the wheel during Wheel of Forunte at Washington Oakes on Tuesday, April 1, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
Lunch and Wheel of Fortune with some Everett swinging seniors

She’s 101 and he’s 76. At Washington Oakes, fun and friendship are on the menu.

Jordan Hoffman-Nelson watches the store cameras for a couple hours each day, often detecting 5 to 10 thefts in a single sitting. (Aspen Anderson / The Herald)
At a Lynnwood thrift store, rising shoplifting mirrors larger retail crime surge

Employees at Bella’s Voice remain alert for theft on a daily basis. They aren’t the only ones.

Connect Casino Road Director Alvaro Gullien speaks at an Everett City Council meeting to share community thoughts regarding affordable housing and preventing displacement of those that live along Casino Road on Wednesday, April 16, 2025 in Everett, Washington. (Olivia Vanni / The Herald)
How will Everett’s comprehensive plan work in Casino Road?

Residents in the diverse, tight-knit neighborhood want “Investment without displacement.” The city’s plan will help achieve that, staff say.

Henry M. Jackson High School’s FIRST Robotics Competition championship robotics Team 2910 Jack in the Bot on Thursday, April 24, 2025 in Mill Creek, Washington. (Olivia Vanni / The Herald)
Mill Creek robotics team celebrates world championship win

The team — known as “Jack in the Bot” — came in first place above about 600 others at a Texas world championship event last week.

Trees and foliage grow at the Rockport State Park on Wednesday, April 3, 2024 in Rockport, Washington. (Annie Barker / The Herald)
Washington Legislature approves hiking Discover Pass price to $45

The price for a Washington state Discover Pass would rise by $15… Continue reading

The Washington state Capitol on April 18, 2025. (Photo by Jacquelyn Jimenez Romero/Washington State Standard)
Parental rights overhaul gains final approval in WA Legislature

The bill was among the most controversial of this year’s session.

Snohomish firefighters appeal vaccine suspensions to Ninth Circuit

Despite lower court’s decision, eight men maintain their department did not properly accommodate their religious beliefs during COVID.

Support local journalism

If you value local news, make a gift now to support the trusted journalism you get in The Daily Herald. Donations processed in this system are not tax deductible.