We are proud of our connection to history and such a monumental event as the Apollo 11 moon launch and landing. It’s the stuff of heroes and legends. For most of our employees, the moon landing was learned about through teachers, text books and parents. But for a few engineers during the race to space, the stuff of legends is part of their personal history and an honorable memory.
Working with IBM (known then as International Business Machines), engineers at LORD Corporation designed anti-vibration mounts to secure fragile computer elements within the Apollo 11 Instrument Unit (IU). This huge ring, measuring three feet high and almost 22 feet in diameter, weighed more than 4,000 pounds and was jettisoned prior to entering orbit around the moon.
The engineers working on the IU nicknamed it “the brain” because it housed the guidance, navigation and control equipment used to steer the Saturn V rocket through its Earth orbits and into the final translunar injection maneuver. At that point, the Apollo Command and Lunar Modules on-board guidance systems assumed control.
The launch vehicle digital computer and data adapter within the IU performed the navigation and guidance computations and the flight control computer converted any generated attitude errors into control commands. Calculations were made about once each second throughout the flight.
Planning for a Controlled Explosion and Massive Vibration
Launching a rocket exposes all this delicate equipment to excessive vibration levels. To leave the Earth’s atmosphere, the 50-ton spacecraft was propelled into space at 6,000 miles per hour by 7.5 million pounds of thrust. The Saturn V is the world’s most powerful rocket to date. We’ve all seen the launch video—the incredible shaking and immense fire, smoke, and subsequent jettisons as staged rockets exposed critical elements to even further explosions and vibrations. The rocket almost shook itself apart during the Apollo 6 test flight in 1968.
Elastomeric mounts designed and manufactured by LORD in Erie, Pa., were used to secure sensitive electronics on the IU. An additional custom isolator was specifically designed to protect mission-critical switch selectors that controlled firing the separation of the rocket stages.
Our Engineer Jeff Ley explains, “Our parts provided vibration isolation for the sensitive electronics. There were some digital computers that controlled the brains of the rocket and guidance units that are very critical. Rocket launches are a controlled explosion, these electronics are very fragile, and they need to perform – or the rocket doesn’t go where it’s supposed to.”
If these computers are not sufficiently protected, it would be a disaster – loss of communications, and loss of flight control with the astronauts unable to take control of the rocket prior to entering lunar orbit.
Editor’s Comment: Ley notes that during the Apollo 12 launch (November 14, 1969), the rocket ship was struck by lightning twice. The digital computer and instrument ring had to drive the rocket because ground control lost telemetry. That’s how critical the instrument ring is, and it did its job—the rocket ship was protected from the lightning strike but the electronics on the ground were knocked out.
Planning for the Unknowns of Space
Citing the mount designs as a major technical achievement for LORD regarding vibration isolation, Ley explains that the elastomeric compound had to also function in the zero atmosphere of space.
“The fact that we can help these delicate and sensitive electronics survive a rocket blast is a huge milestone because these are vibration levels unlike anything we see anywhere else,” continues Ley. “Also, our materials have to function once they’re up in space and cannot lose any gases or volatiles.”
Many elastomeric materials (rubber, silicone, etc.) used in vibration isolators can “outgas” after they are cured. Volatile material used as ingredients in the elastomer formulation or cure process can migrate to the surface and be released over time. This is often not desirable for space application electronics where there is no pressurization or atmosphere, or if optics are involved. To solve this, special materials or bake processes in the cure of the elastomer are used to force out the gasses so this does not happen in space. We have used these materials and vacuum bake processes to meet these requirements for many years.
When the application requires it, our materials continue to go through extensive testing and extra processing (i.e., vacuum bake) to make sure they meet all the outgassing and specific material requirements by NASA.
“Thank You” to Our Heroes
2019 marks the 50th anniversary of the Apollo 11 moon landing. LORD Corporation salutes the thousands of heroic men and women involved in getting our astronauts to the moon and back again safely. Whether they were part of mission control, designed a portion of the rocket or module, or helped to manufacture seemingly inconsequential parts – each played a significant role and contributed to the history we celebrate. We humbly thank you.