NASA's new rocket will get shock absorbers

Two different systems at the top and bottom of the new rocket's first stage should reduce the booster's peak vibrations during flight to what engineers described as a few-seconds-long "jackhammer effect."

The recommended shock absorber system includes a spring and damper system between the Ares I booster's first and second stages, as well as a set of 16 spring-mounted weights in the aft skirt at the bottom of the first stage.

"It's a lot like the shock absorbers on your car," said Steve Cook, Ares project manager at NASA's Marshall Space Flight Center in Huntsville, Ala., in a Tuesday teleconference. "It isolates the vibrations just traveling through the structure, all the way up to the seat."

Without the upgrade, an Ares I rocket and its astronaut crew would be subjected to shaking forces of up to five or six times Earth's gravity (5 to 6 Gs), or about twice the force experienced by shuttle astronauts during launch, according to NASA's early analysis. But with the shock absorbers in place, vibrations in the Ares 1 rocket should be limited to about 0.25 Gs, or one-fourth the force of Earth's gravity, NASA engineers said.

The peak shaking should last just a few seconds near the 115-second mark just after liftoff, said Cook, who sat in a chair-based simulation of the vibration in a NASA test. He compared it to driving a car on the bumpy shoulder of a highway.

"It really doesn't physically bother you," Cook said. "It's just kind of a high vibration."