BUNKER HILL – It’s called a rocket sled. It’s a Cold War relic that the U.S. Air Force used to test an experimental ejection-rescue system for the B-58 Hustler bomber plane – and it’s the only one of its kind in existence.

And last week, the one-of-a-kind sled was unloaded at the Grissom Air Museum as the newest exhibit documenting the unique history of Grissom Air Reserve Base.

The rocket sled is an obscure piece of military equipment, but Museum Board Member Tom Kelly said the 50-foot sled tells an important story about the base.

That’s because in 1961, then-Bunker Hill Air Force Base was selected as the home to a fleet of brand new supersonic nuclear strike aircraft – the B-58 Hustler.

Kelly said the bomber could fly faster and higher than any Soviet fighter jet of the era, but that presented some serious problems for the three-man crew. Because of the B-58s high-altitude and high-speed performance capabilities, the crew was sure to be killed if they had to eject from the aircraft using a conventional ejection system.

So the Air Force started extensive testing to solve the problem. And the centerpiece of those tests was the rocket sled.

Using the full-size model of a B-58 fuselage mounted on rails built in the desert of New Mexico, engineers would accelerate the sled to supersonic speeds and launch a fully pressurized capsule into the sky.

The capsule had its own oxygen supply to project the airman from Mach-2 wind speeds and 70,000-feet altitudes, where temperatures are 55-below zero.

But instead of putting airmen into the capsule during test runs, the Air Force used bears. That’s right. Sedated black bears were loaded into the capsule as test subjects and launched into the sky over the desert.

“The joke at the time was the worst job in the Air Force was unstrapping those bears after they got ejected,” Kelly said.

Records show two bears suffered minor fractures and bruising during their flights. But all the bears ended up being killed in order for the Air Force to do autopsies to ensure there were no hidden injuries before testing the capsules on humans.

Those tests eventually led to a working ejection system for the B-58 bombers that ended up saving the lives of at least three airmen stationed at Grissom who had to eject from the plane, Kelly said.

Today, there are only eight B-58 Hustlers in existence, and the Grissom Air Museum has one of them. Now, the rocket sled will provide a unique look at how the plane’s new-fangled ejection system came into existence.

Kelly said the sled was formerly on display at the Global Power Museum at Barksdale Air Force Base in Louisiana, which agreed to give it to Grissom as a permanent loan after one of the museum’s volunteers asked if they could borrow it for a display.

“The (Global Power) museum decided that we should have it when we asked for it,” he said. “It’s really quite an honor to get it up here.”

Guyer the Mover of Peru volunteered to drive to Louisiana to pick up the sled and transport it to Grissom. The item arrived recently and was unloaded by a small crane on Feb. 20.

Museum Director Tom Jennings said the sled will be stored behind the museum until a concrete pad can be poured to place it on permanent display in the museum’s airfield, which is home to 24 historic military aircrafts. He said the sled should be on display no later than April.

Once the exhibit is installed, Jennings said, it’s sure to be a big hit with visitors.

“It’s garnered a lot of interest,” he said. “We’ve had a lot of enthusiasm about it. It’s a good item to have here because it helps us tell more of the story of the B-58 pilots and what they trained for and how they prepared for flights.”

Kelly agreed. “People are very excited about this. People have driven all the way to Louisiana just to see it, so to have it up here will really add to our attractions.

“It’s a one-of-a-kind thing and we’re so lucky to have it,” Kelly said. “I think this museum has become the centerpiece for the B-58 exhibits, and I can’t think of a better place than here to have it on display.”

For more information, visit www.grissomairmuseum.com.