Historic reactors for atomic airplanes, a concept that never really got off the ground in the 1950s, are being moved to a place where they will go on display next summer.

The Department of Energy said the second of two Heat Transfer Reactor Experiment reactors, designed to provide nuclear power for aircraft, was to be moved over the weekend.The 225-ton reactor was scheduled to be unloaded Monday at the Experimental Breeder Reactor 1 facility in Arco, a decommissioned nuclear plant that has been a tourist attraction for several years.

Two assemblies were built in the 1950s to test the concept of nuclear-powered airplanes. One, the 300-ton HTRE-2, was moved last week. It was designed in a vertical configuration, much the same as most commercial nuclear reactors in this country.

HTRE-3 was built in a horizontal configuration to fit in an airplane. Two aircraft engines were mounted to the assembly and successfully powered by the reactor during a test run.

Scientists and engineers worked on the project for about 14 years, but the program ended with the advent of intercontinental ballistic missiles and the improved defense capabilities they offered.

Much concern was expressed at the time about what would happen if a nuclear-powered aircraft ever crashed, and researchers weren't able to assure full containment without so much shielding that the aircraft never would be able to get off the ground.

DOE said in a news release Saturday the nuclear airplane never flew, but useful information was gained from the program and applied in commercial and defense nuclear areas. Advances were made in metallurgy, fuel elements, reactor theory, synthetic oils, electronics, shielding and nuclear size.

PREMAY, a Canadian contractor with an office at Pocatello, was hired for the move. A special truck with 144 wheels and a capacity of 1,200 tons, is being used.

DOE said the reactors were deactivated and decontaminated and with support from the Smithsonian Institute, will be placed on public display.