ATLANTA ? A massive Russian cargo plane roared into Atlanta on Friday to pick up one of the world's largest concrete pumps, which has been retrofitted to pour water on a Japanese nuclear power plant stricken by an earthquake and tsunami.

The 190,000-pound (86,180-kilogram) pump designed by Wisconsin-based Putzmeister America Inc. comes mounted on a 26-wheel truck. Its extendable boom can reach more than 200 feet (60 meters), and can be operated 2 miles (3 kilometres) away by remote control, making it possible to shoot water into hard-to-reach places at the Fukushima Dai-ichi nuclear power plant in Japan.

If necessary, the pump could also entomb a damaged nuclear reactor in concrete. After a 1986 disaster, Putzmeister sent 11 pumps to pour concrete over parts of the Chernobyl nuclear plant in Ukraine.

"Our whole company feels hopeful that our equipment can be used to make a difference in helping solve the problem," Putzmeister America CEO Dave Adams said while watching the plane arrive.

Japanese authorities have struggled to cool the plant's reactors after a March 11 earthquake and tsunami knocked out its backup cooling systems. The facility has been rocked by explosions, spewed radiation and may have suffered a partial meltdown of its nuclear fuel.

A Putzmeister official in Japan contacted the Tokyo Electric Power Co., which operates the crippled reactors, after watching helicopters and fire trucks struggle to spray water onto the plant. The company managed to reroute a smaller Putzmeister pump to the power plant that had been destined for Vietnam.

A dozen workers used it to pump 150 tons of seawater into one of the reactor's spent-fuel pools in three hours, a result that prompted the utility to request more booms.

Moving such a large pump required hiring a Russian Antonov? N-124 cargo jet, one of the world's largest. After landing in Atlanta, the towering plane taxied to a stop near the truck. The plane's nose lifted, revealing a ramp that extended as if the aircraft had stuck out a green, metal tongue.

Once the ramp was fully constructed, a driver steered the pump truck into the plane.

That pump and another picked up at Los Angeles International Airport are scheduled to depart Saturday. The pumps were bought by the Japanese utility for about $2 million each, and the utility is paying for transportation costs.

Putzmeister America's parent company in Germany has already sent a smaller pump and plans to send another.