MOSCOW, Russia (CNN) ## The U.S. Navy says it is sending a crew to Russia's Pacific Coast to rescue seven Russian sailors trapped in a mini-submarine.
The rescue effort is a race against time because the seven sailors are believed to have less than 24 hours of oxygen left.
The AS-28 mini-submarine, itself a rescue vessel, ran into trouble on Thursday when it became snagged by fishing nets and some sort of cable during a military exercise off the Kamchatka peninsula.
The sailors cannot swim to the surface nor can divers reach the vessel because it is too deep at 190 meters (623 feet) below the surface, according to Russian Navy spokesman Capt. Igor Dygalo.
The situation is different to the Kursk submarine disaster of August 12, 2000 in which the Russian authorities rejected offers of help.
This time Russia swiftly requested assistance from the United States and Japan. Britain has also offered help and is airlifting rescue equipment.
A high-level overnight meeting of Naval officials in Hawaii decided to send a contingent of 30 U.S. sailors and two unmanned rescue vehicles called Super Scorpios to the Pacific waters, U.S. Navy sources told CNN.
The sailors and the rescue vehicles will be loaded onto an Air Force C-5 and will be departing from the San Diego North Island Naval Station. Departure will be as soon as 10:45 a.m. PT (1745 GMT) on Friday.
The crew and the vehicles will then be taken to a Russian surface ship, from which the crew will drop the Super Scorpios over the side.
They will try to untangle the mini-sub from the fishing nets, the Navy sources said. Dygalo also said Britain was providing unspecified assistance.
But as the operation intensified on Friday, naval officials revised earlier assertions that the crew had air to last several days.
"There is air remaining on the underwater apparatus for a day ## one day," Dygalo said Friday on state-run Rossiya television.
"The operation continues. We have a day, and intensive, active measures will be taken to rescue the AS-28 vessel and the people aboard," he said.
Dygalo and other officials had said earlier the mini-submarine had enough air to last for five days. The confusion was apparently caused by the fact that seven people were on the vessel, which normally carries a crew of three.
The AS-28 'Priz' minisub can operate at depths of 1,000m, but 190m is
too deep to allow the crew to attempt escape
The vessel, called a bathyscaphe, was in the Berezovaya Bay, about 70 kilometers (43 miles) from Petropavlovsk-Kamchatsky, Russian news agencies reported.
The accident took place almost five years to the day after 118 seamen died in the Kursk nuclear submarine disaster in the icy waters of the Barents Sea.
Some sailors survived for hours following explosions on board but oxygen later ran out. Russian authorities were criticized for their handling of the crisis.
The AS-28 was built in 1989. It is 13.5 meters (44 feet) long and 5.7 meters (18.7 feet) high and can dive to depths below 500 meters (1,640 feet), according to The Associated Press
A vessel of the same type was used in the rescue efforts that followed the Kursk disaster.
Japan said it had sent a vessel carrying submarine rescue gear and three other ships to join salvage efforts, but they are unlikely to arrive at the scene until early next week.
Pentagon Correspondent Barbara Starr and Producer Nastya Anashkina contributed to this story.
August 5, 2005