(RNN) - Two crew members have died after a U.S. Navy MH-53E Sea Dragon helicopter crashed during a training mission off the coast of Norfolk, VA. The helicopter was about 18 nautical miles off the coast when it went down.
Two other crew members remain hospitalized. The Coast Guard is searching for a fifth crew member.
The Navy will not release the names of those who died until 24 hours after notifying family.
Two helicopters from the squadron based in Norfolk were involved in the mine countermeasure training operation.
Navy Capt. Todd Flannery stated the distress call was made at about 10:45 a.m., and the craft went down off the coast near Fort Story, which is a naval base.
Capt. John Little, of the Coast Guard, said the cutter Shearwater, a coastal patrol boat, was nearby conducting operations, and no one saw the crash but heard it.
The cutter immediately responded to the distress call and deployed rescue craft. The temperature in the water was reportedly 42 degrees. The helicopter crew members were wearing anti-exposure suits designed to keep water away from the body.
According to the Naval Air Systems Command website, the MH-53E is mainly used to find mines and can operate from carriers. It can carry up to 55 troops or a 16-ton payload, according to the U.S. Navy. They are also used in heavy-lift operations.
The MH-53E is about 99 feet long, weighs about 69,750 pounds, and can travel up to 172 mph. The crew can consist of two pilots and up to six aircrew, according to the Naval Air Systems Command.
According to the Hampton Roads Pilot, the Navy had planned to phase out the Sea Dragons, but did not have replacement ready, so the helicopters were upgraded.
On Tuesday, a U.S. Air Force helicopter crashed on the coast of southern England, killing the four people on board.
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