The Sea Dragon is one of the Navy's niche helicopters: There aren't many of them, they're old, and they specialize in mine-hunting. They're all based at Norfolk Naval Station.
They're also the Naval helicopter most prone to crash, according to figures from the Naval Safety Center.
During the past five years, 25 models of Navy helicopters racked up more than 1.2 million flight hours. Of the 10 major helicopter accidents or crashes during that period -- in which someone died or there was at least $1 million in damage -- three involved MH-53 Sea Dragons.
Helicopter Mine Countermeasures Squadrons 14 and 15, better known as HM-14 and HM-15, regularly send detachments of sailors and Sea Dragons all over the world on rotating deployments. Each squadron has between 600 and 700 sailors responsible for 10 to 12 helicopters.
The Sea Dragons, which first entered the Navy's fleet in the 1980s, may be familiar to frequent users of the Hampton Roads Bridge Tunnel -- they sometimes fly low above the water near Willoughby Spit in Norfolk, Va., often towing a sled that carries mine-hunting equipment.
Both squadrons lost aircraft while on deployments in 2012.
* In June 2012, an engine overheated on an HM-14 Sea Dragon deployed to South Korea, sparking an in-flight fire that destroyed the $51 million aircraft.
* Less than three weeks later, a Sea Dragon from HM-15 operating in Oman crashed during a heavy-lift operation while attempting to move a downed Omani military helicopter. Two crew members died, and the aircraft was destroyed.
* In August 2012, a Sea Dragon assigned to HM-15 experienced engine failure as it was taking off at Bahrain International Airport. The $51 million aircraft was destroyed.
The Navy's accident rate for all of its helicopters was 0.82 per 100,000 flight hours between fiscal years 2009 and 2013. The Sea Dragon's rate during the same period was more than 10 times higher: 9.45.
That's almost double the next-highest accident rate -- 5.41 -- for the HH-60H Seahawk, used primarily for combat search and rescue, special operations and anti-submarine warfare.
The only other major accidents in the five-year period ending in September involved newer variants of the Seahawk. The MH-60R had a rate of 0.63, and the rate for the MH-60S was 0.99.