The US National Guard is investigating the first loss of an EADS North America UH-72A Lakota helicopter as a search and rescue effort continues at the crash site off the coast of Puerto Rico.

The bodies of three of the six people aboard the UH-72A that was reported missing around 19:30 on 20 December have been found, says the National Guard in San Juan. Two more floating bodies also have been found in the area, but their identity has not been confirmed.

In addition to recording the US Army's first UH-72A loss, the crash blemishes the Puerto Rico-based guard unit's accident-free aviation record since 1978, the National Guard says.

 © US Army

The National Guard's other UH-72As have been grounded as part of standard policy following a crash, it says. The investigation also is considering if heavy rain reported as the aircraft went missing played any role in the crash.

"It was very bad weather at that moment," the service says. "Investigators so far haven't decided if weather was a main factor in the crash. Everybody is trying to blame the weather, although this machine is designed to cope with those factors."

The helicopter was piloted by a pilot with 10 years of experience who flew the UH-72A in May 2009 from the EADS factory in Columbus, Mississippi, to Puerto Rico. The co-pilot had six years of experience flying helicopters.

According to local reports, the UH-72A was carrying Puerto Rican prosecutors from San Juan to a major drug bust on the nearby island of Vieques.

The US Army plans to by more than 300 UH-72As to serve as non-combat service aircraft. The Lakota is adapted from the Eurocopter EC145, but is not required to comply with military airworthiness specifications.

Source: Flight International