After a start that came during the Vietnam War, the Marine Corps’ aging CH-53D Sea Stallion helicopters — the type that crashed in Kaneohe Bay in March, killing a crew member — are expected to be completely retired from service in the next year and a half, officials said.

A replacement program could begin as early as September, when the first of 12 newer and more capable CH-53E Super Stallions is expected to take up residence with Marine Heavy Helicopter Squadron 463, a unit now in southern Afghanistan.

A squadron of 12 MV-22 tilt-rotor Osprey aircraft, meanwhile, is tentatively scheduled to arrive in Hawaii in 2014, the Corps said.

The replacement plan comes as the Sea Stallions round out nearly a half-century of use and as investigators continue to look at why one crashed from an altitude of about 300 feet on March 29 just minutes after leaving base on a night- vision-goggle training run.

Cpl. Jonathan Faircloth, 22, an aerial gunner with HMH-363, was killed, and three other crew members were injured.

Faircloth’s father, Dean, said by phone Friday from Pennsylvania that it’s still not apparent what went wrong.

"From the very beginning they said there’s no way to know (right away)," Dean Faircloth said. "I mean, nobody did anything (wrong). Nobody failed at their job."

His son helped maintain the big single-rotor chopper and had attained every maintenance qualification possible, Faircloth said.

"They were at the zenith of ability," said Faircloth, who lives in Mechanicsburg, Pa. "They were all taking care of these planes really well, so it would have had to have been, in my knowledge, something that they wouldn’t have had any way to detect. There were no complaints about lack of parts or anything."

A six-member "aircraft mishap board" continues to investigate the cause of the crash, officials said. A command investigation by Marine Aircraft Group 24, the helicopter squadron’s higher command, also is being conducted.

"There’s nothing we can rule in or out right now," said Lt. Col. David Braman, executive officer for MAG-24.

Injured in the crash were pilot Maj. Clinton J. Collins, copilot Capt. Kevin F. Hayles and crew chief Cpl. Ronnie E. Brandafino.

"They are doing very well. They are recovering very nicely," Braman said. All are out of the hospital except for Brandafino, who has been transferred to a "wounded warrior" regiment in the Washington, D.C., area, he said.

The twin-engined CH-53D first flew in 1964 and became operational in 1966, according to the Navy. In the mid-1990s the Marine Corps consolidated all its remaining Sea Stallions at Kaneohe Bay.

It’s now used as a medium-lift helicopter. Other units fly the CH-53E Super Stallion, a more powerful three-engine variant that fulfills a heavy-lift role.

Most of the approximately 32 remaining Sea Stallions based out of Kaneohe Bay are about 40 years old, base officials said.

Lt. Col. Mark Revor, commanding officer of HMH-363, said when an aircraft has less than five years until retirement, the Corps stops upgrades, and the last major upgrade the crashed helicopter received was improved engines about 1 1⁄2 years ago.

"If you just go off history, it’s a very old aircraft, but it’s performed marvelously for many years," Braman said. "We have received nothing from the (investigation) board, as of yet, and don’t anticipate it right now, (that would) ground them."

AS FAR BACK as 2003, however, maintenance crews were taking several trips a year to a helicopter boneyard outside Tucson, Ariz., to retrieve parts such as engine cowlings that weren’t made anymore.

One of the Hawaii-based choppers crashed on Aug. 13, 2004, on the grounds of Okinawa International University in Japan. The helicopter maintenance crew’s lack of sleep was cited in the investigation as possibly contributing to the failure to reinstall a cotter pin that led to the destruction of the $14.5 million aircraft, the Stars and Stripes newspaper had reported.

Crew members sustained injuries, but there were no civilian injuries in the crash.

In 2006 Sea Stallion squadrons at Kaneohe Bay started to deploy to Iraq, and now regularly deploy to Afghanistan. On April 27, helicopters with HMH-463 participated with tilt-rotor Ospreys in a troop insertion and retrieval near the Helmand River.

Revor said as a cost-saving move, 11 Sea Stallions stay in Afghanistan, and deploying crews fall in on those same helicopters instead of transporting aircraft back and forth from Hawaii.

At least as far back as a year ago, the helicopter that crashed had been in Hawaii, he said.

Dean Faircloth said his son, who was married, liked his job and flying but planned to get out of the Corps and would have been back home about two months from now.

"He was going to come home and go to college for engineering," his father said. "He liked the aeronautic stuff. He probably would have gone into something like that."

Twelve newer CH-53E Super Stallions will arrive between September and next spring, Marine Corps officials said.

The Marine Corps aviation plan has 24 MV-22 Ospreys coming to Hawaii in two squadrons starting in 2014, but officials said the plan could change.

Additionally, 18 AH-1Z Viper attack helicopters and nine UH-1Y Venom transport choppers are expected to be sent to Kaneohe Bay starting in 2013, Marine Corps headquarters said.

"What this is really going to do is provide infantry Marines in Hawaii and the Pacific theater a more full, well-rounded air support package," Braman said.