The workhorse of Hawai'i's air tour helicopter fleet — Eurocopter's AS-350 series of helicopters — is being recommended for additional inspections after six "events" since 2002, including a crash on Kaua'i last year that killed four people and left three with serious injuries.

The National Transportation Safety Board has recommended that the Federal Aviation Administration:

• Require operators of AS-350 and its sister EC-130 helicopters to perform a wear check, visual inspection and lubrication of the hydraulic power assembly splines and coupling sleeve splines and repeat the procedures at 100-hour intervals.

• Require manufacturer Eurocopter to identify hydraulic pump drive shafts and coupling splines that do not meet design specifications in its AS-350 and EC-130 helicopters and remove the parts from the supply chain.

"We take the NTSB's recommendations seriously," said FAA spokesman Ian Gregor. "We have 90 days to respond to the NTSB recommendations and we will respond in that time frame."

The AS-350, or AStar, is popular with air tour helicopters and with law enforcement agencies, Gregor said.

In Hawai'i, "90 percent of the state uses AS-350s, maybe more than that," said Preston Myers, the owner of Safari Helicopters, who introduced air conditioned AStars to Kaua'i in 1988. "It started off with me. Everybody was flying Jet Rangers. The AStar took hold. It has forward seating, no obstructions and comfort. It's smooth and quiet and extremely comfortable."

Myers said he was the first in Hawai'i to call the AS-350 "the Cadillac of helicopters. That phrase has been copied somewhat and used by tour companies in the tourist magazines."

A few Hawai'i tour companies still fly versions of the egg-shaped Hughes 500 helicopters, Myers said, "but you can't look out forward from the back seats at all and you have a drive shaft right next to your ear, unlike the AStar where there is no drive shaft inside."

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