The National Transportation Safety Board is inspecting the tail rotor gearbox of a Maui tour helicopter that made a hard landing March 28 at Kahului Airport.

None of the seven people aboard the Eurocopter AS 350 BA owned by MauiScape Helicopters Inc. was hurt in the incident, which occurred in the same month that two tour helicopters crash-landed on Kaua'i, killing a total of five people.

In the Maui incident, the helicopter entered 'Iao Valley near the end of an hourlong sightseeing flight when the pilot noticed a problem with the aircraft's yaw, or side-to-side movement, according to an NTSB preliminary report released this week. The pilot manipulated the tail rotor control pedals to no effect and declared an emergency before landing at the airport's Runway 2, the report said. The helicopter sustained minor damage.

A Federal Aviation Administration airworthiness inspector found that a mounting tang in the tail rotor gearbox pitch-change bellcrank was fractured, the NTSB report said.