The board's criticisms were part of a review of two fatal crashes on Kaua'i by sightseeing helicopters.

In a Feb. 27 letter, the board suggested that a September 2004 accident that killed five people might have been prevented.

"The Safety Board concludes that the FAA has not provided sufficient resources for the Honolulu (office) to implement air tour surveillance. Such surveillance, in the months before the accident, may have detected and corrected the accident pilot's risky flying practices, such as low-altitude, off-route ridge crossings, and flight into clouds and reduced visibility."

Because the FAA is still not enforcing certain regulations, the safety board feared some pilots may be ignoring rules and endangering passengers, particularly in bad weather.

Calling for greater surveillance and enforcement, the letter said, "The safety board believes that the FAA should develop a permanent mechanism to provide direct surveillance of commercial air tour operations in the state of Hawai'i and to enforce commercial air tour regulations."

In the 2004 accident, a Bali Hai helicopter plowed into a mountain. The second accident occurred a year later when three people were killed after a Heli USA craft flew into a storm and crashed into the Pacific Ocean.

Today's helicopter crash occurred at Princeville Airport at around 3 p.m. The first reports indicate that the pilot of a Heli USA helicopter radioed his company dispatcher saying he was having problems with the hydraulics system, a news release from the Kaua'i Fire Department said.

Air tours are one of Hawai'i's most popular attractions. About one in 10 tourists who visited the Islands in 2005 took an air tour, state tourism officials said. That is more than 750,000 passengers paying about $200 for a typical 45-minute ride.

The safety board said it had been concerned about FAA staffing since 1990, when a report concluded that "at least three accidents" in the Islands may have been prevented if the Honolulu office had enough people and guidance to maintain adequate surveillance. Five years later, the board made more recommendations on staffing.

The FAA responded with plans to adjust its workforce to take into account the board's recommendations. But continued staffing problems "clearly show the FAA has not effectively implemented its plan," the board's letter stated.

At the time of the Bali Hai accident, the FAA office manger in Honolulu estimated that the office was about 10 inspectors short, the NTSB letter said.