Researchers conclude that a federal altitude requirement for Hawaii tour helicopters has contributed to fatal crashes in recent years, but their call for eliminating the requirement is less than convincing. Their report neglects to recognize the flexibility of the requirement and the relative unfamiliarity with the islands by the pilots involved in the crashes.

The report by researchers from the Johns Hopkins Bloomberg School of Public Health's Center for Injury Research and Policy suggests that helicopters are prone to accident because “;clouds obscuring mountain peaks and passes are particularly common in the Hawaiian Islands.”; It attributes the risk to a 1994 rule by the Federal Aviation Administration that helicopters maintain altitudes of at least 1,500 feet, which can put them at cloud level.

The researchers looked at tour helicopter crashes in the islands in the 13 years preceding the FAA altitude rule and from 1995 through last year. The number of crashes declined from 37 during the years preceding the rule to 22 in the years following, mostly from aircraft malfunctions and pilot error in both periods.

Only two of the crashes prior to the rule and seven since the rule were caused by “;obscured visibility,”; causing pilots to collide with mountains or other obstacles, according to the report. “;Interestingly,”; it says, “;all nine pilots were extremely experienced,”; and flying through inclement weather “;is an extremely risky undertaking.”;

However, the National Transportation Safety Board found two years ago that pilots of four of the eight weather-related crashes it counted since 1994 were “;relatively new”; to flying in Hawaii, three of them having flown in the islands for less than two months. The NTSB added that the newcomer pilots were inexperienced in assessing the rapid change in island weather conditions.

Actually, the FAA has been working closely with tour operators and allowed deviations from the rule on a case-by-case basis, granting them to more than half of the operators on the basis of their compliance with regulations and their safety record.

Island Helicopters claims to be the first operator to be allowed by the FAA to maintain an altitude of only 500 feet. Making use of it, the company says on its Web site that the deviation “;has tremendously enhanced the quality of the tour and allows passengers to get closer to waterfalls, valleys and canyons in order to appreciate the natural beauty of the islands.”;

An FAA spokesman says pilots for operators lacking the deviation are allowed to fly below 1,500 feet to escape bad weather. Operators would do well to follow the NTSB's recommendations for increased training of pilots, installation of weather technology on helicopters, inflatable floats for those flying above the ocean and improved maintenance.