Hawaii Sens. Brian Schatz and Mazie Hirono have introduced new legislation aimed at closing key regulatory loopholes for air tours and skydiving flights, following a spate of recent fatal accidents in the islands.

One of the main goals, they said in a statement Wednesday, is to make the state’s more than $100 million air tour industry safer.

“The tragic number of air tour accidents we’ve seen in Hawaii have made it clear that we need to do more to protect passengers and pilots,” Schatz said in the statement.

The bill, dubbed the “The Air Tour and Skydiving Safety Improvement Act,” would close the loophole that allows many tour companies to operate under Part 91 of Federal Aviation Regulations — the loosest possible set of standards meant for general aviation. Instead, those flights would have to operate under the stricter — and more expensive — Part 135.

Earlier this year, the Federal Aviation Administration told Civil Beat that some 18 tour companies operate under Part 91, provided they follow certain restrictions such as taking off and landing at the same site. Another 30 companies operate under Part 135.

The bill would also compel the FAA to enact the recommendations made by the National Transportation Safety Board for skydiving flights following last year’s crash at Dillingham Airfield in Mokuleia, which killed 11 people.

Rep. Ed Case has been particularly outspoken on the issue — he introduced a similar bill, the Safe and Quiet Skies Act, in the House last year. John Goglia, a former NTSB board member and national air safety expert, has said he doubts such air safety legislation would pass in an election year.