It is not known what caused last month’s crash. Officials with the National Transportation Safety Board said they are looking at a range of potential issues, ranging from weather to mechanical problems. A key question is whether the Island Express pilot attempted to fly into thickening clouds and fog; N.T.S.B. investigators have asked for the public’s help in gathering photographs of weather conditions near the scene of the crash.

Island Express’s general counsel, Teri Elizabeth Neville, declined to comment in detail until after investigators release their findings on the crash. In a telephone interview this week, Ms. Neville said she was not aware of disputes with safety officials and noted that the company’s four crashes happened before the current management took over. She declined to say when that was, but state records and the company’s website suggest it was in 2012 or 2013.

Mr. Lackey, who was the F.A.A.’s point person for Island Express off and on during his 17 years at the agency, said the tensions between him and the company’s management began sometime around 2005, and N.T.S.B. records show that he issued warning letters to the company.

The records also show that the company’s former owner, John Moore, pushed back against Mr. Lackey’s efforts — in particular, his recommendations to tighten safety procedures on refueling, operating rotors when passengers were boarding, and operations at a helipad in San Pedro, Calif., that Mr. Lackey felt were unsafe. The company also protested when Mr. Lackey failed a pilot on a proficiency check.

Discussions over flying in bad weather came up with all helicopter companies, Mr. Lackey said. Though federal regulations allow helicopter flights in relatively low visibility, given their ability to fly very slowly when necessary, Mr. Lackey said he urged charter operators to consider the risks of doing so and advised them in such cases to land the aircraft and wait for the weather to clear.

He was aware that companies had to balance safety with the need to complete the jobs they were hired to do, he said, and those that did not deliver their customers on time might find their clients going to another operator.

Island Express was one of the few companies to go to Mr. Lackey’s managers to challenge his oversight, he said. After a series of clashes, the F.A.A. in 2008 assigned a new principal operations inspector for the company, records show.