ANCHORAGE, Alaska — Two fatal crashes of Alaska commuter aircraft and five other accidents or incidents have led the National Transportation Safety Board to recommend a comprehensive safety audit of the company that provides most commuter air service within the state.

The NTSB announced Thursday an “urgent safety recommendation” that the Federal Aviation Administration review of the businesses operating under HoTH Inc. to check for regulatory compliance and operational safety.

HoTH is the parent company of Hageland Aviation, Frontier Flying Service and Era Aviation doing business as Ravn Alaska, Ravn Connect and Corvus Airlines. In a statement, Ravn Alaska President and CEO Bob Hajdukovich said safety is the company’s top priority. Alaskan-owned HoTH Inc., he said, understands the responsibility of providing safe and essential air transportation services.

“Hearts ache across our whole family of companies due to the recent tragedies,” he said.

Alaskans are challenged by the weather, environment and lack of basic infrastructure and resources that the rest of the country enjoys, he said.

­— DAN JOLING,

Associated Press

The NTSB also said the FAA in Alaska itself should be reviewed. A second, non-urgent recommendation called for an audit of the agency’s oversight, including its workload, inspector qualifications, turnover, and working relationships with operators owned by HoTH.

Agency spokesman Allen Kenitzer said by email that the FAA began increased surveillance of Hageland Aviation in 2011.

“Even before the NTSB issued its recommendations, the FAA decided to send an audit team from outside Alaska to look at the carrier and the FAA’s oversight. The team, which has been on-site this week, consists of highly experienced inspectors with many years of experience auditing carriers and FAA certificate management team activities.”

The FAA will respond to NTSB recommendations within 90 days, Kenitzer said.

Hageland, now doing business as Ravn Connect, is Alaska’s largest commuter airline and one of the nation’s biggest. It operates 58 airplanes with 1,200 weekly flights. The two fatal crashes involved Hageland aircraft under other names.

On Nov. 29, a flight doing business as Era Alaska crashed a mile southeast of the Saint Mary’s airport, killing the pilot and three passengers. Six passengers were seriously injured. The Cessna 208B Caravan had left Bethel for Mountain Village but diverted because of deteriorating weather.

On April 8, another Hageland Cessna 208B Caravan operating as Ravn Connect crashed 22 miles southeast of Kwethluk, killing two crew members. That flight also started in Bethel.

The company had other close calls.

The NTSB letter noted a near-fatal Era Aviation flight with 15 on board that experienced a left roll and descent consistent with a stall on Sept. 5, 2012, near Soldotna. The crew regained control and landed safely.

A Dec. 3, 2012, Era Alaska flight with eight on board made a forced landing shortly after takeoff from Mekoryuk. The NTSB said the probable cause was loss of engine power because of a fractured compressor blade.

On May 4, 2013, a pilot and three passengers suffered minor injuries when an Era Alaska plane crashed on its second attempt to land at Newtok. The probable cause was the pilot’s decision to fly in bad weather, failure to maintain clearance in flat light and a delayed decision to start a “go-around.”

On Oct. 23, the nose and landing gear of an Era Aviation plane collapsed while landing at Homer. Thirteen passengers and two crew members were not injured.

On Nov. 22, an Era Alaska on-demand charter flight crashed while landing at Badami Airport near Deadhorse. The two-person crew and a passenger were not injured but the airplane was badly damaged.

The NTSB identified areas of concern while investigating Saint Mary’s fatal crash, according to the seven-page recommendation signed by acting NTSB Chairman Christopher Hart. Investigators said the operator had a risk-assessment plan in place, but they concluded that it was improperly implemented. The plan had not been integrated into a general operations manual or placed in the FAA-approved training program.

“Thus, flights were allowed to be released without correctly identifying the risks associated with those particular flights and mitigating those risks,” the NTSB said.

The NTSB also found flaws in the company’s command structure.

“The investigation determined that company employees acting as flight coordinators were not properly trained for the job and that the overall experience of company flight coordinators was limited,” the NTSB said.

Flights were released without proper oversight from company officials with responsibility for controlling operations, the board said.

FAA inspectors observed 11 instances of noncompliance connected to flight operations by Hageland Aviation and opened investigations. Between July 2009 and Nov. 29, however, the noncompliance investigations were closed with no action taken. FAA managers requested more staff to monitor Hageland over the two years leading up to the Saint Mary’s fatal crash but none was assigned.

Era Aviation, now doing business as Corvus Airlines, operates with 12 aircraft. Following the unplanned left roll and descent incident near Soldotna, the NTSB detected problems with FAA inspectors who were not aware of the installation of incorrect cockpit voice recorders or operations problems. The NTSB noted inspectors’ lack of awareness for deficiencies by the company in guidance for recovering from stalls and for dealing with severe icing.

“The NTSB is concerned about the deficiencies noted during recent investigations of HoTH, Inc., operators and also with FAA’s surveillance and oversight programs that failed to detect and correct these numerous and long-standing issues of non-compliance with FAA regulations and policies,” the recommendation said.

The board called for an independent review of the operators controlled by HoTH and of FAA oversight.

“Without immediate assessment and evaluation, additional accidents and loss of life may occur,” the letter said.

Hajdukovich said the NTSB request for comprehensive audits is a step behind its own work.

“We have already completed or are in the process of a completing an independent audit of Hageland Aviation,” He said. “All of the factors that the NTSB mentions in its letter have been actively addressed by not only the Ravn Air Group, but the FAA and external auditors.”

One audit includes an Alaska Airlines audit of Era Aviation for codeshare markets, he said.

“We welcome the opportunity to showcase the ongoing improvements to our risk assessment process and overall System Safety programs,” he said.