The commander of the Pacific Fleet, Adm. Scott Swift, will lead a month-long review of the recent physiological episodes experienced by pilots flying in the T-45 and F/A-18 aircraft.

The rash of incidents involving pilots in flight who had trouble breathing prompted the Navy to ground the T-45 trainer aircraft in early April. Dozens of Navy flight instructors had refused to fly the aircraft.

In response, Vice Chief of Naval Operations Adm. Bill Moran issued a short memo to Swift telling him to investigate and respond “within 30-days,” according to a copy of the April 21 memo obtained by Navy Times.

“To better inform future operational, fiscal and personnel decisions, [Swift] is directed to lead a comprehensive review of the facts, circumstances and processes surrounding the recent PE’s involving T-45 and F-18 aircrews to include how these issues have been addressed,” Moran wrote.

“It is expected that at the completion of the review you will be able to validate actions being taken and make recommendations with respect to additional actions, if any, that should be conducted,” Moran instructed Swift, according to the memo.

Moran said that Swift is responsible for putting together the team that will lead the review. That team, Moran wrote, will “have full authority to draw on previous work and subject matter experts from across the Naval Aviation and Navy Medicine Enterprise.”

The memo describes these “physiological episodes” as occurring when “aircrew experience a decrease in performance due to the cabin pressure fluctuations, contamination of breathing air, or other factors in the flight environment.”

“The seriousness in which I view these incidents is reflected in the seniority of those leading this review,” Moran said in an April 24 Navy press release. “They will provide a full and open accounting to our aviation community, their families and the public.”