In Biggles in the Orient, Squadron Leader Frayle was the station commander at Jangpur, an aerodrome north of Calcutta which was the southern terminal of the India-China air supply route. Biggles met Frayle shortly arriving in India to investigate the mysterious disappearances of aircraft on the Jangpur-Chungking supply route. He found Frayle in a bad shape. His station had lost four aircraft and four pilots in the last four days and was down to three officers from an original 18. Frayle looked like he had not slept for a week and was tired and bitter. He told Biggles he had wanted to fly the route himself but had been forbidden to do so by headquarters. Nonetheless, he intended to disobey orders and take one aircraft up himself the next day.
Biggles tried to encourage Frayle and told him to take a rest. In the meantime, Biggles arranged to fly the day's supply run with Flying Officer Bargent. They made a last minute swop to a plane which had not been detailed for the flight and loaded it themselves with Frayle's help. They then took the aircraft to Chungking and returned unharmed later in the day, much to Frayle's delight.
Later in the book, Frayle helped Biggles lay a trap for a suspected enemy agent, Kong Po, the laundryman at Jangpur.