A senior Air Transat maintenance supervisor told concerned mechanics to proceed with an engine swap on one of the airline's Airbus A330s, despite missing parts, a senior company executive confirmed Tuesday.

The executive, in an interview arranged on condition that he not be identified, confirmed that the team's lead mechanic initially told his supervisor that he couldn't finish installing the engine because parts were missing. He was told to install the engine using the procedure for a slightly different model. That installation was improperly completed, resulting in chafing of parts and a major rupture of the fuel line on Air Transat Flight 236 to Lisbon on Aug. 24.

The aircraft lost power in both engines because of fuel starvation, forcing the pilots to glide the airliner to a safe landing at a Portuguese military air base in the Azores — the only land in any direction for more than 1,600 kilometres.

The senior Air Transat executive, while acknowledging that mistakes were made in maintenance, flatly rejected allegations published in The Globe and Mail this week that the company ignored the mechanic's concerns after the engine was installed. Rather, he said, the concerns were addressed, but the installation proceeded improperly.

"Everyone was acting in good faith," the senior executive said. He said that the lead mechanic who, according to a union official, had taped a telephone call with supervisors to substantiate a claim that his concerns were ignored, had raised no doubts about the installation after it was completed.