Canadian officials are wondering how an Air Canada Airbus A319 crew on a perfectly clear August day appeared to set up to land at a tiny municipal airport in British Columbia, instead of their real destination. The Transportation Safety Board (TSB) is investigating the incident in which the A319, with its gear down and flaps partly extended, lined up for the 75-feet-wide by 3360-feet-long Runway 23 at Vernon Regional Airport. The crew, which descended as low as 780 feet over the city of Vernon, apparently realized its mistake and went looking for Kelowna International, about 30 miles away. The flight from Toronto carried 87 passengers and five crew. TSB spokesman Bill Yearwood told the National Post, "The pilots descended low enough that, for all intents and purposes, they appeared to be lost, and that's a concern." Yearwood is convinced the airliner would never have completed the landing but the incident is being investigated. Yearwood said that because of restricted airspace adjacent to the Kelowna Airport caused by a nearby forest fire, the Air Canada flight had to perform a VFR approach instead of the standard IFR approach. Yearwood said there's some question whether the crew had VFR charts on board. Yearwood wouldn't speculate on whether they might have mistaken Vernon (pop. 35,000) for Kelowna (pop. 100,000) but a Vernon flight instructor said it sure looked that way to him. Tyler Chambers and a student were turning final for the same runway when he spotted the Airbus about two miles to the north of the airport. When the Airbus turned to line up with the Vernon Airport, Chambers said he aborted the landing and veered out of the big jet's path. Air Canada hasn't commented on the details of the incident but an industry insider told the Post the mishap is a "huge embarrassment" to the airline and the crew.