I don't think that the delay in display is new. I came to that conclusion a long time ago based on tracking via the web and tracking directly with the AC ops system. Trip.com also speaks of the display as "near real time".

I just checked AC124 which was due to leave YEG at 1700. It actually departed at 1708 [according to the AC web site]. Trip.com at 1709 said that it was scheduled to depart in 16 minutes.

Maybe that is the actual queue time assigned by the ATC for that aircraft to take off. So that time is reserved as the departure time and shown on the flight tracker.

Good! Now that's the way it should be handled. I wonder if it was offered to other pax or just the one's who were smarter/yelled louder? http://www.flyertalk.com/forum/biggrin.gif

I bet she had Ken on the cell while negotiating with the agents what she "deserves"! http://www.flyertalk.com/forum/biggrin.gif

OK, now I know something's up.

Yesterday I put my mom on a flight home, that I observed depart late. I also spoke to her last evening, and she confirmed the plane left several minutes late. (We're using the "door closed" as the departure time, so it's not a matter of door or jetway or pushback of takeoff.) It wasn't particularly late, only a few minutes, nothing to be concerned about. It just came up in the conversation of how the flight went.

But checking AC's Status function on their web page indicates the flight departed 4 minutes early. Now I know this to be untrue.

Another lesson learned from US carriers?

The actual departure time of the aircraft that is recorded in AC's system and therefore used to pay pilots and FA is once the pilots release the brakes. At the same time they will turn on "anti-collision" light on top of the aircraft indicating the aircraft is ready to push back. Next step is to call apron for push back and if it is busy they will make you wait few minutes, sometimes even more if there is an aircraft stuck behind you that is waiting for a gate...When I worked as a gate agent I never waited for push back. Once you see the light on you leave the gate area as that aircraft is considered departed.

But surely it would take more than six minutes after arrival time especially for a 343 to get to that point. Yet their system shows arrival at HKG at 21:05, followed by departure at 21:11.

Someone believes in miracles?

Stranger, I think you posted in the wrong thread ;)

It is a computer error likely caused by an aircraft repositioning on arrival. The messages are registered upon main cabin door opening/closing and park brake release/set.

The scenario that I suspect is:
The airplane arrived and parkbrake set. The main cabin door was opened (arrival message sent) briefly, but the ground crew noticed that the aircraft was too far forward or backward to allow the door to open safely. The door was closed, the park brake removed and this gave a departure message to be sent.