Fun one today on AC 567 SFO-YVR.

Before I even went to SFO, I started getting emails telling me the flight was 20 minutes, etc. etc. until the flight was listed as 1:40 late. The reason noted in the first text I got: "... due to airport constraints from an earlier flight." Did some digging and saw that the inbound was effectively an originator from YVR, and that the plane had come in the previous night from KOA.

So, how does a plane that's been sitting on the ground for over 12 hours get delayed? Before everyone says "a safety issue", I have the answer. Or at least, what one of the pilots claimed was the answer.

According to a PA made by the Captain prior to taxi, there was a shortage of "tow crew" in YVR and their plane was the last one to be hauled to the gate that morning / afternoon. Dunno if that referred to the actual tug operators or the aircraft operator actually in the cockpit. Either way, he sounded moderately incredulous about what happened.

As an FYI, ExpertFlyer coded this as a "DELAY 04" code, which seems to be a bit of an omnibus internal code for AC, at least based on my historical tracking. For instance, this code also appeared when they had the notorious mass F1 deplaning in YUL a while back.