3:59 p.m.: According to ABC News, an FBI spokesman has labelled the threat “non-credible,” meaning that everybody can go back through security and try again. Safe travels, everyone!

A phone call to the Alameda County sheriff’s office alleging either a bomb or a terror suspect was on board American Airlines Flight 24 from San Francisco International Airport to New York’s JFK forced officials to prevent the flight’s takeoff this morning. The plane, scheduled for takeoff at 7:30 a.m., was diverted to a taxiway, emptied of passengers, and searched while passengers were interviewed.

Here’s a Twitter feed from one of the passengers, Campbell McKellar, indicating that passengers sat on the plane for about four hours before it began to be un-boarded. Passenger Jay Sears also narrated the events on Twitter.

According to the KPIX website, arrivals and departures at SFO continued unaffected. According to the same source, 163 passengers and 11 crew members were on the plane.

News reports courtesy KTVU, KPIX, KGO, and NowPublic, KCBS.

[youtube]http://www.youtube.com/watch?v=pl-TWH93qTY[/youtube]

Over on Laughing Squid, Todd Lappin found this amazing video from the cockpit of a Virgin Atlantic flight in a 747 as they fly in and land at SFO. It’s full of all kinds of knob turning and checklist checking, as well as amazing views.

In the current SF Weekly, Matt Smith documents how a mysterious corporate entity called SFO Enterprises, formed by San Francisco International Airport managers to extend their reach beyond SFO itself, ruined a project to upgrade the airport in the capital city of Honduras. According to Smith’s article, the project was so messed up that it led to at least one fatal incident when an airliner ran off the end of a runway, killing five and injuring 65. Smith goes on to detail the project, the tortured relationship between the Honduran government and SFOE, and the economic “chaos” that resulted when the government shut down the airport for large jets after the accident.

A Google search points to many SF Weekly articles on the mysterious SFO Enterprises going back at least to 2001, but this latest one is so damning it’s a wonder Mayor Gavin Newsom doesn’t do something.