"Sorry, my plane is boarding so I won't be able to talk," is a sure-fire excuse for getting away from the boss. But the addition of wireless Internet service on domestic flights is about to change everything.

The new service is part of airlines' continuing search for new sources of revenue. Charging a fee for checking extra baggage was bad enough, but forcing frazzled workers to remain in constant contact with the office is an innovation too far.

For about $10 for 3 hours and $12.95 or so for longer flights, some domestic airlines are beginning to offer in-flight wireless Internet service that allows users to check their e-mail, surf the net and tap into the company's computer network at 35,000 feet above Omaha.

Delta (DAL) and American (AMR) are experimenting with Wi-Fi service provided by Aircell, and are almost certain to expand the service if customer response is good. Other airlines are bound to match the service to stay competitive. Foreign carriers, including Lufthansa, have offered a similar service for several years.

The Federal Aviation Administration prohibits the use of cell phones in flight because the devices may interfere with the plane's navigation system. But Wi-Fi connections don't pose that hazard. That's likely to mean constant e-mail queries from your favorite micromanager.

Those who see the BlackBerry as an electronic tether haven't seen anything yet. But the new service could turn the passenger cabin crew into nannies and schoolmarms.

It's easy to imagine a passenger in cattle class tapping into something that offends the passenger in the next seat. The offending material doesn't have to be porn, but it could be Debbie Does Airport Check-In (or worse) easily enough. So what's the cabin crew to do?

For starters, the crew may handle the offending Internet user like a passenger who's had too much to drink and simply cut him off. This is bound to raise cries of "Censorship!" among the litigious.

But the math is compelling for the airlines. If 150 passengers on a domestic flight pay an extra $10 each for wireless Internet service, the airline generates an extra $1,500 in revenue per trip. That's not all gravy, of course, but during the downturn it could help make up for empty seats.

Scriptwriters are bound to cook up a story where terrorists use the new Wi-Fi service to hijack a plane. It might make a good yarn, but thugs would board the plane with mayhem in mind and wouldn't have to send an e-mail to HQ asking, "Mother, may I?" And investigators wouldn't have to be Jack Bauer to track down the recipient on the ground.

Fuel prices spiked last summer, pummeling many airlines into the red. The worldwide recession is a double whammy as more business and leisure travelers stay home. So, let's hope wireless Internet service generates great gobs of money for the struggling airlines.

What the world needs now is a new excuse for dodging the boss. Somehow, a postcard from Tahiti reading, "Damn! I spilled my third martini on the keyboard, shorting it out and sending the **@@@&^%#!! thing to computer heaven" won't quite cut it.