The Federal Aviation Administration yesterday ordered airlines to turn off in-flight entertainment systems like the one that might have been involved in the crash of Swissair Flight 111 last year--and not to install any others.

The FAA stressed that only 15 aircraft have the system worldwide, none of them U.S.-registered planes, and Swissair had voluntarily turned its systems off. The sophisticated system offers multiple channels of entertainment, even allowing passengers to gamble.

The Swissair McDonnell Douglas MD-11 dived into the Atlantic Ocean near Halifax, Nova Scotia, on Sept. 2, 1998, killing 229 people traveling to Geneva from New York. Crew members reported smoke in the cockpit shortly before their radio went dead, and investigators for the Transportation Safety Board of Canada have found evidence of a fire in the ceiling above the cockpit. That area includes controls for the entertainment system.

Investigators found that insulation was burned off three of the four sets of wires running to the entertainment system, and there was evidence of electrical arcing, or sparks.

Canadian investigators have not determined whether the system was the source of the fire or whether the damage was done by a fire that started elsewhere.

But the FAA said its review of the system determined that its electrical power-switching system "is not consistent with the design concept of the MD-11 airplane because it limits the flight crew's ability to respond to a smoke or fumes emergency."

In trouble-shooting a smoke emergency, flight crews go down a checklist that removes electrical power from all nonessential passenger-cabin systems. Although the entertainment system would eventually be turned off as the crew goes down the checklist, "the installation could be confusing and could possibly cause a delay in identifying the source of smoke or fumes," the FAA said.

Investigators found that on the Swissair aircraft the system was wired in such a way that the pilots would not turn it off when they turned off power to other systems in the same area. As the pilots waited to see if the smoke decreased after turning off power--the standard procedure--they would not know that the entertainment system continued to receive power.

The FAA did not address another concern that came up during the Canadian investigation: that the powerful system produces an unusual amount of heat when in operation.

The system draws a lot of power to operate its multiple features on flat color LCD screens at each seat. In addition to gambling, the system offers touch-screen access to a dozen movies and music in 10 languages.