I'm trying to get the following translated. From looking at the babelfish translation this looks like it might be very interesting. It explains how the TSB investigators ran the air flow tests and had the IFEN hooked up by special permission from the FAA. One thing that stood out was that when they did the test flight they had the screens to the IFEN turned on.

Incidently I did find someone to translate it, will post it as soon as it is done, probably by early tomorrow.
http://www.sonntagszeitung.ch/sz04/S11-6912.HTM

Here is the translation:

Following a test flight: Hot trail in the SR 111 case

Crash experts simulate the spreading of smoke in the MD-11. BY PHILIPPE PFISTER LONG BEACH –

Last Thursday there was once more smoke on board of a Swissair MD-11 – but this time it was allowed by experts to billow out on purpose: During of a test flight lasting around six hours, with activated on-board television cameras, the Canadian SR-111 investigators in California took comprehensive measurements of air flow. They wanted to find out in this way how the fire had spread on board of flight SR111. Apparently the investigators are following a hot trail.

“Yes, we flew an MD-11 to Long Beach, California on January 24,” confirms Swissair spokesman Urs Peter Naef. Before that the SR technicians had to configure the plane especially. The Canadian investigative authority TSB wanted to get a plane that would be practically identical with the “Vaud” that had crashed on September 2, 1998. In particular, the controversial on-board entertainment system IFEN had to be installed here too. Since the US Federal Aeronautics Board (FAA) had prohibited the IFEN, an exceptional authorization was given for the test flight.

The experts apparently believe that they know where the fire started.

After landing in long Beach, the Swissair pilots had to take their leave; on the test flight, only experts of TSB and Boeing were present.

The Canadian team, under the direction of SR-111 Investigation Head Vic Gerden, also installed video cameras, in addition to various measuring instruments, in the cockpit and in the forward area of the cabin. On Thursday the MD-11 took off for its roughly six-hour test flight. High above the clouds the crash experts simulated the spreading of smoke. “For this we used artificial smoke, such as is used in theaters for example,” said TSB spokesman Jim Harris.

Why such an expensive test with artificial smoke and video cameras? “We were thus able to make the air flow in the forward part of the plane visible,” explained Harris. The TSB experts wanted to find out how the devastating fire had spread on board of flight SR111 because they apparently have a theory on what the source of the fire had been.
The measurements of airflow could further support this theory. During the flight the IFEN system was connected to the main power supply and the display screens were switched on. At the same time, different temperature measurements were also made.

The specialists allow hundreds of cables to be scorched through

A cable fire, started by the IFEN, is still assumed to be one of the possible causes of the SR 111 crash. Swissair deactivated the IFEN in all of its planes a few weeks after the crash. For safety reasons, as was claimed at the time. In the meantime it became clear that the on-board TV system which consumed a huge amount of electrical energy would never again be used: In the meantime it was removed from one half of all planes. The manufacturer of the entertainment system, Interactive Flight Technologies has long gone out of business and calls itself now Global Technologies. According to its own statements it has now gone into the Mexican casino business, among other things.

In the meantime, tests with airplane cables continue in Canadian laboratories. TSB specialists allow hundreds of cables to scorch through on purpose – sometimes in clean air, sometimes in soot and smoke filled air. The crumbled insulation material is then subjected to chemical analyses. What the experts want to know above all is this: Is it possible, based on chemical analysis, to isolate those cables that have burned through in clean air? If this is possible, the method can also be applied to the scorched cable sections of the crashed MD-11 - it would thus be possible to prove the origin of the catastrophic fire with a high degree of probability. “The question,” says TSB spokesman Harris, “is to know which cables burned through first and which were first damaged by the fire”. The investigative authority is silent on the results. “We are moving into a new field of science”, says Harris. “The tests are very costly and take much time”.

IFEN costs Swissair 46 million

The certification and installation of the on-board entertainment system IFEN in the MD-11 airplanes of Swissair followed a strange course. Although it is a branch of Interactive Flight Technologies (IFT), an unknown company in the field, it was certified and installed in the record time of six months. IFT promised to install the system free of charge in the Swissair planes. Refinancing was expected to come through the proceeds from video films and games of chance. However the passengers underutilized the entertainment system – IFT encountered financial difficulties and the delivery of the remaining installations was endangered. Because Swissair had previously played up IFEN as the attraction that would bring in passengers, it had to pick up the pieces. The entire on-board entertainment system was purchased for 46 million.

Just wanted to note that this article was written in '00. Looks like the investigators have thought the IFEN was the ignition source all along which was always our impression.