Note the second to last paragraph regarding the IFEN/IFE
The Interactive Flight Technologies Inc. systems provide on-demand video movies and games through passenger-seat sets. Investigators said the supplemental type certificate under which the systems were installed appears to be unique to Swissair, but they were assessing whether installations at other airlines should be examined.
Sixteen minutes before the crash, Flight 111's pilots noted smoke in the cockpit. A string of apparent electrical faults in flight deck systems followed moments later, their sequence captured by the flight data recorder. Teams of investigators focused several weeks ago on the entertainment system as one possible cause.
There was a dearth of physical evidence then, with Flight 111's wreckage under 200 ft. of water on the Atlantic floor. So investigators scoured the MD-11's systems designs and configurations for components and wiring bundles that could account for the reported problems.
The entertainment setup, whose power supply runs through the cockpit, was identified as one system with sufficient electrical energy to disrupt power to the affected flight deck units and with components in a position to feed smoke into the cockpit, but not the cabin. TSB officials said they have no evidence that the smoke infiltrated the passenger cabin.
THEIR ANALYTICAL WORK BEGAN to pay off once investigators were able to examine tons of wreckage retrieved from the ocean floor. Gerden said wiring and wreckage that had been located ``either just forward or just aft of the wall between the cockpit and the cabin'' had heat damage. Investigators now are trying to determine the point in the aircraft from which the heat originated.
NOW EXAMINE THE
FACT 1: IFEN system was connected to an essential bus on sr111 (and 15 other MD11
FACT 2: IFEN is in question as an ignition source on sr111
FACT 3: IFEN could not be successfully deactivated by the crew, given the checklist procedure, since it was connected to an essential bus instead of a cabin bus (which is how it is normally done because an IFE is obviously a non-essential item for flying an a/c.)
FACT 4: Wiring for the IFEN was improperly mixed with the harder Kapton insulated wire in the installation and bent at 90 degree angles against the recommendations of the manufacturer, McDonnell
Douglas. Patrick Price said it's also evident installers used pliers to bend the wires, another
bad faux pas. "You don't dare do that with insulation material -- you might damage it," said
Price (Canadian News)
FACT 5: It was reported in a 1997 Swissair internal newsletter that
Swissair was in a hurry to have this IFEN/IFE installed on their MD11 aircraft. (Source; David Evans, Air Safety Week)
FACT 6: In late October of 1998, Swissair disconnected the entertainment system on their remaining fleet of MD11s (15
sister-ships) because the investigators found the wiring to this system (Tefzel) as well as Kapton wiring in the forward section of the plane to have traces of electrical arcing.
FACT 7: The FAA has issued an AD prohibiting the use of this IFEN/IFE ( unique to
Swissair), to be used on commercial a/c.
FACT 8: The FAA (see Evans/Wojnar interview), stated that the IFEN/IFE was incompatible with the electrical design philosophy of the airplane.*
FACT 9: SBA was both the STC applicant and the approving organization under their
FACT10: Santa Barbara Aerospace who issued the certification for this system, surrendered the DAS on July 1, 1999. The latest status is that SBA has declared
bankruptcy and shut the doors.*
FACT11: Within hours after the crash, before the burnt wiring was discovered by the investigators, the FAA was looking at the
supplemental type certificate (system) installed on the accident aircraft.*
FACT12: The FAA stated (Wojnar) that the installers of this system
"didn't use good industry practices for the installations on the
FACT 13: "The entertainment setup, whose power supply runs through the cockpit, was identified as one system with sufficient electrical energy to disrupt power to the affected flight deck units and with components in a position to feed smoke into the cockpit, but not the cabin. TSB officials said they have no evidence that the smoke infiltrated the passenger cabin." (Source Aviation Week)
FACT 14: QANTAS elected not to purchase the IFE
system from IFT because they determined that the system required too much
power usage.(Source; FACTS)
FACT 15: Although the 'parking' checklist was changed
to reflect the need to shut the MD-11's IFEN system down (on post-flight
shutdown at the ramp) by pulling circuit breakers, the emergency
checklist in fact was not annotated as to it's requirement to be handled
separately (due not being on the CABIN BUS).
FACT 16: Swissair has decided to totally revamp
the MD-11 Electrical System (Jan 00)
FACT 17: In an interview reproduced in Air Safety
Week, The Swissair Chief Pilot admitted that their engineers had to adjust
the control range of the MD-11 air conditioning in order to be able to
counteract the heat output of the IFEN in operation.
*Source: David Evan's (Editor of Air Safety Week) Ronald Wojnar (deputy director, aircraft certification
service, FAA) interview