Case study of Swiss Air flight 111.

1. Case Study: Swiss Air flight 111 crash investigation
Summary: In a flight from JFK to Geneva, pilots began to notice a smell in the cockpit.
Eventually, they found smoke coming from the A/C and decided to detour to Halifax Airport for
an emergency landing. Eventually, flames entered the cockpit and they began to lose functions of
the aircraft, lost communication with ATC and the displays until the aircraft crashed near the
Canadian shore. At daybreak, it was confirmed that all 229 people on board died.
Both of the aircraft's black boxes were found intact 9 days after the crash but it did not provide
any new answers, so investigators turned to the aircraft's remains. The fire was found to be started

2. above the bulkhead in the ceiling of the plane where the pilots were sitting by arching wires that
had sparked and created a fire. Eventually, the investigators found that the wires used for the first-
class entertainment section were the ones to cause a spark, but the metalized mylar insulation
helped fuel the fire.
Problem Statement: The primary problem in this accident was the flammable metalized mylar
that helped spread the fire. The first-class entertainment system wires that were not properly
installed had caused a spark, but there was a chance that if the insulation was made of a different
material, the plane would not have caught fire so easily. This flammable insulation helped fuel the
fire, eventually causing the pilots to lose control of the aircraft and crash. The investigators
assured that the pilots’ decision to detour in order to dump fuel in the ocean did not affect the
crashes outcome.
Critical Factors: The critical factor of this case was the very flammable insulation material
(metalized mylar) the plane had. The arching wires caused the spark but once the fire caught the
insulation, it helped spread the fire. The investigators found several other cases of this material
catching on fire, but the crashes never raised enough attention to ban it. Because the Swiss Air
flight had so many deaths, family members who were affected by the crash began to demand an
answer of why the fire was started, and that is when it was officially decided that the metalized
mylar insulation was the problem.
Alternative Solutions: After this incident, Canada’s Transportation Safety Board made a list of
recommendations in order to prevent further loss of life, many of which have been adopted in the

3. aviation industry. Two of their major recommendations included reforming the procedures for
“smoke from an unknown origin” and banning the use of metalized mylar as insulation.
Reforming the procedures for “smoke from an unknown origin” would change the procedures for
when there is any smoke or odor in the cockpit. Before, the checklist for this procedure did not
cause much of an emergency situation. The pilots were expected to take preventative actions to
keep certain systems from using too much power by shutting off certain functions of the aircraft
like the power in the cabin or the A/C. The recommendation Canada’s transportation board made
is that the pilot should assume any odor or smoke is an uncontrolled fire until proven otherwise.
By adopting this recommendation, any aircraft that faces the same experience will be forced to
land as soon as possible and will possibly prevent another major accident from happening.
A disadvantage of this would be that those airliners would have to retrain their pilots to follow the
new procedure and then incorporate that into their regular training. In my opinion, though, this
disadvantage greatly outweighs the danger posed by not having the change made. Aviation is an
industry that is and should continue to be very “safety first” focused industry. Without safety,
aviation would not be where it has grown to be today.
The second recommendation Canada’s transportation board made was to ban the metalized mylar
insulation. Taken from Canada’s Transportation Safety Board website is a direct quote from
recommendations from the investigators of the accident:
“the Board called for regulatory authorities to take action, on an urgent basis, to reduce or
eliminate the risk associated with the use of MPET-covered insulation blankets in aircraft. The

4. Board also recommended that regulatory authorities test all thermal acoustic insulation materials
against more rigorous test criteria, and that flammability standards for material used in the
manufacture of any aeronautical product be revised, based on realistic ignition scenarios, to
prevent the use of any material in the construction of aircraft that sustains or propagates fire”
(Summary of Occurrence).
Banning the flammable material altogether would greatly increase the safety of the aviation
industry. Many deaths could have been prevented if there had been different insulation installed in
the first place.
The video points out one disadvantage that is worth talking about. It mentions that even though
western countries have mostly stopped the use of metalized mylar in their aircraft, other
developing countries were not persuaded to remove it from their planes. It was not until May 26,
2000 that the Federal Aviation Administration made an Airworthiness Directive to the Federal
Register about banning the material on the effected aircraft, making it officially banned
(Airworthiness Directive).
Another disadvantage of banning the material would create would be the amount of time it takes
for companies to do so. Airliners would lose a lot of money during the time they would have their
aircraft grounded in order for the work to be done on them. They could potentially lose business
and customers as well.
A recommendation made by the video was to remove the unnecessary first-class entertainment
system from all Swiss Air aircraft. The advantage in this would be there would have been no

5. spark to begin with, but there also would be no guarantee it would prevent another fire from
starting. On top of that, the investigators were not 100% sure the wires for the entertainment
system were the ones who sparked in the first place. They made an assumption but it could not
really be confirmed.
Whether or not these solutions could have been resolved without legislative interaction would
depend on the airliner. Swiss Airs (and other companies using this type of aircraft that had the
flammable insulation) would have had to realize the dangers of material and make the necessary
changes. But, since this type of accident happened multiple times before without anyone stepping
up and making the change, I do believe it was necessary to involve legislative interaction.
The disadvantages could have been minimized if the aircraft manufactures had started out with a
different safer insulation in the first place. Even if the airline had noticed these accidents
happening in the first place, they could have slowly decided to change the type of insulation they
used in order to prevent such a problem from happening. This would avoid the problem of having
to ground all aircraft at once in order to change out the insulation.
There would be many costs for any change that happens. The airline would have to employ
maintenance personnel overtime in order to get the changes done quickly. Grounding aircraft until
the changes have been made would also have a huge cost effect on the company. They would lose
customers to high prices or lack of routes available and would most likely have to contract other
airliners to pick up their routes.

6. Recommendation: My recommendation for this incident would be the same as the one Canada’s
Transportation Safety Board; to ban the flammable metalized mylar. By doing this, the aviation
community has become safer than before. The banning of the material has greatly improved the
safety of aviation and I agree with the regulations that were made.
References
“Airworthiness Directive.” Federal Register, Department of Transportation, 26 May
2000, http://lessonslearned.faa.gov/SwissAir111/AD2000-11-02.pdf
“Summary of Occurrence.” Transportation Safety Board of Canada, Government of Canada, 14
Feb. 2013, http://www.tsb.gc.ca/eng/medias-media/fiches-facts/a98h0003/sum_a98h0003 .asp
Tutan, Numra. (2015, August 6). 2015 Air Crash Investigation New Episodes Swiss Air Plane
Crash. Retrieved from https:// www.youtube.com/watch?v=mJGJzm2A6d8