WHAT BROUGHT DOWN SWISSAIR111
The Transportation Safety Board of Canada launches what will become the largest air disaster investigation in the nation's history. They only know that Swiss Air 111 experienced a cockpit fire, but what caused it remains a mystery. It would be a challenging task for the investigators to gather the remains of SWISSAIR111 from the ocean, the remain lie berried under water about 55meters(185feet). It was in a couple of 1,000,000 pieces, so that was the initial challenge and then after that. Of course, when you have so many pieces. You need to determine which are the relevant ones, and what are these pieces telling you about what happened and why?
The search for the wreckage begins
The TSB embarks on a complex multi stage plan. First, divers are deployed to survey the wreckage. They discover that the plane is smashed into millions of pieces as far weather worsens the risk to divers increases. At this rate, the investigation will take years to complete. Stage 2 with help from the United States Navy Remote operated vehicles begin a more detailed search. The ROVs help investigators surveyed the site. But the question remains how to recover tiny pieces of twisted metal from the bottom of the sea? Out of the wreckage, the first breakthrough emerges. Swiss Air 111 black boxes, recordings of cockpit and computer data tell investigators that everything on the plane was working perfectly until the last few minutes.
The investigating team faces a setback when it is found that the last 6minutes of the flight data was not recorded on any of the flight data recorders. This made it clear that the fire had affected the crucial flight instruments and it was the cause of the black boxes not recording any data. With the failure of the black boxes, investigators are no closer to learning how or where the fire started on Swiss Air 111. Stage 3 barges are deployed to scour the seabed for evidence. One by one, sad remnants of the airplane reached the surface. One of her engines, then the landing gear. These were among the largest pieces of Swiss air 111 to be recovered. The rest are mere fragments dredged up in a painfully slow process. Stage four and nearby military hanger provides a makeshift lab for the growing team of forensic investigators. Among them are representatives from the American NTSB, Boeing, Swiss Air and the Royal Canadian Mounted Police. pieces of Swiss Air 111 arrive by the truckload. They are organized into various categories for analysis. Soon the hanger is stacked to capacity with the biggest jigsaw puzzle in the TSB's history.
How did a seemingly small cockpit fire suddenly turn to catastrophe?
the team sorts through nearly 250 kilometers of wiring retrieved from the wreckage of Swiss air 111. Here, the first real clue evidence of fire caused by electrical arcing. Scorch marks on metal revealed that the source of the fire was in the back of the cockpit, directly behind First Officer Löw. An examination of the aircraft wiring plans leads investigators to a likely suspect. The entertainment system in first class.
The system had some major deficiencies it was getting very hot it draw a lot of power. And thereby raising the cabin temperature considerably because it was always running. The manufacturers did not install a simple off switch, in order to install appropriate cooling. The TSB investigators finally think they have the breakthrough they've been seeking.
When Captain Zimmerman, through the cabin bus switch all power to the cabin, should have been turned off, but the entertainment system remained on overheating.
Swiss air immediately disables the entertainment system on the rest of its fleet. But the TSB concludes that the mystery is not solved. Investigators determined that the problem with the entertainment system alone could not have brought down Swiss air 111. The search for answers must continue.
Stage five the TSB decides to reconstruct the MD 11 from the wreckage. A wireframe mockup they call the jig provides a spine for placing tiny pieces back where they once belonged. The reconstruction reveals that the hidden fire spread from the cockpit back into the first class galleys. Some metal showed heat damage from temperatures as high as 1100 degrees Fahrenheit. As the investigation continues, some argue that the actions of the pilots may have contributed to the disaster. Some experts charge that Zimmerman and Löw's by the book approach may have cost them their lives. Unfortunately, in this case, the way the checklist was written. It didn't identify that now start towards the divert. It started more on let's try to see if we can solve the problem. But the TSB considers the timeline investigators determined that Swiss Air 111 would not have made Halifax airport under any circumstances. There just wasn't enough time.
Whatever caused the fire on Swiss air, it happened at a lethal speed. The mystery lingers. Second year passes, then another ambitious operation begins.
The TSB hires a sophisticated Dutch salvage ship queen of the Netherlands. The vessel is equipped with a gigantic vacuum system, capable of dredging even the tiniest pieces of Swiss air 111 from the ocean floor. A mixture of seawater, silt and aircraft are pumped into the ships central hold. This cargo is then pumped into a specially constructed reservoir onshore nearby. When the gushing water drains away, investigators find another million pieces of the aircraft. And one of them may hold the clue to what caused the catastrophic fire. The tedious sorting once again resumes and goes on for weeks.
Finally, after 15 months, they find what they've been seeking one faulty wire. Next to the wire that started the arc was an insulation blanket made of some highly flammable substance. The insulation blankets which line the MD 11 are common on commercial airlines worldwide. They have passed the industry flammability tests which require materials to self extinguish after a reasonable period of time. The investigation takes an abrupt turn. Instead of seeking the cause of the fire. The TSB now focuses on the flammable materials that fueled it.
Now they have their answer. A wire arced in a closed space behind the cockpit. The arc ignited the insulation, which in turn let other materials, such as foams. And plastics the pilots could not sense how quickly the fire intensified, but 14 minutes after they declared Pan Pan Pan the fire disabled all electronics in the cockpit, the black boxes went dead. Forensic examination also help shed light on the desperate final minutes in the cockpit. Löw was in his seat. Captain Zimmerman was not likely fighting the fire and probably dead before impact.
At 10:30, Löw shut down engine two investigators determined that he likely received a warning that the engine was on fire. Chillingly it proved that low was alive a minute before impact. They could not determine whether the passengers were aware of the fire, at least until the very final moments.
The aircraft hits the water with a force of 350 Gs.
The TSB spends 4 1/2 years and 40 million U.S. dollars. The largest air disaster investigation in Canada history. Their conclusion, is 1 powerful message. Flammable materials do not belong on commercial aircraft.
In the aftermath of the disaster, Swiss Air decides to remove the flammable insulate from its entire fleet. They also make changes to checklist procedure, reducing response time in a cockpit smoke emergency. But plagued with financial problems, the mighty airline shocks the industry when it goes bankrupt in October 2001. Flammable insulation that sets Swiss air ablaze remains in 2/3 of commercial airlines today, but not for very much longer.
The US Federal Aviation Administration had given a deadline of 2005 to remove the material from all commercial aircraft. This major overhaul aims to ensure the Swiss air tragedy will not be repeated.
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