Wednesday, February 11, 2009

Smoke in the Cockpit

I got the idea for this post after Julie, a Civil Air Patrol 2nd Lieutenant and Girl With Wings, told her fellow twitterers about investigating a report of smoke with an electrical smell at her current place of employment. Julie, who also wants to be a flight attendant, said that she would raise the alarm if she were to smell such a thing in an airplane. See, she is a safety minded crewmember already!

So I wanted to blog about why smoke in the cockpit is such a big deal. From the King Air to the Citation X, every multi engine airplane I've flown has had oxygen masks and goggles, for use during the unlikely event that smoke is generated during flight (fortunately, in-flight fires are rather rare, in comparison to other causes of airline accidents. Read about some of the more notable ones). The Citation X I fly has an additional safety feature, an EVAS. Since my employer is listed on The EVAS website, I can be assured I'm not giving anything away here.

EVAS stands for Emergency Vision Assurance System and is contained in a box located along the wall next to our pilot seats. For someone taller than me, it is in a position where they might hit their elbow. But it needs to be handy. The reason that one would be interested in spending the extra money on this system is that goggles are fine for keeping the smoke out of your eyes, but your range of vision is now limited to the goggles. If the cockpit is filled with smoke, the goggles will not allow you to see through it to the instruments, much less out of the window, making it very difficult to land under this emergency situation.

Since there seems to be no pictures available, I found a good description of the equipment in an article entitled, "Orders for Emergency Vision Equipment Pouring in After Report of "Smoke in the Cockpit" From Swissair Flight 111"

The device, known as the Emergency Vision Assurance System (EVAS), physically displaces smoke in the cockpit by inflating a clear plastic bubble, and keeps it gently inflated through a pump and filter system. The bubble is tailored to fit the cockpit layout of each specific aircraft. It presses against the instrument panel and the windscreen. Pilots can see vital instruments and out the front of the plane by pressing their goggles against the inflated bubble.
The Swissair 111 accident was the subject of a National Geographic program. A clip on YouTube shows the seriousness of the situation: The entire series, though (5 parts), is on YouTube. The most important lesson for pilots to take away from this type of disaster is to never delay landing if smoke is detected. Hesitation may save lives. Lessons learned, courtesy of the International Aviation Safety Association:
When the primary flight displays failed, the crew had to adjust to small standby instruments, which added to the workload (AW&ST Jan. 7, 2002, p. 43). Gradually overcome with heat and fumes, the pilots lost situational awareness, and the MD-11 crashed into the sea at 10:31 p.m. The report notes that although the crew recognized the necessity for a diversion, they did not believe the threat to the aircraft was sufficient to declare an emergency or initiate an emergency descent profile. The report notes that from the time the peculiar odor was detected, "the time required to complete an approach and landing to Halifax . . . would have exceeded time available before the fire-related conditions in the cockpit would have precluded a safe landing."
The driving principal behind development of the EVAS is this fact: At least 1230 lives have been lost in air crashes where smoke and pilots inability to see their instruments was cited as the primary cause. You can see a video of this device in action: Sorry, there are no pictures of it for me to attach!
If you are not a pilot, what can you take away from this? Well, the Miracle Landing on the Hudson, as it's being called, was fortunate that it happened during the day, in clear conditions. Passengers need to be aware that an emergency egression from an airplane may very well be executed in a dark, smoky cabin, that may even be upside down. Please pay attention to the inflight safety briefing. Julie and her fellow flight attendants will appreciate it!

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