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If a fire occurs in flight, the crew will likely try to land on a diversion airport. However landing presupposes seeing the primary instruments, switches and controls.

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In case the fire is not extinguished in time, how would the crew manage smoke in the flight deck to be able to land safely.

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  • $\begingroup$ Is that real equipment in the picture? It looks like props out of a Batman movie. $\endgroup$ – user2357112 supports Monica Dec 30 '16 at 23:40
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    $\begingroup$ @user2357112 Yes, with the flight deck darkened that much by the smoke, they're lucky Captain Bane was in the left seat. He was born in the darkness; molded by it. $\endgroup$ – reirab Dec 30 '16 at 23:56
  • $\begingroup$ @drewbenn: Apparently it exists only on some aircraft: "a legacy from the B747-100, that opens a small vent in the roof", for UPS, it was not planned to be used: "They deviate from the smoke SOP by pulling the smoke handle [...] Unfortunately , this only compounded the problem as they had effectively put themselves in chimney" $\endgroup$ – mins Dec 31 '16 at 9:13
  • $\begingroup$ I don't understand the question. Are you asking what to do after the fire checklist? Are you a pilot or just doing research? $\endgroup$ – user6035379 Dec 31 '16 at 11:20
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    $\begingroup$ I'm imagining you in an emergency first asking a question on Aviation.SE before decide what to do. $\endgroup$ – noɥʇʎԀʎzɐɹƆ Dec 31 '16 at 20:27
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Smoke is a real challenge on an aircraft. The first course of action, other than extinguishing the source of the smoke, if possible, is to evacuate the smoke. In some aircraft windows can be opened. Some have a system to vent the smoke outside. In the crash of SAA flight 295 it was mentioned that the smoke evacuation procedure on the 747 Combi was to open the entry door in flight.

When UPS Flight 6 had an onboard fire the smoke evacuation system was inadequate and the pilots were unable to land safely. They were unable to see any of the instruments or the runway. It ended in disaster. Many lessons were learned from it and advances were made to help deal with smoke in the cockpit.

There are three distinct problems with smoke:

  • Smoke inhalation Having an adequate supply of breathable air or oxygen is key. On UPS 6 the captain's oxygen supply ran out. He attempted to get to another mask, but succumbed to smoke inhalation before he could get there. There can still be plenty of oxygen in smoke-filled air, but smoke contains many toxins that quickly damage the lungs making it impossible to get the oxygen into the blood. Some toxins damage the hemoglobin in the blood so that it can't pass oxygen to tissues. Some types of material can even produce cyanide when burning.

  • Eye irritation. I was in a house fire once and I can tell you that my biggest problem was the eye irritants in the smoke. Even a moderate amount of smoke contains enough irritants to be debilitating. The smoke in my house was nowhere near being thick enough to prevent seeing through it but my eyes teared up and there was an almost irresistible reflex for them to close. It's very painful and it takes a lot of effort to keep them even partly open. Finding the fire extinguisher was a difficult task. One of the lessons learned from the UPS accident was that pilots needed to have protection for their eyes also. The best solution is to have full face oxygen masks similar to what firefighters wear.

  • Opacity Since a cockpit is enclosed, if smoke builds up faster than it can be evacuated then it can become thick enough to prevent seeing through it. I've read stories of pilots of light aircraft actually sticking their head out the window to land. Seeing instruments is also a problem. One development made in the wake of UPS 6 is the Inflatable Vision Unit. This is a transparent inflatable bag that fills up with clear air and displaces thick smoke to allow pilots to see instruments and out the window.

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    I'm not sure how many aircraft are equipped with such a system, but combined with oxygen and eye protection it could make a big difference in a severe smoke situation. (As was apparently experienced by Santa this Christmas Eve!)

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    $\begingroup$ Inflatable Vision Unit: most pompous name for an overgrown bag of air! (Kudos to whoever thought of it though, that's really clever) $\endgroup$ – Cort Ammon Jan 1 '17 at 3:49
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In the worst case, you can depressurize the cabin and then open a window (at least, on the aircraft with cockpit side windows that can open -- e.g. for emergency egress). This draws the smoke forward and out the open window, likely clearing the air enough that the flying pilot (presumably on the other side of the cockpit!) can see the instruments & the runway.

I've never had a cockpit window open like this in flight, but from all reports it's a bit loud but not unbearable, and not particularly windy inside the cockpit. If the smoke can be controlled through other means, you'll do those first on the checklist, but in case the other steps don't improve matters, this step is available, at least for aircraft with windows that slide open (e.g. the 737) or can be swung inward (e.g. C-130).

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