Cabin Fire

- James Albright (a former G450 driver)

Updated: 2017-06-18

Here are two statistical facts to put all this in perspective:

  • If you don't put a cabin fire out in eight minutes or less, you probably won't.

  • If you are on fire and don't land the airplane safely in fifteen minutes or less, you probably won't.

The basic cabin fire plan of attack is to get the airplane on the ground as soon as possible. In the G450, the good news is all airplane interior fire/smoke/fumes checklists have been consolidated into one, starting on G450 QRH page EC-8. But by the time you run it, it might be too late. You should have a game plan memorized before this happens to you. It happened to me once and we got the airplane down in 12 minutes. Here's my game plan...

 1. Point the airplane to a runway and get there fast

 
 

You need to think these things through and practice in a simulator, but remember your overriding concern is getting the aircraft on the ground in fourteen minutes or sooner, even if you have to break something. With each simulator practice we get better at this, but there is room for improvement:

  • Point the airplane toward the nearest runway that is long enough to get you stopped. Given a choice between more than one, an airport with an ILS would be ideal (more about this below) and one with fire coverage would be a good choice.

  • Fly VMO. If you don't put the fire out in four minutes or less, chances are you won't be able to. So you want the airplane on the ground. Don't worry about speed limitations that won't keep you from flying the airplane, i.e., 250 knots below 10,000'. Don't worry about being too heavy. (You can replace the landing gear struts, but only if you get the thing on the ground before it burns to a crisp.)

  • Declare an emergency and let ATC know what you are doing, let them adjust to your needs. You can ask them for a vector to the nearest runway, about the weather, and approach availability. And then let them know you want a single frequency, preferably the tower's frequency, because there may be a time when changing frequencies will be impossible. If your aircraft has a radio that is available down to the last bit of electrons on the aircraft, use it. (VHF #1 on a G450)

  • Get the ILS tuned and the autopilot in control as soon as possible. (An LPV would be a good second choice.) Even with EVAS there can be a point where programming the FMS and tuning the radios will become difficult if you can't see them. Once the autopilot has the runway in its electronic grasp, you can have it land the airplane even if you don't have an auto land system. If you lose sight of the instruments, let the autopilot do its thing and once you feel runway below you, apply the brakes. (The flare is a luxury you cannot afford.) I've tried this in a G450 and GV simulator and it works.

  • Get to know how late you need to configure to get the gear down and enough flaps to get the airplane stopped. In the G450, for example, you can fly VMO to about seventeen miles, dial in VREF so the throttles come to idle, pull the speed brakes, select 10° flaps at 250 KCAS, select 20° flaps at 220 KCAS, retract the speed brakes, extend the landing gear, and select 39° flaps at 180 KCAS.

  • The sooner you get the ILS tuned, selected, and armed for the approach, the better. If you have EVAS, deploy it, but take advantage of any cockpit visibility to get the instruments set. It is easier to do without the EVAS than with, but virtually impossible to do once you've lost visibility.

  • Get to know where your critical controls and switches are by feel. You should know how to extend the landing gear by touch only. The same, obviously, is true with the flaps. Not so obvious in most Gulfstreams, however, are the ground spoilers. In the G450 the answer is to put your hand on MCDU #3, feel aft for the six switches, and feel for the guarded switch furthest aft and right.

  • If you have a chance, discuss post landing duties with the other pilot and other available crewmembers. Decide which exit is best, where to funnel passengers — upwind on the grass is best — and who will secure the aircraft. Let tower know where you plan on sending passengers so fire rescue doesn't run anyone over.

  • Put the airplane on the ground. Most aircraft can survive a no flare landing and that may be best for energy dissipation. Practice this in the simulator.

 

2. "Where is the fire?" or "Where is the smoke coming from?"

You are likely to get a panicked "Back there!" so be ready to follow through with:

  • "Is it the galley?"

  • "Is it the baggage compartment?

  • "Is it a laptop or other passenger personal electronics?"

  • "Is it coming from the air conditioning system?" (Most of these vents are from the bottom of the cabin.)

  • "Is it coming from an electrical compartment?"

 3. Decide

You could have something as benign as a packet of hot towlettes that spent too much time in the microwave or you might have a smoldering laptop that will ignite and will not be put out. You may be at 50°N 30°W and not have any options but to stay at altitude. Or you may be overflying the longest runways in the country with the best fire rescue teams known in aviation. In any case, you need to make a decision. If you decide you have a fire or fumes that can asphyxiate all on board, you need to act...

 

4. Act

If you have the option of landing immediately, take it. The PF should execute the emergency descent procedure while the PM does what can be done to fight the fire.

If you don't know where the fire is coming from you need to assume the worst and get rid of all potential sources. This procedure will do that:

  • Get pilots on oxygen, deploy passenger masks

  • Turn all master switches off -- you should be able to find the MFD Display switching panel even with your eyes shut, from there go downward, skip the guarded TRU switches and shut off the four rows of master switches.

  • Open the cross flow valve (you are getting ready to lose the DC ESS) and ensure the main boost pumps are on.

  • Close the isolation valve and turn off the left engine bleed.

  • Turn the Standby Electrical Power System (HMG) Master ON and count to ten

  • Switch both Bus Ties to ISLN

  • Turn the HMG L ESS DC and R ESS DC switches ON

  • Turn both generators OFF

If you have better intel on where the fire, smoke, or fumes are coming from, you can have the PM attack that problem while the PF gets the airplane on the ground. What follows are some pointers for each of these possible scenarios.

Galley Fire

  • Get the crew and passengers on oxygen, if necessary.

  • Point the airplane to a runway.
    - Eliminate galley electrical power with the Galley and 60Hz master switches.

  • Appoint a crew member or able bodied passenger to fight the fire; armed with a flashlight, halon fire extinguisher, and the Personal Breathing Device.

  • Consider venting the smoke through the baggage compartment (see below).

  • Consider venting the smoke through the TROV (see below).

Baggage Compartment Fire

  • Get the crew and passengers on oxygen, if necessary.

  • Point the airplane to a runway.

  • Appoint a crew member or able bodied passenger to fight the fire; armed with a flashlight, halon fire extinguisher, and the Personal Breathing Device.

  • Consider venting the smoke through the baggage door using the smoke evacuation valve (see below).

  • Consider venting the smoke through the TROV (see below).

Passenger Personal Electronics

  • If a lithium battery experiences a thermal runaway, the resulting fire and smoke can become uncontrollable within an airplane cabin. It must be dealt with quickly.

  • A halon fire extinguisher can be useful to temporarily reduce the flames and smoke to the point the device can be relocated to the galley sink where it can be doused with water and ice. (Water to directly cool the batteries, ice to keep the water cool. But ice on its own does very little in this situation.) That may not be sufficient.

  • Placing the device in the convection oven will help contain the fire but will not help with the smoke.

  • Plan on getting the airplane on the ground as soon as possible.

  • There are commercially available bags that promise to contain most of the fire and smoke, this is the one we have:

 
 

Even if the bag works for you, get the airplane on the ground. Runaway lithium batteries have been known to explode violently and the bag may be good, but you don't want to test that. Get it on the ground and get that piece of ordinance off the airplane.

Air Conditioning

  • Smoke and fumes from the air conditioning system can take on engine-like smells, such as oil, hydraulic fluid, or even fuel. The fumes can become thick and incapacitating. The smoke can also be coming from the air conditioning pack itself.

  • At the first sign of air conditioning fumes one pack should be turned off and the isolation valve closed. If you have had any indications favoring one side or another, such as loss of right system hydraulic fluid, favor that engine. If not, select the left side since it has more hydraulic fluid to lose.

  • If the selected side doesn't help, switch it back on and try the other. If that doesn't work, you will have to switch both off, descend, and vent the smoke (below).

Electrical

  • In the event you know with certainty the smoke is coming from a cabin component, you can turn all cabin masters off and hope for the best.

  • An electrical fire can get out of hand quickly and should be handled as given above under "Act."

When in doubt, leave the circuit breakers alone.

See: Air Canada 797

Venting Smoke Using the Baggage Compartment Smoke Evacuation Valve

 
 

  • Ensure cabin pressure controller in FLIGHT mode

  • Place flight observer audio controller panel to H'MIC

  • Person using the valve can plug a headset into Smoke Evacuation Valve panel

  • Open internal baggage door slightly

  • Rotate Smoke Evacuation Valve to VENT SMOKE

  • Once smoke vented, enter baggage compartment to fight fire

  • Once finished, rotate Smoke Evacuation Valve to NORMAL OPS

The Smoke Evacuation Valve has two positions with no in between setting: it either deflates the baggage door seal or it doesn't. In the VENT SMOKE position, the baggage door seal is deflated. The internal baggage door becomes your TROV, the entire length of it. So when the procedure says to open the door slightly, it means so slightly you can just get a sheet of paper through it. Any more than that and you will depressurize the airplane. Once you turn the valve you should see the smoke rush aft to the door. You can modulate this by varying the opening of the door, but not too much!

Another thought is to depressurize the baggage seal and not open the interior door. In theory this would depressurize the baggage compartment and starve the fire of oxygen. I suppose this might be worth a try but keep in mind there is some oxygen, even at FL510. It might be enough to feed the fire and you might be better off fighting the fire. I don't know. On this matter I am told the G450 interior baggage door is the same as the G550's and the only reason we don't call it a pressure bulkhead in the G450 is there isn't a regulatory reason to. Here again I've not seen anything in writing, but thought it worth passing along.

To vent smoke through the TROV:

  • Place the FLIGHT / LANDING switch to FLIGHT (the LANDING position will tend to close the TROV)

  • Open all cockpit and cabin gaspers

  • Place the AUTO / SEMI switch to SEMI (giving you direct input to the cabin pressure controller)

  • Cabin Altitude to 7,900 feet (avoiding the 8,000 foot trip point)

  • Cabin Rate to 1,000 FPM