Pelican’s Perch #52:
The C-131 Emergency Checklist

John Deakins last column about the normal-procedures checklist he developed for the CAFs C-131 (Convair 340) produced such an enthusiastic response - and so many good suggestions - that John decided to devote this month's column to the planes emergency checklist. If youve ever wondered about what goes on in a complex radial-engine transport aircraft cockpit when the kimshee hits the fan, wonder no longer.

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Pelican's PerchMy two previous columns about CAF’s “new” C-131 and the development of our normal-procedures checklist for it drew such a phenomenal response, and I got so many excellent suggestions by email, it appears to be in my own best interest to put the emergency stuff up here for comment and critique. Keep those cards and lett … er, well, emails coming folks, they help a lot. I hope some of you enjoy the issues and comments on these grand old machines.

Those columns also smoked a ton of people out of the woodwork! We have gone from wondering how we would crew the aircraft, to having two classes of 20 people each! About 50 new members, including some who didn’t want the ground school, but had other reasons for helping out. Not all attendees are pilots, but that’s good – a fair number of those have already pitched in to help in other areas.

Commemorative Air ForceWith that many people, some may not get an opportunity to fly the aircraft until late in the season, and a few may not fly until next season. But many will drop out, some will decide that airshows from the inside are hard work (and fun), and some won’t get along in a volunteer group, so even the least-qualified pilots will get their turn, with a bit of patience.

For me, this has been a very “intense” experience. I’ve had less than 60 days to learn a very complex, brand-new (to me) airplane, and develop a full training program for it. I hope the next time I’ll have more time. Some of the time pressure has eased a bit, we’ve still not cleared all the paperwork hurdles in the transfer of ownership, and an inspection is due, as well. We’re still hoping to have the airplane “up” for training by March.

Here are the expanded emergency checklists, with a link to the “real thing,” as we’ll use in the cockpit.

Comments welcome!


EXPANDED EMERGENCY CHECKLIST

Convair C-131 N131CW

Convair Serial Number 205
USAF Serial Number 54-2809
CV-340 (with all 440 mods)
“Type 2” in Dash-1 (Flight Manual)

Limitations and Performance from the Convair Manual
Systems from the USAF “Dash One”
Procedures and Checklists herein

No emergency checklist can possibly cover all possible situations. Good judgment and common sense must ALWAYS take precedence. These checklists will safety handle the vast majority of failures, but crewmembers must not hesitate to exercise good judgment.

In training, all failures will be “simulated,” and all responses will also be “simulated,” with no vital engine controls actually moved, except for power changes. The one exception to this is for the actual engine shutdown and restart in-flight. Special briefings will be held for this case, but in general, the instructor will simulate the emergency at altitude, over a runway, in contact with the tower. The crew is expected to actually perform the “Prop Feather,” and “Mixture Cutoff,” then call for the cleanup checklists. The remainder of the items will be simulated.

“Boxed” items are memory items, and the “real” checklist is printed on pink paper. (I like pink, so sue me!)

Engine Fire/Failure In-flight

Prop FEATHER

In almost all cases, the “bad” engine will be obvious. In the rare case where the engine “just quits,” the BMEP gauge is by far the most reliable indicator. Lacking that, the ancient litany of “dead foot, dead engine” will work nicely. Both crewmembers should agree that the failure warrants a shutdown, and should confirm with each other which engine it is. It is far better to take it slowly, than to get it wrong. Let the auto feather system handle the worst case, on takeoff. DO NOT reduce the throttle below about 100 BMEP, as 80 BMEP or less will terminate the auto feather process, leaving you in an even worse situation.

Mixture IDLE CUTOFF

This is to prevent the engine from running at a low RPM in full feather, which often fakes the crew into thinking the prop feathering has malfunctioned. Without cutting the mixture, the engine will run quite well at 200 RPM or so, with the prop fully feathered.

Firewall Shutoff PULL

It is recommended to pull this handle anytime an engine is shut down outside the training process. There is no downside, and it just may prevent further complications. The firewall shutoff is NEVER pulled in training.

Author’s Note: There is some discussion over whether to make the cowl flaps a memory item on the engine failure litany. I remember a fairly scholarly article years ago that made a pretty good case that the position of the cowl flaps really doesn’t make that much difference, and indeed, some manuals for the old C-46 suggest that if closed when the fire occurs, they should be opened to the one-quarter position for “maximum effectiveness of the fire suppression material.” Personally, I would prefer not to conduct my own research in this area!

If fire:

First Bottle DISCHARGE

Some manuals call for extensive procedures here. Our procedure is to get the engine shut down so the fluid will stop pumping, and get some fire suppressant going. Once the first bottle is discharging into the nacelle, run the “cleanup” items from the checklist (always instantly available in the cockpit), take care of the “nice items,” and then re-evaluate the fire for the second discharge.

(Consider Emergency Descent)

For ANY fire in-flight, the first thought must be to GET DOWN. Major fires in these old airplanes can cause structural failures in less than 60 seconds (there is film to prove it), and it will take not less than three minutes to get this airplane down to sea level from 9,000 feet or so. If the fire is brought under control, it’s easy enough to stop the descent, and then evaluate the options.

With a serious fire on board, DO NOT attempt to “stretch” the flight to some airport that is even a short distance away. Put the airplane down in the water, or anywhere, under control.

Even without fire, water is by far the best bet for an emergency landing. With a fire, you’re carrying a major fire to the scene, where fuel tanks are very likely to burst. A water landing can only help.

(Time permitting, begin Cleanup checklist)

After the first fire bottle has been discharged, it will take some time to exhaust the entire contents, and the fire will, in all probability, go out once the engine stops. Use this time to proceed with the “cleanup” checklist, so that the configuration will be optimum for the second bottle, if needed.

If fire continues after 30 seconds:

Second Bottle DISCHARGE

Cleanup

This is the “cleanup” checklist for an engine failure, engine fire, or precautionary shutdown.

Power (Good Engine) AS REQUIRED
In general, it’s a good idea for the PF to call for the “next higher” power setting as a precaution. This is very important on a check ride, as it’s a PTS item, along with holding a heading within 5, and altitude within 100′. Outside a check ride, power is less critical, unless there is a compelling need to maintain altitude. That would be unusual, as you will want to proceed to the nearest suitable airport, and land.

Gear AS REQUIRED
Flaps AS REQUIRED
These are “as required,” because you should NEVER need to change them for any engine failure. If you are not preparing to land, the gear and flaps will be up. If you are, they may well be down, and should be left there. But these items are “required” on check rides.

Mixtures AS REQUIRED
The mixture lever of the dead engine will invariably be in ICO (“Idle Cut Off”). The mixture position for the “good” engine is a discretionary call by the PIC. In the usual case, the airplane will be in a shallow descent for the nearest practicable airport, and the mixture and power may be left in a cruise or descent power setting, including a fully leaned mixture until it would normally be pushed forward for the approach and landing.

Fuel Valve OFF
This is a very useful item, for it shuts off the fuel immediately after it leaves the tank. If the engine failure happened to be catastrophic, or some other failure caused damage in the wheel well, this switch will shut off all fuel in the length of the wheel well.

Boost Pump OFF
The boost pump for the dead engine should be turned off, the one for the “live” engine is a judgment call.

Cowl Flaps & Oil Coolers CLOSED
The cowl flaps for the dead engine should be closed, both for minimum drag, and for best fire protection. It probably doesn’t make much difference for fire extinguishing, but it’s worthwhile for the second discharge.

Feather Button LIGHT OFF
If this light is still on when things come to a halt, it indicates the feather pump is still running. The PNF should carefully pop it from the depressed condition, being very careful not to pull it out, which would cause an unfeather, complicating things.

Author’s Note: Readers should not mistake this feathering system for that on modern light twins, which use one lever to both control the RPM, and for feather, by pulling that lever to the full aft detent. There is one system for control of these big props, and another separate system for feather, unfeather, reverse, and unreverse.

Emergency Heat Valve (if needed) ON
The “ON” position CLOSES the heat valve, preventing fire, smoke and fumes from going beyond the valves and into the wing and fuselage. See USAF manual, Page 4-13.

Author’s Note: This one strikes my funny bone. The sole function of this switch is to power or unpower what is effectively an isolation valve that prevents heated air from the augmentors from leaving the nacelle. It is “Normally OFF,” meaning the valve is powered. When flipped to “ON,” it removes power to the valve, allowing it to spring closed. Got that? “ON” means “power off, valve closed.” I think I would have chosen different words.

Electrical Loads REDUCE
With one engine shut down, half the electrical supply is gone, and it is worthwhile to reduce the load. This is not nearly as critical as when the aircraft was operated by the military, but it’s still a good idea.

In-flight Unfeathering

Fuel Valve OPEN
Obvious.

Airspeed 130 OR LESS
It is important to reduce speed to provide for a failure of the prop governor. At and below 130 knots, the prop cannot possibly overspeed with the throttle closed.

Author’s Note: The real purpose of this procedure is for the rare case where an engine might have been shut down as a precaution (running low on oil was not unknown), then the airplane might be flown for hours on one engine (overwater, perhaps) in very cold air, causing the oil within the prop governor to congeal to the consistency of taffy. Not a pretty picture.

Throttle CLOSED
This prevents overspeed as the engine starts, and backfiring from “too much air.”

Prop LOW LIGHT
The governor for the feathered prop must be toggled all the way back to the lowest RPM, and the “Low Light” must be checked. This will set a desired RPM of 1200 after the prop comes out of feather, and any rise above this indicates a governor failure.

Firewall Shutoff IN/ON

If Shutdown more than 5 minutes:

This next procedure is to provide protection from a “hydraulic lock,” caused by oil entering the lower cylinder combustion chambers while shut down. This has been known to happen in 15 minutes, although that is very rare.

Mixture OFF
Starter 6 or 12 BLADES
Any hydraulic lock will be detected within about 1/3 of a turn, so six blades is plenty.

Mags & Mixture ON & AUTO RICH
This is in preparation for the start.

Feather Button PULL & RELEASE
Do not wait for a certain RPM, as soon as the prop starts turning, let go of the button.

Engine Instruments CHECKED
Oil and fuel pressure should rise with RPM.

Generators ON, CHECKED
These shouldn’t have been turned off, but the anal among us seem to find it terribly difficult to leave a switch on for an inoperative engine.

Warm-up 15″/1200 RPM TO 40 OIL 20″/1500 RPM TO 100 CHT

Emergency Heat Valve OFF
This will allow resetting of this valve, see next item.

Starter Arm Switch START 15 SEC, THEN NORM
This will mysteriously reset the emergency heat valve.

Fuel Pressure Drop (Engine runs normally)

This seemingly innocuous indication is actually a serious emergency. It indicates a fuel leak somewhere, and while it can be isolated within the engine or carburetor, it might also be a spray of raw fuel into the accessory section. If at all possible, shut the engine down and land that way. If not, continue at the same power setting until over the landing airport, then shut it down and land on one engine. The theory is that if the engine hasn’t caught on fire at the current power setting, perhaps it won’t. But as the configuration and airflow changes with descent and landing, something may well change inside the engine compartment, and provide the ideal mixture (and spark) to light if off.

Mixture OFF

Some will insist that the firewall shutoff be pulled first, in order to draw any remaining fluids into the engine before shutdown. Not a bad idea, perhaps, but this procedure has been adopted for commonality with the other engine failure cases, to simplify training and check rides.

Prop FEATHER
Firewall Shutoff PULL
Cleanup Checklist (above) PERFORM

Prop Overspeed/Inflight Reverse/RPM Surge or Power Oscillation

This procedure covers many prop failures in flight, and other situations too. Remember, if the IAS is 130 or below, and the throttle is closed, the prop cannot overspeed. At lower speeds still, significant power may be produced with the prop fully flat, using the throttle to control the RPM. Minimum clean airspeed should produce quite a bit of power.

Throttle REDUCE
Airspeed REDUCE

If Power cannot be produced within limits:

Perform Engine Failure Procedure

Smoke Removal

Emergency Descent CONSIDER

See comments under “Engine Fire.”

Oxygen Mask & Interphone ON, CHECK
Cockpit DV Window OPEN

Author’s Note: The term “DV” window will be new to many readers. It means “Direct View,” and some variation of it was on almost all the old airplanes. This was a window that could be opened at the back end of the windshield, but forward of the usual window. This was supposedly located so that the airflow would go around the opening, keeping snow, ice and rain from hitting the hapless airman who needed to see ahead. This always called for tilting the head outboard. My own experience with these leads me to believe that from the left seat, my left eye might get a tiny sliver of “direct view” straight ahead, but my left ear is gonna get awfully wet and cold.

Overwing Exit REMOVE

Author’s Note: The low pressure area over the wing can be vividly demonstrated by removal of the “waist hatches” on some of these aircraft. On the C-46, we usually fly with them removed for better cabin cooling, and there is normally a very powerful suction anywhere near them. Do a full stall, and just before the break, the bubble of low pressure will rise to the level of the hatch, and cause a real ear-popping drop in pressure throughout the airplane. We won’t do this in the Convair, as it is heated and cooled normally.

Electrical Fire/Failure

Emergency Descent CONSIDER
Oxygen Mask & Interphone ON, CHECK

Cabin Compressor DISCONNECT
The theory here is that the compressor (and associated control circuitry) might be the culprit for an unknown source of fire smell.

RPM METO RPM
This is a critical step. We are about to shut down the electrical system, and we may not recover it. Hydraulic governors control the props, but electric “step head” motors, which we will lose, select the RPM. METO RPM will take care of the rest of the flight, if necessary.

(Blowers have been omitted here, as we will not be using high blower.)

Emergency Cutoff Bar PULL DOWN
This turns off the main DC bus, and the generators. But it switches power for the emergency DC bus directly to the battery, leaving a number of items with power, some of which might be the source of the problem. The only critical units on that bus for our VFR/DAY operation is the fire detection and extinguishing system, so unless there is an engine fire at the same time (VERY unlikely), it’s possible you might want to turn the “DC Power Switch” back to “Normal,” at least until the emergency is over. Similar comment for the “1st Officer’s Flight Instruments” switch. The really sharp pilot might just reach up and turn off three switches, the battery and both generators, leaving the entire airplane unpowered.

Electrics

Electrics. (Click for larger photo.)

Instrument Power EMERGENCY
This would certainly be a good idea if in IFR conditions, but if you can do without flight instruments for a time, it might be better to leave this alone.

Author’s Note: Some readers may be thinking, “Boy, that Deakin sure is fussy on this subject of just killing all electrics.” Maybe so. But I’ve had this emergency a few times, and my most recent experience involved an airplane similar to the Convair, where there are just five minor items on the “Hot Battery Bus” (the one that is powered anytime the battery is installed). You guessed it, the smoke and fire came from one of those items. In the Convair, the only item on the “Hot Battery Bus” is the battery relay itself.

Inverters OFF
This item is only preparation for the eventual restoration of electrical power, which is not recommended unless really needed. If a landing can be made without electrics, this checklist can be halted here.

(Land at nearest suitable airport)

If emergency flight must continue:

All switches and circuit breakers OFF
This is also preparation for the gradual restoration of electrical power, and may be skipped if that will not take place.

Battery ON
Generators, one at a time ON
Essential Items Only ON
If at all possible, land without electrical power. In-flight troubleshooting is a chancy matter.

Fuselage Fire

Emergency Descent CONSIDER
Oxygen Mask & Interphone ON, CHECK

Cabin Controller ALT AIR
Starter Arm Switch START

Wing Fire

Emergency Descent CONSIDER
Oxygen Mask & Interphone ON, CHECK

Elec Equip in Wing OFF
Emerg Heat Valve ON
In this case, “On” means “Off.” Go figure. The actual meaning is “ON” means “Disconnect circuitry is activated.” I’ll bet there were meetings on this one!

If Fire in Right Wing:

Cabin Compressor DISCONNECT

Drift-Down

See Manual Page 3-16, Figure 3-5

Emergency Descent (High Speed)

Throttles CLOSED

This procedure should only be used in case of dire emergency. It will probably destroy both engines. It is most effective if the airplane is at altitude, as the surface can be reached much more quickly, but the airplane will have to be slowed down, and reconfigured for the crash-landing/ditching. Push the nose down hard to increase the speed to redline, and fully close the throttles.

Props HIGH LIGHTS

This often-overlooked item is the major reason the high-speed descent is so useful. The props in full high RPM create ENORMOUS drag, and this will increase the ANGLE of descent greatly, meaning there is less distance to the ground, and a greater rate of getting there.

Airspeed 293 MAX

Airspeed is at the discretion of the crew. Vne should probably not be exceeded.

Author’s Note: You will often read of increasing airspeed to “blow the fire out.” One the other hand, I suspect you’ve also heard of “fanning the flames.” Again, I’m unwilling to conduct research in this area!

Emergency Descent (Low Speed)

This procedure is most useful from low altitude, as the airplane will be ready to land (crash landing or otherwise) when it reaches the surface. The nose should not be pushed down nearly as hard as in the high-speed descent, as the first need is to slow down for gear and flaps.

Throttles CLOSED

This is also very hard on the engines, but probably won’t destroy them, due to the lower airspeeds. It is “progressive,” meaning that first the airspeed is reduced to the gear speed, gear down, then the speed is further reduced to allow flap extension, eventually to landing flaps.

Props HIGH LIGHTS
Airspeed 174
Gear DOWN
Airspeed 140
Flaps FULL (40)
Airspeed MAINTAIN 140

Crash Landing

See Manual Page 3-17

Ditching

See Manual Page 3-21

Hydraulic System Failure Inflight

See Manual Page 3-24

Hydraulic System Failure On Ground

This can be a subtle and dangerous failure, so LS must always be alert for a reduction in braking performance, and the RS must monitor the hydraulic pressure closely in congested ramp areas.

Hydraulic Bypass UP

This closes off all the hydraulic systems, except the hydraulic brakes.

Emerg Hyd Pump ON

This will attempt to pressurize only the brake system, using fluid from the very bottom of the reservoir.

Brakes STOP AIRCRAFT

Under no circumstances should the aircraft be taxied using the emergency hydraulic pump, or the air brakes. These are for stopping only.

If aircraft cannot be stopped:

Emerg Air Brakes AS REQD
Engines SHUT DOWN
Gear Pins INSTALL

Electrical System Failure

See Manual Page 3-29

Brake Fire

Wind Direction CONSIDER

For all fires on the ground, the primary consideration is to place the aircraft so that the wind (if any) will blow the fire away from the fuselage. Another important consideration is to place the aircraft so that fire-fighting equipment can get to the fire.

Author’s Note: The conventional wisdom from days gone by is to face into the wind. More recent experience has proven this is not the best way to do it. A fire is more than capable of melting and “blowtorching” its way into the cabin in seconds, as proven by a 737 in England a few years ago.

A digression, if I may? Years ago, while taxiing in after landing at JFK, my very young and inexperienced Japanese First Officer noticed the signs on one of the bridges where the taxiway passes over the access roads. The sign says, “Do Not Stop On Bridge.” After we parked, he asked why. I told him that the bridges were built long before 833,000-pound 747s were even a dream, and that calculations had shown that while the bridges were capable of holding a 747 while rolling, they would probably collapse if the airplane stopped for awhile.

He was silent all the way to the hotel, obviously thinking about this. As we were getting out of the crew bus, he happened to glance at me, and he must have seen the twinkle in my eye, because he burst out laughing, and said, “You were joking!”

Author’s Note: (Added after original publication.) The real reason, of course, is that if you stop on the bridge, you block movement of the emergency vehicles. The wings and engines hang well out over the edge.

Nose wheel TURN TOWARDS FIRE

This will set up a geometry that will hold the aircraft firmly in position using only one brake. A brake fire will probably be fed by hydraulic fluid, so it is best not to use the brake on the side with the fire.

Aircraft STOP WITH OTHER BRAKE
Engine RUN UP ENGINE OVER FIRE

The idea here is to blow the fire down and away from the wheel well and structure until the fire equipment arrives, or until the fire goes out.

Airport Equipment CALL

If fire cannot be controlled:

Aircraft SHUT DOWN AND EVACUATE

Increase in Oil Quantity

Engine PERFORM INFLIGHT SHUTDOWN
This can only be caused by an internal FUEL leak into the OIL system. This will dilute the oil, make it thinner, and burn out the engine bearings.

Engine Fire During START

Engine CONTINUE CRANKING

All radial engines are prone to a “stack fire,” caused by excess fuel passing through the combustion chambers without being lit off, pooling in the exhaust manifold, then being lit off by hot exhaust gas when one or more cylinders do begin firing. These can be spectacular, but are generally harmless in most airplanes. That is NOT true of this airplane, as the outlet of the exhaust manifold is deep within the nacelle, with the only way out through a very long augmentor tube that can be very oily.

Exhaust into augmentor

Exhaust into augmentor. (Click for larger photo.)

The most likely place for this emergency is during starting, and this checklist assumes that. A fire at any other time should be treated the same as an in-flight fire, skipping the feathering step on the ground. Continue cranking, hoping the engine will start. It is also likely that the fire was caused by “flooding” the engine, so the pilot should probably stop priming and also open the throttle until he is certain the excess fuel has been cleared. The mixture will probably still be off, and should be placed in OFF if not. Starter duty times should be ignored during this very serious emergency.

If fire will not go out:

This assumes the fire has spread outside the exhaust system, and flames are coming out of the cowl flaps, or the front of the engine. At this point, it is probably better to rely on the internal fire extinguishing system. First, all possible sources of fuel are shut down.

Mixture OFF
Firewall Shutoffs BOTH PULL
Fuel Valve CLOSED
Boost Pump OFF
Fire Extinguisher BOTH DISCHARGE

Fire extinguishers take some time to fully discharge, so it is probably more effective to discharge one, wait some period of time until the discharge is complete, then discharge the other.

Fire extinguisher panel

Fire extinguisher panel. (Click for larger photo.)

If fire continues:

Both Mixtures OFF
Battery OFF

Note that pulling the “gang bar” in this case will leave some systems powered from the emergency bus. While not a serious error, it is probably “better” to just turn off all power by turning the battery off, as in a normal shutdown.

Evacuate Aircraft (next checklist)

Emergency Evacuation

Passengers and ATC NOTIFY

PIC should decide which exits are best, and notify all on board by any means possible. Meanwhile, the SIC should notify any available facilities by radio.

Firewall Shutoffs BOTH PULL
Fuel Switches BOTH OFF
Battery OFF

Do NOT use the “gangbar,” as that leaves some systems powered from the Emergency Bus.

Crew EVACUATE

The crew should avoid trampling the passengers on the way out.

(End of Expanded Emergency Checklist)


Get Acrobat ReaderHere’s a link to the actual (non-expanded, non-annotated) C-131 checklists we now use in the airplane in PDF format (You will need Adobe Acrobat Reader to view it.)

Be careful up there!

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