What to do after your airplane becomes a glider
Forced landings are one of the most feared scenarios that run through a pilot's mind. It's understandable since, following an engine failure, the pilot loses much control of the vertical dimension of flight. Face it, you're going down and all responsibility lies on you to make the outcome survivable.
Immediate Action Items
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In this article we will assume that you have already determined that the engine cannot be restarted and you've either contacted or attempted to contact air traffic control (ATC) in order to get some help after the inevitable landing (see " In-Flight Emergencies: Engine Out," January Pilot). You've likely had either a catastrophic engine failure or some form of pilot-induced failure such as fuel starvation or exhaustion.
Working on your side is the fact that forced landings are usually very survivable. According to a recent study in the Journal of the American Medical Association, only 5.2 percent of forced landings result in pilot fatality. In 69 percent of the crashes there were no injuries at all. Given these statistics and provided that you are over relatively benign terrain, you and your passengers' chances of walking away unscathed are good. Even at night or in relatively low IFR conditions, if your emergency landing spot is in a harvested wheat field, you'll probably be fine.
Then there are the psychological factors. Unless you've "been there, done that," chances are that a bona fide engine failure will add an element of surprise and anxiety that wasn't present when your instructor simply pulled the throttle back to idle in the traffic pattern. The key to surviving the forced landing is not listed on any checklist — don't panic. Once panic sets in, a pilot is more likely to lose control of the airplane, which exponentially lowers the chances of survival. Think of what needs to be done to survive, not "Why me?" or "What's going to come of my pretty little airplane?"
Know and nail the speed
In your troubleshooting to figure out why the engine quit, don't dally around the cockpit oblivious to your piloting duties. Nail the best-glide speed. It should be on the emergency checklist. Look it up in your pilot's operating handbook and remember it.Should you climb to slow the airplane to best glide-speed? No. If the airplane hasn't already slowed to or beyond the best-glide speed by the time you've realized that you have a real problem, there's not much use in trying to climb a few feet to "buy some more time." If anything, the energy wasted by pulling more than one G to establish a climb negates the supposed gain in glide time. If you don't know the best-glide speed, shoot for a speed at or near the best-rate-of-climb airspeed — they are usually very close.
Once you're established at or near the best-glide speed, you can fine-tune the efficiency of your glide based on indicated rate of descent on the vertical speed indicator. At light weights, the best-glide speed of a Cessna 172 can be a full five knots slower than that published. Once the speed is nailed, trim the airplane to fly hands off to allow yourself time to troubleshoot the problem or find a suitable landing spot.
Where's the nearest airport?
Got a GPS or loran? Put it to work for you. Most lorans and GPS units have a nearest-airport function. These units list the bearing and distance to the airport; many may offer the orientation and length of the longest runway. Scroll through the choices to find the nearest suitable field. Sometimes there are plenty, sometimes there may be none within gliding distance.Keep in mind the winds aloft if you're going to try to glide to an airport. If you were clawing your way into a 25-knot headwind before the engine quit and there are suitable airports five miles ahead and seven miles behind, your best bet is the one behind you. Turn around and your 75-knot glide speed provides a 100-knot groundspeed instead of 50 knots. Of course, you'll need to maneuver back into the wind for the slowest possible touchdown.
Stopping the prop
Stopping the propeller can add some length to your glide since the drag produced by a windmilling prop attached to the weight of a now-dead engine will be eliminated. However, this maneuver should be considered only if you're at an altitude high enough to negate the effects of bringing the airplane to the brink of a stall to get the propeller to stop windmilling. If you're below 5,000 feet agl, we see no value in attempting this maneuver (see "Stopping the Propeller," January 1995 Pilot). Of course, if the engine seized, then the propeller will already be stopped.For airplanes equipped with constant-speed propellers more glide distance can be obtained by simply pulling the prop control to the low-rpm/high-pitch position to minimize drag. Of course, if the engine has lost oil pressure, the propeller control probably won't work. Most propellers revert to the high-rpm/low-pitch setting if oil pressure is lost. This, unfortunately, creates the most drag.
Gear up or down?
For those of you who have a choice, should the gear be up or down? It depends mostly on the terrain upon which you will land. A road, smooth dry field, or other inviting terrain could make a gear-down landing very successful.Forget all the heroic stories of the pilot who "saved the airplane" by making a successful forced landing with the gear down. If it looks doubtful, leave the gear up. Occupants who are strapped in fare quite well when the force of the crash is forward. If the gear is down and the airplane rolls through deep mud and flips on its back, you've lessened your chances of survival and done a lousy job of "saving the airplane."
Check your airplane's POH for gear position. In a situation where a forced landing is made with an excessive sink rate, the landing gear could help to absorb that spine-crushing initial contact. Keep in mind, however, that if a landing gear gets torn off a low-wing airplane it could take a fuel tank with it, increasing the chance of a fire.
Other preparations
Despite the flurry of thoughts running through your head as you glide back down to the surface, you need to consider what will happen during and after the crash. Prepare the occupants. Those with lap belts only should be in the head-down crash position and belted around the hips as tightly as possible. This position is extremely useful for rear-seat occupants in some Cessnas since the extended flaps may penetrate the cabin at head level as the wings shear off. Front seaters should slide their chairs back (making sure that they're locked in place) to provide more distance between them and the instrument panel. Shoulder harnesses, if equipped, should be as tight as they can possibly be.The worst thing that can happen is a fire. Since most GA airplanes lack a fuel dump valve, the only thing you can do is shut off the fuel valve, turn off the pumps, and, in some airplanes, pull the firewall air-control knob that will hopefully prevent any flames in the engine compartment from spreading to the cabin through the heating ducts.
Of course, a fire needs an ignition source, so it's best to start eliminating the possible sources as you near your landing point. Don't turn off the master switch prematurely because your transponder is giving out valuable information to ATC, as is the GPS to you. You may also have electrically operated flaps and landing gear that need to be lowered. Aim to kill the master switch somewhere in the last few hundred feet of the glide. If it's night and you're heading for rough terrain, it's best to leave the landing lights on for any last-second maneuvering that may be required. But the goal is still to turn the master off before impact.
A hot engine could be a source of ignition as well, so anything you can do to cool it down would be advantageous. Open the cowl flaps to bring in more cooling air to the engine. If the distance of the glide is critical or the terrain is friendly enough for a normal landing, this step should be eliminated in the interest of a longer glide.
Most POHs suggest opening the cabin doors prior to impact. This is another preparation move to ensure that occupant egress is expeditious. It is assumed that a crash will warp the airframe to some degree and possibly wedge the door shut. There's also the chance that the airplane could come to rest on the side with the only door. If that's the case, a swift kick to a baggage door or window should get you free. Most canopy-equipped airplanes have a crash ax that makes a great tool for breaking open a canopy that's wedged shut. In fact, it's a good tool for any aircraft.
Rough terrain
For those of us with Murphy on our side, an engine failure may not occur over nice, flat terrain — or any terrain, for that matter. Ditchings will be the subject of another article in the "In-flight Emergency" series later this year. Keep in mind, since most of the country is in the dead of winter now, that frozen bodies of water make great landing spots, provided you're sure that the ice is thick enough to support a few thousand pounds of airplane.The most important reminders here are to hit the ground or obstacle at the slowest possible speed, under control, and allow the airplane and obstacles to absorb the impact. Lower the flaps and leave the gear up, or configure the airplane as the POH suggests. Single-engine trainers benefit from low stall speeds that liken the impact to that of a 35-mph car accident. Add a stiff headwind into the brew and the landing could be even slower. High-performance singles will touch down much faster, but they are generally built stronger than the trainers.
Forced landings into wooded areas are tricky, depending on the thickness of the forest. Your best defense is to continue your controlled glide into the treetops. If the trunks or large limbs are visible, aim the fuselage between them to allow the wings to shear off and absorb the energy. Again, it's preferable to have a forward impact rather than a downward one, as would probably happen if you attempted to stall the airplane just above the treetops, a procedure that has worked but relies more on luck than anything else.
According to the book How to Crash an Airplane and Survive, by Mick Wilson, in mountainous terrain, it may be advantageous to land on gently upsloping terrain. Wilson recommends approaching at maneuvering speed and flaring so as to achieve a nose-up angle that parallels the slope of the terrain. Landing a little fast is better than stalling the airplane at an angle of attack that doesn't parallel the slope, he says. In mountainous or desert terrain it is advantageous to fly near roads, use some sort of flight following, and have an emergency survival kit on board.
No doubt there are many things to consider here, and in the heat of the moment, the typical general aviation pilot will not remember everything.
The most important things are to not panic and to think about what needs to be done to effect a prompt rescue. With these tasks in mind, you won't have much time for panic. In the meantime, rest assured that you control the most likely source of engine failure — getting fuel to the engine. If you can control that, your odds of an off-airport landing are greatly reduced.
For further reading on forced landings, pick up a copy of Mick Wilson's How to Crash an Airplane and Survive (telephone 970/667-3040; www.crashandsurvive.com). Links to all Web sites referenced in this issue can be found on AOPA Online ( www.aopa.org/pilot/links/links9902.shtml).
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