Unexpected arrival

Any arrival made under some degree of duress, on or off an airport, that is made necessary by the inability to continue further flight is generally regarded as a forced landing. Often, it's because a pilot exhausted his fuel, starved the engine by attempting flight with a tank that had none left, or mismanaged the mixture. About a third of the time, maintenance or fuel contamination issues are involved. However, when something goes amiss under the cowling, it doesn't always do so suddenly and without warning. A precautionary landing is made at the pilot's discretion when he or she still has options--to investigate an engine that seems to be running at higher temperatures than usual, for example, or to update weather information if unforecast clouds are developing.

Few precautionary landings result in fatalities, although forced landings sometimes do. But being low on fuel, lost, or facing worsening weather--and choosing wishful thinking over the option of a precautionary landing is when we go from the frying pan into the fire. The reasons why some forego having more time, power, and options to plan an approach and landing (and instead wait until there are no options) range from a desire not to ding the airplane in a rough landing, to simple reluctance to admit that something's wrong, or even "analysis paralysis." But for argument's sake, let's say your engine quits on you, and it's a total surprise.

The Journal of the American Medical Association published an analysis of the relative risks in general aviation crash landings (airplanes only) in 1998. Of particular interest is that this study included only NTSB events that resulted from a loss of engine power (8,411 of them, from 1983 to 1992). The unsurprising conclusion was that things often work out a lot better when lap and shoulder restraints are used. But the study also revealed that pilot fatalities result about 5 percent of the time, and even though the airplane sustained substantial damage in nearly 85 percent of all occurrences, in about two-thirds of the cases there were no reported injuries at all.

The relative risks were about twice that for retractable-gear airplanes, and also for twin-engine aircraft. Of course, the bigger the airplane or the higher the stall speed, the more severe are the potential consequences. Based on 1992 data cited in this paper, the ratio of accident occurrences (caused by a power loss, as defined above) was once per approximately 19,000 departures, which may represent many times more than most of us will get to fly. (However, these are not exactly astronomically unlikely proportions.)

Here are some things you should always consider, first from a risk management standpoint:

• Always be mentally prepared to deal with an engine failure at any time.
• Understand your fuel system, manage your fuel properly, use carburetor heat if you even think you might need it, use the right kind of fuel, and check your sumps.
• Memorize engine-failure checklists. They contain vitally important items such as checking the fuel, mixture, carburetor heat, and ignition.
• Always climb out at best rate of climb airspeed, V_Y (unless you first need V_X to clear obstacles).
• Realize that the rotation speeds for many airplanes are barely above their stall speeds; be ready to lower the nose briskly if the engine quits suddenly at a very low altitude.
• Fight the "turn back" reflex; it is a proven killer. Many accidents in both single- and twin-engine airplanes occur right after takeoff during an attempt to turn back to the airport at an insufficient altitude.
• Fly high: At 3,000 feet above ground level, an airplane with only a seven-to-one glide ratio has 50 square miles of potential landing area available. (At 5,000 feet, it's over 135.)
• Over mountainous areas, fly within reach of roads on which you could land in an emergency.
• Install and always use a shoulder harness. Cinch it up as tight as you can; a hard landing is less likely to make a bad impression on you than if your upper torso strikes the panel.
• An exhaust gas temperature gauge and, especially, an instrument showing individual cylinder head temperatures can provide advance notice of a problem, instead of sudden silence.
• Most pleasure flying is discretionary. If you must fly a single-engine airplane at night, pick a night near a full moon, fly higher, obtain VFR flight following, or file an instrument flight plan.
• In a twin-engine airplane, don't fly over inhospitable areas with elevations greater than your single-engine service ceiling, particularly at night.
• Switch tanks only when well within gliding distance of an airport.
• Being obsessive-compulsive can be a good thing: Have a survival kit, extra flashlights, clothing appropriate to the terrain over which you are flying, and water. Always file a flight plan.
• You've done everything you can to manage the risk. In spite of your best efforts, it's clear that a forced landing is in your immediate future. Consider these points:
• Don't panic. Loss of control and subsequent injury become much more likely when you're in auto-flail mode instead of checklist mode. Remember to fly the airplane!
• Keep passengers calm. Also, empower them, and keep them focused. Have someone arm the ELT, and secure any loose objects. Review emergency evacuation procedures, and enlist help scouting for landing sites. Be sure all restraints are tightened, and passengers know to bend forward and down in the crash position just before touchdown, for those with lap belts only.
• Always know where you are. It also doesn't hurt to push that handy "nearest airport" button on your GPS.
• If time permits, remember to shout a "Mayday" if you're talking to air traffic controllers and squawk 7700 if you're not; get all the assistance you can from ATC.
• " There is controversy over whether or not to trade excess airspeed for altitude in the event of sudden engine failure. With a sudden engine failure at cruise speed, pulling back to best glide speed can buy you some altitude.
• Don't just remember best glide speed; have it engraved in memory. Use your trim!
• Also remember best glide speed is weight dependent; the published value is for an aircraft at max gross weight and the speed decreases as aircraft weight lightens. Consider using your vertical speed indicator to optimize your glide; flying five knots slower at lighter weights might make the difference (see "Instructor Report: Energy Management," p. 65).
• Over rural areas, look for the biggest unobstructed field you can find and remember wind direction. Over populated areas, if a glance all around you shows that things are pretty much the same in all directions (and you are high enough to still have some time), head downwind. You should always be aware of wind direction. If you haven't flown far, the surface wind is likely to be coming from the same general direction it did where you left. Whether the engine goes stone cold dead or just starts wheezing, unless you spot something great in short order, by heading downwind you will cover more ground and be able to choose from more places for the inevitable landing. (If you did fly far, that's another motivation for seeking en route METARs and TAFs.) And remember to allow ample altitude to turn back into the wind (unless terrain or obstacles dictate otherwise) soon after you are abeam your chosen spot--land into the wind.
• Even though you are flying a glider, you should still fly a traffic pattern (but a tight one). You can benefit from retaining "normalcy" in an unexpected situation, but remember that the average airplane has somewhere around a nine-to-one glide ratio. That's about six and a third degrees, over twice as steep as the sight picture you are probably used to. At least half of the patterns pilots fly are too far away from the runway to successfully land there if they suddenly need to. And if you're on short final with excess altitude, a forward slip is what you will need to dissipate it safely.
• There are two schools of thought on doors. If you're coming down in the middle of a wheat field, sure, pop them open to expedite egress, but a closed cabin is actually stronger. (However, added structural rigidity might result in the doors being wedged shut if there's structural deformation. Follow your pilot's operating handbook.)
• If you do have the field made, and you want to buy yourself some time, there's a speed not too far above stall speed called minimum sink speed, at which your vertical descent rate is minimized (but again, you're close to stalling, so beware).
• The lower you get, the better you will see what it's really like down there. But gliding downhill to an uncertain future isn't like a game of golf; as a general rule, you might get to bogey it and change your mind once, but changing your mind a second time is probably ill-advised. A mediocre forced landing area with enough altitude is better than a perfect field that turns out to be just short of your gliding distance.
• Hit the softest, longest, cheapest thing you can, as slowly as possible, in a level attitude but still well under control. A crash landing at 85 knots will be (almost exactly) twice as severe as one at 60 knots.
• Flying the airplane always comes first. Your prospects are far better grinding to an unceremonious halt in a cloud of dust than losing control trying to finesse a landing into the greener pasture next door. There is a trade-off between low airspeed (less kinetic energy to dissipate) and controllability (the penalty being higher speed, and higher potential impact forces). Our cockpits can withstand about nine Gs of forward deceleration. That's stopping within one car length, for normal single-engine touchdown speeds. As long as the sink rate isn't high, deceleration is uniform, and you can spread it out over greater distances than that. Ground contact at a reasonably low airspeed may have less impact (to you) than an automobile collision. You do not want to stall and have a nose-low impact.
• Unless the road is deserted and you can really see that there are no telephone poles, wires, or that the median strip really would make a nice turf runway, you risk loss of control or hitting a panicked driver on the ground. (If you have no other choice, land with the traffic, not against it.)
• In mountainous terrain, consider ridge orientation, and if faced with a hilly arrival, landing on gently up-sloping terrain is preferable.
• Landing gear: Extending it is usually a good idea for shock and additional impact absorption, except for soft or muddy fields. Also, for wing-mounted gear there is the risk of a ruptured tank if significant fuel remains on board.
• If that green square turns out to be bushes, brambles, and trees, use your airplane's "dispensable structures" (that is, everything but the cabin) to absorb the impact. Let the wings whack into those bushes; let the landing gear absorb the impact with those rocks. Do whatever you need to do, to keep the cockpit and cabin structure intact. A corn or wheat field makes for very effective arresting gear. (Obviously, this would not be your first choice in a precautionary landing.)
• A plowed field is about the same anywhere, although soil color can vary. In the West and Southwest it may be soft with irrigation water, and a high-winged airplane could easily wind up on its back. Cultivated fields are usually good. The important thing to remember is that you should land parallel to the furrows.
• If the only landing area is small, plant it down. Don't use up precious open space; you'll decelerate much more efficiently in a slide than in a float.
• Flaps should be used only when you are absolutely sure of reaching the selected landing area (assuming you'll correctly compensate for the resulting steeper glide path).
• If there's time, consider sliding the front seats back a little, to--ahem--save face. Again, tighten your shoulder and lap belts.

Jeff Pardo is an aviation writer in Maryland with a commercial pilot certificate for airplanes, and instrument, helicopter, and glider ratings. He has logged about 1,300 hours since 1989. An Angel Flight mission pilot, Pardo has also flown for the Civil Air Patrol.