An engine failure during takeoff and departure is one of the few emergencies that forces pilots to take immediate action. Engine failures near the ground offer little time to analyze what has happened, develop a strategy, and put it into effect. For your immediate action to be appropriate, you must anticipate it and think it out.
The options that glider pilots must think about in the event of a tow-rope break might be useful to single-engine pilots who have an engine failure on takeoff. Glider pilots train for rope breaks during aero-tows. In a sense the glider has lost its engine or, at least, the connection to its engine. Glider pilots are trained to know their options and plan accordingly.
Most general aviation aircraft have only one engine, and pilots may not be aware of all of their options in the event of an engine failure during this critical phase of flight. It would seem that the pilots with the least number of engines should have the most comprehensive plan, but that's not often the case. So, if you fly a single-engine airplane and you experience an engine failure on takeoff, let's take a look at what options you really have.
Straight Ahead, Part 1
Pilots who learn to fly in small single-engine airplanes are taught that the appropriate action in the event of an engine failure after takeoff will range from finding an arrival area ahead of the airplane to making an abbreviated traffic pattern and landing on the runway they just departed from. Which option they use depends on their altitude.
If the tow rope breaks while he is over the runway, landing on the runway is the glider pilot's first option. Glider pilots practice simulated rope breaks during training (the instructor pulls the rope release) and they learn to respond quickly. Single-engine pilots train for this scenario as well. They simply lower the nose to the best glide attitude and land straight ahead. The process sounds easy, but many power-plane pilots who do not anticipate the event often spend too much time in the recognition stage. They let the airspeed decay to a point that gives them a high sink rate that can't be arrested before touchdown.
How much runway will you need to be able to land on the remaining runway following an engine failure? Find a good instructor, a long runway, and find out.
Straight Ahead, Part 2
What happens if you're too high to land on the remaining runway, but not high enough to turn back to the runway? The conventional guidance is to simply lower the pitch attitude from the best rate-of-climb attitude (you were climbing at best rate, weren't you?) to the attitude that will produce the best glide speed. Then you pick a good arrival area ahead of the airplane, or an area you can reach with a minimum of maneuvering.
Glider pilots probably have an advantage here because many gliderports are in the country and surrounded by corn fields or similar terrain. However, for airports, "arrival area" may be the operative words because most airports are surrounded by less-than-suitable landing areas. At airports you fly from most often, make a mental note of any usable landing areas off the end of the runways, before you are forced to select one.
To Turn, or Not to Turn
When should you land straight ahead, and when should you turn back to the runway? As with most other phases of aviation, the more planning you do on the ground, the better your in-flight decisions will be.
Here's another trick you can learn from glider pilots. During training, glider pilots learn to call out the altitude at which they can turn around and land on the runway in the event of a rope break. If the student fails to make the call, the instructor often simulates a rope break. It only takes a time or two before the student gets the message. By announcing their turning point altitude, they demonstrate they have planned for a rope break before they leave the ground.
Before you can even begin planning for an engine failure on takeoff, you need two pieces of information. First, the minimum power that will allow your aircraft to maintain level flight at the best glide speed, and second, the altitude, bank, and speed you need to be able to turn around and land downwind on the departure runway. With a little experimentation, you can find out both of these critical pieces of information.
When engines fail, instead of dying completely, they often lose power. To be prepared, and to make an informed decision, you need to know how much power it takes to keep you aloft.
It's easy to find the minimum power that will allow your aircraft to maintain level flight at the best glide speed. Simply climb up to the highest density altitude that you think will occur on the hottest summer day for your part of the country. With the aircraft at or near its maximum gross weight, fly at the best glide speed, and maintain that speed and altitude as you gradually reduce the power in blocks of 50 or 100 rpm. The last power setting you used before the airplane started to descend will enable you to maintain level flight at gross weight.
You could call this your "decision rpm." If you fly an airplane with a constant speed propeller, you will be looking for a manifold pressure with the propeller set at climb rpm. In the event of a partial power failure after takeoff, this information gives you a solid decision-making point from which you can choose to extend the flight, if necessary.
If the engine is producing partial power, did it go below your decision rpm? If so, sustained flight probably will not be an option. If the available power is higher than your decision rpm, then you have other options.
Remember, you have no guarantee how long the engine will continue to run after a partial power failure. Do not make the decision lightly to bypass a possible landing area for a better one if you will need the engine to continue running to reach it.
How Much Bank?
If you have the altitude to turn back to the airport, what bank angle should you use in the turn, and what speed should you maintain in that turn? Again, it's easy to learn this information, and glider pilots have done some of the homework for us power pilots.
In the event of a rope break during an aero tow, a glider pilot will make a 45-degree bank turn back toward the runway. Why 45 degrees of bank? It gives you the best tradeoff between rate of turn to increase in stall speed. In a 45-degree bank turn, the airplane's stall speed will increase by about 20 percent.
An airplane's pilot's operating handbook (POH) may specify the stall speed in a 45-degree bank turn. If it doesn't, you can calculate this speed by adding 20 percent to the airplane's wings-level stall speed. More simply, multiply the wings-level stall speed by 1.2.
Now you need to find a minimum safe maneuvering speed. You can calculate this by adding 20 percent to the 45-degree bank stall speed. Again, the simplest way is to multiply the 45-degree stall speed by 1.2.
If this new speed is lower than the best glide speed specified in the POH, then use the POH best glide speed in the turn. These factors are based on the premise that you've remained fairly proficient in executing 45-degree bank turns, because any increase in the bank angle beyond 45 degrees will rapidly increase the wing's stall speed.
As an example, take a look at one of the training fleet's workhorses, the Cessna 152. The POH says that in a 45-degree bank turn with the most forward center of gravity, the stall speed for a 1984 Cessna 152 is 48 KIAS (knots indicated airspeed). To find the safe turn-back maneuvering speed add 20 percent to 48 KIAS - 48 KIAS x 1.2 = 57.6 KIAS
No one can fly at 57.6 knots, but if you round it up, 60 KIAS just happens to be the 152's POH best glide speed. So, in this case, you'd use 60 knots in the turn and in level flight.
How High?
Knowing the safe bank angle and speed to fly are important, but the critical piece of information is how high do you have to be to turn around and land downwind on the departure runway? In other words, what is your "turning point altitude"?
When you fly this maneuver, bank control is critical. Banks shallower than 45 degrees result in a greater turning radius that will leave you farther offset from the runway. Banks greater than 45 degrees will give you a smaller turning radius but will rapidly raise the aircraft's stall speed.
To establish what your aircraft's turning point altitude is, on a specific heading climb to a safe altitude at the best rate of climb speed. As you pass a predetermined altitude, say 3,000 feet above the ground, reduce the power to idle. Lower the nose to the best glide altitude and start your 45-degree bank turn. Turn 210 degrees, fly straight and level for about 15 seconds, then turn 30 degrees in the opposite direction.
How much altitude did you lose? A lot more than you probably thought you would.
Why turn 210 degrees? Because if you turn 180 degrees, you'll be pointed in the opposite direction, but the turn's radius will leave you offset from the runway. To correct the offset, you'd need to turn about 30 degrees more to intercept the runway centerline. As you approach the runway, use a shallow bank to align the airplane with the runway centerline. Remember that the turn onto final will be at a very low altitude, so avoid steep banks.
Now you have the two pieces of information you can use to make your turn-back decision. First, is the engine at or above your decision rpm, which will allow you to maintain level flight at the best glide speed for as long as the engine continues to run? Are you at or above your "turning point altitude," and can you maintain the bank angle and speed you'll need to turn around and land downwind on the departure runway?
If the engine failure results in power below your decision rpm, you know sustained flight will not be possible - and you must select a suitable landing area. If you're at or above the minimum height necessary to turn around and land (turning point altitude), then you can use that information to decide which is the more suitable landing area - an area ahead of you or the runway behind you.
Now that you're armed with all the necessary data you learned at altitude, it's time to put what you've learned to work where you'll need it the most. Get a good instructor, and try it out. Simulate the engine failure well above your "turning point altitude." From these turns you can find the minimum "turning point altitude" that works best for you. Remember, if the practice turn-back approach isn't working - add power and go around!
Other Considerations
Some other factors may decide whether you can turn around and land. The first is traffic behind you. This will be a problem at a busy airport. If you decide to turn back, you may be going nose to nose with a Boeing 747 that took off behind you. Broadcasting your intentions as soon as possible may help, but not much. One option might be to land on an adjacent runway or taxiway.
Another thing to think about is which way to turn. If you turn into a crosswind, it will reduce the distance you must travel back to the runway because the wind will reduce your ground speed in the turn. If you have drifted off the runway's extended centerline, then turning toward the centerline also will reduce your distance to the runway versus turning in the opposite direction.
Also, don't forget that the headwind you took off into is now a tailwind, and it will increase your ground speed back to the runway. Don't let the rapidly moving ground trick you into believing you're going too fast. The only airspeed that's important is displayed on your airspeed indicator.
Remember, too, that your increased ground speed may translate into a trip off the opposite end of the runway after you land. It is also possible that a headwind on takeoff, combined with the increased aircraft climb performance on a cold day, could put you over the runway but not allow you to land on it in either direction should the engine fail.
The last factor to think about, but the most compelling by far, is the psychological desire to return to the runway at all costs in time of trouble. Many pilots have decided to turn back to a runway based solely on this factor, with varying and often tragic results.
One Good Turn
Single-engine pilots, whether beginners or pros, can take a lesson from glider pilots. Before starting the takeoff roll decide on the appropriate plan of action in the event of an engine failure.
To minimize your exposure in a crisis where you have few options, know the decision power for your airplane and the minimum altitude you need to turn around and land. Also, factor the traffic, wind, and expected aircraft performance into your plan of action for an engine failure. Whether it be land straight ahead, find an arrival area off the airport, or turn back to the airport, you'll feel confident that the decision you'll make will be the best one.
You begin your takeoff roll. You're off the ground. You're climbing out. Your engine begins to vibrate, backfire, and lose power. You know your decision power, and you have it. You know the correct airspeed to fly, and you fly it. You know the turning point altitude, and you have it. No traffic, Good. Using 45 degrees of bank, you turn to line up with the centerline of the runway. You flare, touch down, roll to a stop, and scramble out of the airplane.
Whew, that was one good turn!
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