In-Flight Engine Failures
There are almost an infinite variety of malfunctions and emergencies that could be encountered in flight. As part of your training your instructor will cover most typical emergencies as required by regulations but the one most often practiced is the engine failure in flight. This is because there are so many malfunctions that could result in this type of emergency. Typically, an engine provides signs of impending failure such as vibrations, power loss or smoke. It is intended that you begin the checklist at the first indication of trouble, not to wait until the engine actually fails. While entire books have been written on this topic we will simply elaborate on critical items and how to maximize your chances of getting on the ground safely.
Airspeed – Best Glide
Losing an engine in flight does not mean you can log glider time, even though you are now a glider pilot. Remember that aircraft were flying long before Orville and Wilbur attached engines. It is important you immediately pitch for best glide speed for maximum glide range and time. Yes, technically there is a separate minimum sink airspeed that will keep you aloft slightly longer, but this is generally not recommended as it is very close to stall speed and your range is significantly reduced. Once established, trim for hands-off flight so you can divide your attention without deviation.
An often-debated topic is whether to pitch and climb until reaching best glide speed or to maintain altitude and allow the airplane to decelerate to best glide. There is data to support both arguments, but I teach maintaining altitude to best glide for a couple of reasons. First, it is a smoother transition and easier to trim. Pitching up to decelerate and then pitch down to maintain speed often leads to porpoising and a less stabilized condition. Second, it is consistent with procedures used in other maneuvers such as the traffic pattern. Abeam the threshold you don’t reduce power and climb to decelerate, you reduce power and maintain altitude until you reach the appropriate speed.
Landing Site - Select
If you haven’t already, select a suitable landing site. Proficient pilots are constantly looking for emergency landing sites, even when the engine is running perfectly. Just like scanning for other aircraft it takes self-discipline and acknowledging that complacency can lead to disastrous consequences.
Consider the following when selecting a landing site: distance, wind, surface and obstacles. Ideally you are located directly above a suitable site but if not, look for areas nearby and if none are available look further away. Care must be taken to choose a site within glide range including maneuvering. Once you select a suitable site, identify a particular spot you intend to touchdown. If you choose a small field 1000’ wide it is critical you can put the airplane precisely on a spot to allow room for deceleration. There are too many surface considerations to include here but generally you want to find something as close to a runway as possible. Roads, fields and beaches are generally good choices but don’t forget to consider buildings, power lines, fences and traffic. Also consider obstacles approaching the landing site. Trees may not appear to be a problem when seen from above but can easily top 200’ penetrating a normal glidepath. This will render at least 500’ of the area beyond unusable assuming you don’t come up short and become a tree ornament.
Specific checklist items vary by airplane but all will have you attempt to rectify the problem and restart the engine. Three things are necessary for the engine to run: fuel, air and ignition. What controls do you have to manipulate those systems? Generally you have a fuel selector, fuel pump, mixture, throttle, ignition switch, etc. I strongly encourage you to memorize these checklist items and create a ‘flow pattern’ so that your response is automatic.
Engines need a specific ratio of fuel to air to run properly. If fuel is the source of engine problems it is because you have too much or too little. It is difficult to flood the engine while running, especially at higher power settings, so the engine is usually being starved of fuel. Enriching the mixture, checking the shutoff valve and turning on a fuel pump help remedy this condition. If the engine it not receiving adequate air the indications will be very similar. Carburetor heat, alternate air and adjusting the throttle may restore proper airflow. Lastly, check the ignition to see if the engine runs better on a single magneto.
If mechanical failure is the culprit there is little you can do except nurse the engine and stave off the eventual complete failure. Even a little bit of power is better than no power. By reducing power you decrease engine demand and lower temperatures which may be enough to keep the engine running and reach the nearest airport. Just be sure to have suitable landing sites enroute should the engine quit entirely.
You are gliding towards a suitable site and unable to restart the engine. If time and altitude allow, make sure you review the checklist to ensure a critical step was not missed. Prepare for the landing by communicating and minimize the chance of a post-landing fire or injury. Advise the nearest ATC facility of your status including nature of emergency, type of airplane, number of people onboard and fuel quantity. If you don’t have a frequency readily available use 121.50 and broadcast in the blind. Squawk 7700 so ATC can pinpoint your position and guide local emergency responders.
After communicating shut off the fuel supply with the fuel selector / shutoff valve, mixture control and ignition switch to minimize the risk of a fire on the ground. The battery master switch should be turned off but if your flaps have an electric motor delay this step until your flaps are appropriately set. Direct your passengers, if any, to secure loose equipment and ensure seatbelts are fastened. Open cockpit doors to prevent being trapped inside should the fuselage buckle and jamb the doors shut.
Below 1,500’ AGL it is more important you focus on maneuvering the airplane to land at your selected site with positive control and accuracy. The key to precision is positioning the airplane downwind abeam your specific landing point at 1,000’ AGL. During training you will demonstrate that you can consistently glide to the runway following an engine failure on the downwind leg. Landing in a field is no different. Circle directly above your landing site if possible, or maneuver the airplane so that you enter a standard traffic pattern. You will be much more successful since the performance is predicable from downwind to the touchdown point.
Hopefully you will never be put to the ultimate test but training will significantly increase the chance of a successful outcome. It is highly advisable that you occasionally enlist the help of an instructor to review these procedures. Practice gliding maneuvers on your own to increase proficiency with your airplane’s performance characteristics. If you were told that you would experience an engine failure on your next flight would you be prepared?