Other Engine Failures (Instructor)
Excessive in flight idling of the engine will cause the engine to cool to the point that fuel may not vaporize in the carburetor. This drastically leans the mixture and can fail the engine. A sudden throttle movement may make the problem worse. Precautions are to make ground check of idling setting, avoid abrupt throttle movements at all times. Keep the engine warm during glides by frequently opening the throttle for a few seconds.

The essential element of any engine failure is the amount of time you have remaining in the air. You must have a prepared plan to use and a checklist to make sure you follow the plan. The quickest emergency checklist utilizes the cross panel flow. This must be adjusted to each cockpit and aircraft type. The flow of one instrument panel will seldom work on another panel. The flow lets you complete the task flow quickly and even more quickly confirm completion by reference to the checklist.

Weather and its unpredictability is one major area where a pilot's lack of knowledge and proficiency is apt to cause trouble. Typical decisions that cause this difficulty are. "I'll take a look, and then decide type of flight". Trying to climb over or around building clouds. Trying to sneak under or around weather. You may get lucky but just, as likely you will run out of options. The true saying is, "It is better to be down here and wishing you were up there than to be up there wishing you were down here". Never fly into deteriorating weather conditions.

You will never be prepared for an engine failure. An engine failure will never occur at an appropriate time. It takes a minimum of four (4) seconds to become aware that the engine has failed and to wish that it hadn't happened. Don't do anything. 

Get the (# 1) checklist and use it. The pilot who does not have an emergency checklist immediately at hand often becomes just a passenger on the way to the ground.

You must know your aircraft speeds and just to be sure have them on your basic emergency checklist in different colors for the aircraft you fly. There are several engine-out glide speeds. The best glide speed is a lift/drag ratio for best distance. This is between Vx and Vy but will vary by weight. Adding 1/3 of headwind velocity to best glide speed give a penetration glide speed for best distance. The minimum sink speed keeps you in the air the longest.

(# 2) Select a speed and trim for it. Gain any altitude you can with excess speed. 

(# 3) Turn to your choice of field based on wind direction. If at high altitude turn toward lower elevations and make your choice at about 3000' AGL (above ground level). 

(# 4) Go through your engine restart procedure but first undo the last thing you did to engine operation before it failed. Check fuel, ignition and air to the engine. All three are necessary but the fuel system is most likely to fail. Magneto switch is the only ignition element available to the pilot. Throttle and carburetor heat are the air controls for the engine.

Engine restart checklists begin with the fuel selector, to the mixture and gauges. Then right to left the flow goes from carburetor heat to magnetos, to primer. (See below) Practice until you can hit each item with your eyes closed. Then confirm that all items have been completed.

After you have done all the normal things start being creative. (I once had an engine malfunction (failure at 800' over the dense woods of the Arkansas. Pulling the mixture out about two inches caused the engine to begin running again.) Don't expect what you do to make sense but if it works don't ask why until Sunday. Consider that a primer that has worked loose can cause a rough engine. A partially open primer allows raw fuel to get into the engine intake without atomizing as required for proper combustion.

(# 5) Prepare the cockpit and yourself for the inevitable. Tighten, pad, and protect as best you can. Seats belts and doors. 

(# 6) Use your radio 

(# 7) Make your landing crash as slow and as controlled as possible. Fly the airplane. Deceleration impacts increase as the square of the speed. Impact forces at 60 kts are four times those at 30 kts. The cockpit will remain intact to 9-Gs. At 45 kts only 9.4 feet of deceleration will bring you to a stop. Your mission, should you choose to accept it, is to keep you and yours from rattling around inside the cage. (# 8) Prevent fire by shutting off fuel and electricity. When everything stops moving, get out.

The vast majority of engine failures never make Eyewitness News because a successful emergency landing is non-news. Only one out of every seventeen emergency landings results in a fatality. Most pilots will never experience such an emergency in their lifetime.

Dealing with Engine Failure (Instructor)
Dealing with an engine failure depends on a series of factors, pilot competence, type of aircraft, extent of failure, type of failure, altitude, and general weather/surface conditions. Focus must be on keeping the aircraft aloft and under control. The more altitude the more options you have in acquiring assistance. Emergency checklist is the essential safety aid to be consulted as to what to do.

Apply carburetor heat, open alternate air, switch tanks, turn on fuel pump, check primer pump, select magneto, even moderate vibration calls for immediate shutdown.

The standard emergency for engine failure on takeoff is to land ahead into the wind. Make no more than 30 degrees of heading change to locate the best landing place. An emergency landing into a 10 kt wind at a full flap stall speed of 35 kts gives you a survivable ground contact speed of 25 kts. However, there is another option possible if sufficient altitude has been gained before failure. (A good reason to always takeoff and climb at best rate, Vy) To determine this altitude it is necessary to practice at altitude. At 3000' on a North heading, simulate engine failure and have the student execute a right turn in a 30-degree bank to 240 degrees. Note the altitude loss. Do the same 240-degree turn to the left. Note the altitude loss. Now do both turns with 45 to 60 degree banks. Note altitude lost. Add 50% to the altitudes as a fudge factor for actual use.

From these turns you should decide that the steep turn loses the least altitude. Having determined this we now can add some factors for returning to a runway. If there is any crosswind always make the turn into the wind since it will bring you back to the runway. If there are parallel runways turn to the parallel since only 180 degrees of turn will be needed. Crossing runways may even need less turn. If the tailwind is 10-kts it will double the required runway for landing.

Best glide
Best glide is when parasitic drag and induced drag are the least. Induced drag decreases with airspeed, and is highest at low speeds as in slow flight. The best glide always occurs at the Angle of Attack that represents the best lift over drag ratio. This angle of attack is a constant, no matter how the aircraft is loaded.

By moving the CG aft, range) is increased, but glide is decreased. This means less downward lift required to counteract the CG and less load factor on the wings. The result is a lower angle of attack needed to maintain straight and level flight. The lower angle of attack allows airspeed to increase. With a faster airspeed we get an exponential rise in parasitic drag. This parasitic drag kills your glide.

At any AOA there's a parasitic drag, and an induced drag contribution to the total drag coefficient. Since the AOA is fixed at best glide, so, also, is the lift coefficient. There is only one factor that we can vary to adjust the lift to match any change in effective weight, the speed. Moving the CG aft, you reduce the second contribution, but leave the first unchanged. Whatever AOA, speed or lift coefficient you fly at, the overall drag coefficient is lower with an aft CG. If you fly the speed that gave best glide for the forward CG, you'll still get a better glide ratio with the aft CG. By flying a little slower you can get an even better glide ratio.

If the effective weight of the aircraft is decreased, while the angle of attack remains the same then the speed for that specific angle of attack must decrease. If the weight increases then the speed must increase to hold that most efficient L/D angle of attack. Adding ballast to a glider increases the penetration capability. The glide angle remains the same, but the speed to obtain that best glide angle increases with the weight. Your "glide angle" remains unchanged since as the weight increases your sink rate increases. Distance covered increases by exactly the same ratio.

Conventional aircraft carry a download on the tail for stability. Moving the CG moves aft reduces the download. This reduction in download acts like a decrease in weight. Since the download on the tail augments your pitch stability reduces your pitch stability margin. At some point the download reduction makes the aircraft difficult to fly. Approaching a stall quickly may make it impossible to get the nose to come back down.

Risk factors
--An airport near mountains
--Deficiency of RADAR coverage
--Non-precision approach
--Limited terrain lighting on approach path

Avoidance
--Maintain terrain clearance altitudes
--Descend only on published routes
--Identify navaids before using
--Cross-check your position
--Night is the most dangerous time.

 

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