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The worst possible moment

 

The worst possible moment for an engine failure is just after take-off. There is no time to think about what must be done. We have to be able to react instantly to avoid a stall, and to get the aircraft (and ourselves) onto the ground with minimum damage.

The pilot of a C-172 reported engine power was lost at about 400 feet. The Tower Controller reported that the aircraft entered a steep descent and appeared to be attempting to land on the remaining runway. The aircraft levelled off just above the runway momentarily, pulled up and entered a steep left turn. The aircraft stalled and crashed, killing all three people on board.

At about 300 feet above ground, the Mooney 20F was seen to roll abruptly to the left and enter a spin. The aircraft crashed about 75 feet from a house. The pilot and 3 passengers all died. Water was found in the fuel system and corrosion was found in the engine-driven fuel pump and in the fuel filter.

The Piper J3C-65 took-off after a brief stop for a radio antennae repair. At about 200 feet, the engine lost power and the pilot began a steep 180 degree turn. The aircraft stalled and spun into the ground just off the departure end of the runway. The fuel shut off valve was found in the "off" position.

It was found that it is possible in this aircraft type for the engine to run for as long as one minute and 45 seconds with the fuel shut off valve in the "off" position.

When an engine fails on a single engine aircraft, it is imperative to lower the pitch attitude of the aircraft to a glide attitude immediately, attain the recommended glide speed, and find a place to land, in that order.

When an engine fails just after take-off, the temptation is to try to make it back to the airport. Unfortunately, many of these attempts end in disaster. When the pilot realizes he/she may not be able to glide far enough, they raise the aircraft pitch attitude to try to lengthen the glide. This actually results in an increased rate of descent, and could result in a stall if the nose is raised high enough.

The aircraft published glide speed is the best/lift drag ratio in a power off glide. Raising the aircraft pitch attitude above the attitude required for the best glide speed will result in increased induced drag and an increased rate of descent.

Published Cessna materials say that a 180 degree turn in a glide can be accomplished in 500 feet. As most C-150/152/172 aircraft glide at about 500 feet per minute in wings level flight, we can assume the turn Cessna is talking about is accomplished in a shallow turn. Increase the angle of bank and the rate of descent will increase. A turn back to the runway will almost always result in an increased angle of bank beyond a gentle turn. Most Cessna flying instructors advise to not attempt a 180 degree turn to the airport unless you are well above 500 feet, at least 600 feet AGL.

Other aircraft types will have a different rate of descent at the published recommended glide speed. A good rule of thumb to follow is to take the aircraft rate of descent for one minute and add at least 100 feet for the minimum 180 degree turn altitude.

The pilot of a PA 28-140 Piper Cherokee that has a rate of descent of 600 to 700 feet per minute should not attempt to try a 180 degree turn in a glide unless he/she is above 800 feet AGL.

Airports with crossing runways offer more opportunities. It may be possible to return to a runway without turning 180 degrees. Turning tightly to do it is not recommended, however, due to the possibility of a very high sink rate or a stall.

The J3 pilot and C-172 pilots proved once again that a steep turn without engine power is a bad idea. The Mooney pilot did not maintain a safe airspeed.

As mentioned earlier, the first thing to do when you realize the aircraft engine has lost power at very low level is to lower the nose pitch attitude to the glide attitude and attain the recommended best glide speed. If you are below the return to the airport altitude, pick a landing site within 30 degrees of the aircraft nose, declare a MAYDAY and perform the emergency aircraft shutdown checks if time permits.

If the altitude is adequate and the decision is made to return to the airport, fly a coordinated descending turn. The departure was likely made into wind. The turn from into wind to down wind in a descending turn, at slow speed may give rise to the illusion of a slip. Check the instruments to confirm you are in a coordinated turn.

If you don’t, you may try to correct for the illusion by applying more rudder in the direction of the turn, and by raising the nose of the aircraft. The added rudder will tighten the turn and increase the rate of descent, which in turn will increase the tendency to raise the nose. The result of this scenario will be a stall with yaw, in other words, a spin.

When turning back to the airport, the tendency is to try to make a runway. This may cause you to try to stretch the glide, or to turn more tightly. It may be better in many circumstances to try for a landing in the infield.

Keep the wind in mind. After turning, you may have a strong tail wind and a fast ground speed on landing. If you have turned less, or more, than 180 degrees, you may have a strong crosswind that uncorrected for, may take you in directions you would rather not go.

Spend a little time thinking about what you would do if the engine in your aircraft decides to take a holiday at the worst possible moment, and review your procedures periodically.

Pilots of commercial multi-engine aircraft with two crew are required to brief engine out after take-off procedures before every take-off. This might not be a bad idea for all of us. It can be done silently. This mental preparation will make a significant difference in our performance in the event that the worst case happens.

Dale Nielsen is an ex-Armed Forces pilot and aerial photography pilot. He lives in Abbotsford, B.C., and currently flies air charters. He still freelances as a flying instructor and seminar facilitator. Nielsen is also the author of seven flight training manuals published by Canuck West Holdings.

Got an aviation safety story to tell? Dale Nielsen would like to hear from pilots who have educational aviation experiences to relate. Excerpts from these stories will be used in upcoming safety articles. Dale can be contacted via e-mail: dale@flighttrainingmanuals.com.