Hands Full

Sometimes, in-flight emergencies can overload us. We have to take control of the situation.

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Flying a personal aircraft is different things to different people. To some, its fun, relaxing recreation. To others, its an efficient, private transportation mode. It can be just a job, or a career or a reason for living. Thats when things are going well.

Of course, when were living right, the sun shines, the engines hum, ATC clears us direct to our destination on initial climb and the woman behind the FBO counter at our destination turns out to be the just-divorced head of our high schools cheerleading squad.

When things are going badly and the airplane soils the bed, however, flying becomes less than fun, less than mere transportation and much more than a job. Suddenly, its a chore, a measure of how well we can cope with the unexpected. Some of us excel at handling crises; some do not. Often, people and pilots can go for years without ever having confronted the kind of life-threatening challenges others face with frustrating regularity. And, thankfully, modern airplanes are extremely reliable; on the rare occasions when something goes wrong, your training kicks in, you resolve the problem and you move on.

Thats when only one thing goes wrong. Sometimes, though, were faced with multiple failures, one cascading after another, or a situation where a mechanical problem brings with it a substantially higher workload, imposes operational limitations or all of the above. For example, trying to fly a heavy piston twin and deal with an engine failure, an emergency landing gear-extension procedure, airframe ice and an instrument approach, all at the same time. Surely, it can be done but, equally certain, some of us may fail to manage the crisis.

The training we undergo initially and throughout our flying careers should have prepared us for every eventuality, and even combinations of problems we might experience. And we read this magazine each month to learn about the bad things that can happen and how to handle them. Sometimes, though, none of it is enough.

Background

On December 28, 2004, at 1135 Central time, a Piper PA-23-250 Aztec flown by a Commercial pilot with Instrument and multi-engine land ratings was substantially damaged when it collided with terrain at the Gogebic-Iron County Airport (IWD) in Ironwood, Mich. The pilot and four passengers sustained fatal injuries. The pilot had reported an engine problem about 20 minutes before the accident while en route to IWD.

The flight was on an IFR flight plan until the pilot canceled IFR while on approach to IWD and proceeded VFR. Visual conditions prevailed at IWD under a low overcast through which the Aztec had to descend to find the airport. The flight departed the Menominee-Marinette Twin County Airport (MNM) in Menominee, Mich., at about 1010.

At 1104, after a routine flight, ATC cleared the pilot to descend at his discretion to maintain 3500 feet msl. Earlier, he was advised to expect vectors for the ILS Runway 27 approach at IWD. At 1114:58, the pilot notified ATC he had lost an engine and declared an emergency. At the time, IWD was the closest airport.

Radar data depicted a wild ride. At one point, the calculated average descent rate was 2500 fpm and the average rate of course change was seven degrees per second a standard-rate turn is three degrees per second. The aircraft descended below radar coverage at 1120:35.

At 1127:07, the pilot reported the runway was in sight and, at 1128:00, he reported a “complete loss of hydraulics” to ATC. The pilot added he was planning to circle to the left and hand pump the landing gear down. No further transmissions were received from the accident aircraft.

The accident site was wholly within the side yard of a residence south of the IWD airport. A line of trees about 40 feet high was 19 feet west of the accident site, oriented in a north-south direction. No evidence of a tree strike was observed and snow on the tree branches appeared undisturbed.

Investigation

The Aztecs left engine had failed before the crash; the right engines propeller exhibited signs of developing power at impact. Examination revealed the left engines #4 cylinder had fractured completely in the threaded area of the cylinder head. The flaps were up; the main landing gear was extended. Ice was present on the leading edges of the wings, stabilator, vertical stabilizer and antennas.

Although the left engine had apparently at least partially failed, its propeller had not been feathered. Examination revealed the quantity of oil drained from the propeller hub cylinder would not have been present had the propeller been feathered at the time of impact. Additionally, no witness marks due to the pitch change mechanism were observed at or near the feather position.

The Piper Aztecs flaps and landing gear are hydraulically actuated by a pump mounted on the left engine there is no pump on the right engine. In the event of left engine failure, the emergency hydraulic hand pump is used to supply hydraulic pressure. A CO2 system can be used for landing gear extension.

Probable Cause

The NTSB determined this accidents probable cause to be: “Fatigue fracture of an engine cylinder resulting in a loss of power on the left engine. Additional causes were the pilots failure to maintain minimum control airspeed (Vmc), the resulting loss of aircraft control, and an inadvertent stall/spin. Contributing factors were the pilots failure to feather the propeller on the failed engine and his decision to turn toward the inoperative engine during the circling maneuver. Additional factors were the inoperative hydraulic system pump and the emergency landing gear actuation which caused the pilot to circle prior to landing.”

This guy had a bunch on his plate. While a failed engine is certainly an emergency, it is manageable, especially when within range of the destination. But he still had to shoot an ILS, lower the landing gear and decide whether to lower the flaps. He also had at least a small amount of ice, which probably increased both the stalling and Vmc speeds.

He came close to losing control at least once, and never fully feathered the failed left engine, perhaps allowing it to windmill in the hope its hydraulic pump would lower the gear.

Sometimes, we can get in over our heads. There can be too many things to do, in sequence, and not enough time to do them. This pilot had his hands full. When it happens to you, dont let events control the outcome; you have to control events.

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