Wicked Assumptions

Think before you saddle up for what you expect to be a routine flight

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Roy Rogers had Trigger; the Lone Ranger had Silver. And each of them knew they could count on their horse to help them out of a jam. They knew the horse would always be up to snuff. They knew if the horse could jump that ravine or catch that steaming locomotive. Of course, it always would.

Similarly, pilots put a lot of faith into their trusted steeds. After a while flying the same airplane, rotation comes by feel and sound, with sometimes only a cursory glance at the airspeed indicator. Landings at familiar fields are made without second thought.

While that may not be unsafe, sometimes the shortcuts can be more onerous. Some pilots have virtually abandoned weight and balance calculations, having discovered long ago that their bird will fly when the suitcases only come up to here. They eyeball the passengers and guess their weight. They routinely order the tanks topped, without regard to the load they may carry on the next flight.

And then there are the issues of technique. I recall transitioning into a high performance airplane in which the instructor ordered up a certain airspeed over the fence. Try as I might, bounces seemed the norm rather than the exception. It wasnt until later that I discovered the instructor was deathly afraid of stalls and routinely added 10 knots to the approach speeds he suggested students use.

Familiarity with the airplane and the route you intend to fly are good things, but like cognac and chocolate, can be taken to extremes that are decidedly unhealthy. Unlike Tontos kimo sabe, who never expected more of the horse than the horse could deliver, some pilots ask a little too much at exactly the wrong time.

One September afternoon a pilot and his student-pilot son boarded a Citabria 7GCBC for a planned 76 nm flight from Telluride, Colo., to Grand Junction, Colo. The weather was clear and the pilot had neither gotten a weather briefing nor filed a flight plan.

The pilot in command held a commercial license, an instructors certificate and single, multi and instrument ratings. He had more than 12,000 hours total time, including about 150 hours in the Citabria and nearly 3,000 in taildraggers.

Preflight included fueling the airplane with 12 gallons of fuel, bringing the total on board to 36 gallons. The pilot yielded the front seat – the seat approved for solo flight – to his son and he took the back seat. Both seats were equipped with flight controls, although the front seat occupant would block the pilots view of most of the instruments and the view out the windshield.

When the pilot attempted to start the engine, the battery did not live up to the task. The pilot got out and hand-propped the engine, then the pair taxied out to the runup area for runway 27.

Meanwhile, a Mesa Airlines pilot taxied the airlines Beech 1900 to the runup area where the Citabria was conducting the usual pre-takeoff checks. The commuter plane held while the pilots contacted Denver radio for their IFR clearance.

During this period, the small taildragger stated that he was ready to go and was going to go ahead of us, the pilot of the turboprop said. I gave him a thumbs-up and asked what his direction of flight was going to be. He replied and said he would be straight out and advised me that he would remain north. I watched as he took position on runway 27 and began his takeoff roll.

A direct heading toward Grand Junction would have been 326, making it unclear in retrospect exactly what the pilot meant by heading straight out. Perhaps it meant he was planning to fly something other than a direct route to his destination. It may also have meant he was departing the airport area on more or less a runway heading before turning en route.

Although the pilot of the Beech lost sight of the Citabria during its takeoff roll, the co-pilot did not. He said the aircraft made what appeared to him to be a very unusual maneuver.

An aircraft line technician recalled the initial path of the airplane: I saw the Citabria become airborne in a short distance on runway 27, and immediately begin banking to the north. There is a low hill just west of the airport terminal which runs generally south to north and limits the view in that direction. The Citabria disappeared from my view, west of the hill, still headed in a northerly direction. When I last saw it, the aircraft appeared to me to be in a nose-high attitude but not climbing.

Though the line tech volunteered that he is not a pilot, he added that the departure was significantly different from the numerous other takeoffs he sees every day.

Another witness was a student of the pilots and had been present when the pair boarded the plane for departure. She said the Citabria took off about 2,000 feet down the 6,870-foot runway and flew down the centerline of the runway for another 2,000 to 3,000 feet. At that point, the Citabria banked right and leveled off, then banked steeply right and passed out of view behind the hill.

The Beech, meanwhile, had completed its takeoff final items checklist, announced its intentions over Unicom and departed. Just after the aircraft took off, the co-pilot saw the Citabria down in a ravine. There was no smoke, no fire. The Beech pilot immediately radioed the information to the Unicom operator. Soon, rescue teams were on the way.

The Citabria went down between 16:15 and 16:18, when a 911 call was recorded. The first rescuer on the scene was the line technician who had fueled the airplane. It took him about 20 minutes to reach the site.

There was no fire, though there was some fuel leaking from the wreckage, he told investigators. I was able to check for a radial pulse on both occupants of the aircraft and made a preliminary determination that neither had a pulse. Very shortly, [two EMTs] arrived and confirmed that neither occupant had a pulse.

The Telluride airport has an elevation of 9,078 feet, and the density altitude at the time of the crash was computed to be 10,900 feet msl.

Evidence began to mount that this was something more than a classic high density altitude departure stall accident.

When investigators began a weight and balance study, they used the most recent empty weight calculation for the airplane, the weights of the two occupants at their last FAA medical exam, and an estimated weight of two small backpacks found in the wreckage. The empty weight of the plane was 1,193 pounds and its maximum gross weight was 1,650 pounds, which left 457 pounds for fuel, passengers and baggage. With 36 gallons of avgas aboard, the useful load was down to 241 pounds. The pilot weighed about 210 pounds and his son about 230. The two backpacks added another 20 pounds.

All told, the airplane was 219 pounds overweight when it tried to claw into the thin high-altitude air. Even though the center of gravity was within limits, the result was perhaps predictable.

Shortly after the accident, another party came forward with another piece to the puzzle. An FAA designated pilot examiner who operated a glider tow business said the accident pilot was one of his tow pilots. He said the accident pilot routinely used high-performance takeoffs when operating tailwheel airplanes. He would hold full aft stick during the takeoff roll, lift off nose high and climb with a steep angle of attack.

The pilots son had confided to the glider operator and the witness who saw them off that he was apprehensive about routinely using the soft-field takeoff technique, especially in high-density altitude conditions.

Like most accidents, this one was caused by a variety of factors, without any one of which the accident chain may have been broken. Maybe the overweight airplane would have tolerated the high altitude with a normal takeoff technique. Maybe not.

The bottom line is that the pilot demonstrated a lack of respect for the airplanes limitations. Most of his recent hours had been in a Mitsubishi MU-2 turboprop, which he flew frequently for the owner, a local businessman. Perhaps he underestimated just how far down the performance ladder the Citabria actually fell.

In any case, his disregard for the limitations of the airplane he was flying directly resulted in this accident. In other words, he let down the horse; the horse didnt let him down.

Pilot attitude is difficult to teach. It can vary tremendously from day to day and mood to mood. Yet it is probably one of the biggest causes of aviation accidents. Its one thing to know what youre supposed to do, quite another to actually do it.


-by Ken Ibold

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