15 critical seconds

The solo pilot with no passengers on board powered up, started rolling, and triggered countdown for the final 34 seconds of his life. Four seconds after rotation with the aircraft at 105 knots—about 19 knots above minimum controllable airspeed—the aircraft slowed, descended, and yawed to the left in a slight left turn, signs that the aircraft experienced a significant loss of thrust on the left engine. The powerful King Air 200 pitched down slightly, and the aircraft briefly yawed right with a slight right roll, almost certainly signs the pilot responded with right rudder and reduced pitch. Airspeed continued to decay. Pitch then increased to 15 degrees and the King Air quickly rolled right 13 degrees, then rapidly rolled over to 86 degrees of left bank, 73 degrees nose down, and hit the ground. The pilot died in a scenario that, ironically, he’d prepared pilots to address through training at the King Air Academy in Phoenix, Arizona, which he founded.

The focal point of multiengine training is engine failure, and the most crucial phase of flight—for which multiengine pilots are repeatedly trained—is the critical 15-second window between rotation and gear retraction. Should thrust go amiss in this window, pilots must correctly and promptly identify, verify, and respond to the problem. Poor analysis or an erroneous or delayed response have devastating consequences. On-board systems data indicate about six seconds from the time the pilot experienced a loss of thrust until the aircraft became uncontrollable.

The NTSB could not determine the cause for left engine thrust reduction. Teardown of both engines and inspection of both propellers revealed nothing beyond damage associated with the crash impact. Investigators could not determine the position of power and propeller levers at the time of thrust loss, although the inspection seemed to indicate power levers full forward at impact and propellers not in feather.

The aircraft was on its first flight after maintenance, which became an immediate area of interest. Inspection of maintenance logs, however, revealed no unresolved issues, nor did recent work seem a likely source of the thrust problem. With systems and equipment analysis exhausted with no suspicious evidence, and given day VFR weather with clear skies and 10-knot winds, the focus turned—as it does some 75 percent of the time—to human factors: actions the pilot took, or didn’t take, and the decisions he made that might have triggered a sudden thrust reduction or caused the subsequent loss of control.

Investigators found a few pre-takeoff oddities, such as rudder trim four notches to the left and aileron trim six notches to the right. An odd alignment, but not by itself overly problematic. King Air pilots in the simulator with these settings noticed some aircraft response to the settings but found them easily controllable on takeoff. More significantly, the accident pilot did not turn on rudder boost, which helps the pilot with aircraft control in exactly this scenario. It’s impossible to know what effect the rudder boost might have had in assisting with aircraft control, but it almost certainly would have helped.

The Before Engine Start checklist for the King Air specifies that rudder and aileron trim are set and rudder boost on. Taken together, the trim and rudder boost settings indicate gaps in the pilot’s pre-takeoff checklist adherence and mental preparation. It was a quick, easy repositioning flight home in clear weather. Did the pilot get complacent, was he in a hurry? Such short flights can be a problem in aviation. We establish a more relaxed posture, expecting a short, easy flight, when in reality we will experience most of the risk elements of a longer mission and must accomplish the same critical flight actions, only in a condensed time period. Thrust loss on takeoff is a crisis that you must be ready to manage, regardless of the length of your flight.

he powerful King Air 200 pitched down slightly, and the aircraft briefly yawed right with a slight roll.It takes about 20 seconds for a mental review of thrust loss on takeoff and the appropriate response actions, touching the knobs and switches you will confirm and actuate. It’s a concept psychologists call “priming”—refreshing mental cues for subconscious preparation so that you are mentally ready and your actions are smooth, deliberate, and correct.

The pilot’s switch errors, combined with no evidence of engine or propeller problems, call into suspicion the King Air’s power control friction knobs as cause for the left engine thrust loss. Friction knobs are a known issue in King Airs, and this pilot would certainly have been aware of the importance of tightening them prior to takeoff. The NTSB couldn’t confirm friction settings because of the post-crash damage, so we don’t know for certain, but circumstantial evidence points to loose friction knobs and throttle or propeller lever rollback as a possible cause for the thrust reduction. This kind of thrust rollback tends to happen during rotation as the nose pitches up, right about the time this pilot lost left engine thrust. Such an incident would leave no signs of engine malfunction.

We’ll never know for sure what caused the sudden loss of thrust in this King Air in the critical 15-second window; and we’ll never fully understand why the pilot lost control of the aircraft despite being 19 knots above minimum controllable airspeed when thrust was lost. Despite these unknowns, this tragedy reinforces the critical 15-second window in multiengine aircraft on takeoff, and the imperative that we’re ready for it on every takeoff through thorough pre-takeoff checklists and by taking 20 seconds to “prime” ourselves for takeoff contingencies and a correct, prompt response.

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