by David Jack Kenny
Pilots of high-performance cross-country airplanes often view autopilots as more than mere conveniences. Many consider a fully functional autopilot a necessity for single-pilot flights in instrument conditions or at night. But of course an autopilot is only a collection of machines, themselves dependent on other machines, presenting a long chain of potential failure points: loss of electrical power to the computer or of attitude inputs after a vacuum failure, broken bridle cables, frozen or runaway servo motors, and so on. Autopilots may also kick themselves off line for reasons that aren’t immediately obvious. It stands to reason that a flight a pilot can’t safely conclude without relying on one is a flight that pilot shouldn’t make at all.
Shortly after 6 p.m. Mountain time on Nov. 19, 2013, a turbocharged Cessna T210M was destroyed by an in-flight break-up near Cedaredge, Colorado. The last radar return was recorded as it descended through 13,200 feet msl—about 5,000 feet above the ground—in a tight left turn. NTSB reconstructions suggest that its rate of descent increased to more than 20,000 feet per minute, causing an overload failure of the left wing spar. The outer 15 feet of the left wing was found a quarter mile from the fuselage.
The 57-year-old solo pilot had departed from Torrance, California almost three and a half hours earlier on a VFR flight to Grand Junction. He contacted Southern California Approach shortly after takeoff to arrange flight following, and within 10 minutes received approval to climb to his cruising altitude of 13,500 msl. The flight proceeded peacefully for the next two hours, during which the pilot left the frequency three times to get weather updates from Flight Watch.
At 6:01 p.m., the controller advised that the airplane appeared to be right of course, and the pilot replied that he’d decided to change his destination to Aspen. After confirming that the minimum IFR altitude in the next sector was 14,800, he left the frequency for a fourth time to pick up Aspen’s ATIS. Archived weather radar showed that at about that time, the Cessna entered an area of light precipitation; the NTSB subsequently concluded that it was dry snow, unlikely to pose any risk of ice accumulation. One minute after returning to Denver Center’s frequency, its pilot requested an IFR clearance.
His most recent medical application, filed eight months earlier, listed 1,560 hours that included 950 in type. His logbooks weren’t recovered, so his experience in actual IMC is not known, but he’d received his instrument rating a little over two years earlier. He copied routing via the Red Table VOR and began climbing to the assigned altitude of 15,000 feet, but needed a bit of prompting to supply the other information needed to complete a flight plan. Estimated time en route was given as 20 minutes with fuel on board for one hour.
After acknowledging that information, the controller observed, “Looks like you’re doing a 360-degree turn out there … Are you making it a long turn around toward Red Table?” The pilot responded, “No, our autopilot disconnected and so we’re recovering here.” The controller asked if he’d like an initial vector and the pilot said “That would be great,” but never read back the suggested heading of 040 degrees. Thirty seconds later the controller transmitted, “I just want to verify your altitude, showing you at one-three thousand two hundred.” There was no response. Less than four minutes afterward, a passing airliner reported hearing an ELT.
He was hardly the first pilot to lose control after unexpectedly finding himself hand-flying in IMC, and he probably won’t be the last. The NTSB attributed the in-flight break-up of a Pilatus PC-12 over Florida in June 2012 to the pilot’s response to an unexpected autopilot disconnect during a turn. Rather than stabilizing the aircraft first, he ran the autopilot test sequence, by the end of which the airplane was banked beyond 90 degrees and 175 knots above maneuvering speed. The Turbo Centurion pilot was fortunate in one respect: He didn’t take anyone else with him. The Pilatus pilot had his whole family on board.
Guiding the airplane through a climbing turn to a new altitude and heading shouldn’t be an insuperable challenge for any instrument pilot, day or night. Unease at the prospect of doing it without robotic assistance should provide a strong incentive to seek refresher training.