History of Flight
On January 2, 2010, at about 1521 eastern standard time, a Fairchild SA227 Metro III, registration N227ML, operated by Locair, Inc. as flight 151, veered off the side of runway 23 during the landing roll at Lake Cumberland Regional Airport (SME), Somerset, Kentucky. The flight was conducted under 14 CFR Part 135 as an on-demand air taxi with an IFR flight plan. Visual meteorological conditions prevailed at the time. The flight originated from Baltimore/Washington International Thurgood Marshall Airport at 1320.
The pilot-in-command (pilot flying) reported a stabilized approach and normal touchdown with main landing gear first, followed by the nose gear. As the nose wheel contacted the runway, the airplane veered right. Despite applying full left rudder and full reverse on the left power lever, the pilot could not correct the alignment. Engaging the nose wheel steering button resulted in a more aggressive right turn. The aircraft departed the runway, traveled down an embankment, and came to rest against the airport boundary fence.
The co-pilot (non-flying pilot) stated that after touchdown, the pilot-in-command moved the power levers to reverse, and the airplane suddenly turned right. Despite efforts including full reverse on the left engine, the aircraft continued right and exited the runway, sliding down the embankment and striking the fence.
A Locair customer service representative witnessed the approach from the tarmac. She observed a normal touchdown followed by taxiing. At the point where a turn toward the terminal was expected, the airplane began to fishtail, then straightened and went off the runway.
Another witness noted the airplane touched down beyond the 3,000 feet remaining marker for runway 23 and that the AWOS reported wind from 330 degrees.
Personnel Information
The pilot flying, aged 41, held an airline transport pilot certificate with multiengine land rating, a flight instructor certificate, and a first-class medical certificate issued December 6, 2009, at which time he reported 5,350 total flight hours.
The pilot monitoring, aged 33, held a commercial pilot certificate with single and multiengine land and instrument ratings, and a first-class medical certificate issued August 8, 2008, reporting 350 total flight hours.
Aircraft Information
The Fairchild SA227 Metro III, manufactured in 1982, was equipped with two Airesearch TPE331-11U turboprop engines. It was maintained on a continuous airworthiness inspection program; the most recent inspection was completed on December 3, 2009, at 25,945 total aircraft hours. At the accident time, the aircraft had accumulated 25,998 hours.
According to the Metro III Landing Distance Chart in the Airplane Flight Manual, an airplane with a landing weight of 11,000 pounds required approximately 2,600 feet of landing distance given the wind, temperature, and elevation conditions present.
Meteorological Information
Weather recorded at SME at 1515 included wind from 310 degrees at 5 knots, 10 miles visibility with light snow, overcast clouds at 2,500 feet, temperature -7°C, dew point -11°C, and altimeter setting 30.34 inches of mercury.
Airport Information
Lake Cumberland Regional Airport had a single runway oriented 5/23, 5,800 feet long and 100 feet wide, made of asphalt. A post-accident visual inspection by the airport manager revealed no water, ice, or snow on the runway. A friction test yielded 71% friction on the first third, 64% on the second, 51% on the third, and an overall average of 62%.
Wreckage and Impact Information
Examination of the runway by an FAA inspector revealed tire marks from all three landing gear, beginning just past the 2,000 feet remaining sign. The marks tracked straight without skidding for 120 feet, then curved right. The curve continued for 285 feet before exiting onto grass. The markings continued through grass until the left propeller struck the Taxiway D intersection sign, then crossed Taxiway D and Taxiway A, and continued down an embankment, terminating 1,131 feet from the initial marks where the airplane struck the fence. All runway markings were friction transfer, not skid marks, indicating rolling tires without locked brakes.
Examination of the aircraft revealed substantial damage to the right wing outboard of the landing light, with accordion crushing. The left propeller had two of four blades damaged from contact with the taxiway sign; all four blades had curled tips from striking rocks. The two damaged blades were locked in low pitch; the other two were free-moving. The right engine propeller was feathered with all blades damaged. The nose section sustained scratching from fence contact but was not compromised. Flaps were partially extended.
Cockpit examination showed the nose wheel steering switch in the "ARMED" position, engine power levers between ground idle and reverse (right lever stiffer than left), and flap control between 1/4 and 1/2. The landing gear assemblies appeared undamaged; tires were inflated and undamaged.
Tests and Research
Engine examination revealed the right power lever was stiff and difficult to operate even with minimal friction locks, while the left operated smoothly. Rigging checks showed the right engine led the left by 8–10 degrees, possibly indicating the right engine entered reverse before the left.
The left landing gear brake underwent operational bench testing and teardown; no defects were noted.
The nose landing gear (NLG) steering actuator was also operationally tested and visually inspected. The reported failure could not be duplicated, and the hydraulic fluid was in "like new" condition with no contamination.
After the accident, Locair maintenance advised that a connection had been repaired and the nose wheel steering appeared to function normally. The NTSB requested an FAA observer for taxi testing. During the test, the AMT taxied and applied brakes; the NWS responded appropriately. Subsequent tests at increasing speeds (20, 35, and 50 knots) were conducted. At 50 knots, application of brakes caused a sharp right turn; despite left brake and NWS engagement, the aircraft exited the runway. The AMT reported inability to steer. After this second excursion, further examination revealed damaged wires in the NLG steering harness. The harness was rewired, reinstalled, and operationally tested with no further anomalies.