N886EA

History of Incident

On September 5, 2012, about 1041 Alaska daylight time (ADT, all times in this report are ADT unless noted), a Bombardier DHC-8-103, N886EA, experienced an uncommanded left roll and uncontrolled descent while climbing through about 12,000 feet mean sea level (msl, all altitudes are msl unless noted). The flight crew regained control of the airplane at an altitude of about 7,000 feet, and the flight returned to Ted Stevens Anchorage International Airport (ANC), Anchorage, Alaska. The 12 passengers and 3 crewmembers were not injured, and the airplane sustained minor damage. The airplane was registered to and operated by Era Aviation as flight 874 under the provisions of 14 Code of Federal Regulations (CFR) Part 121 as a regularly scheduled commercial flight. Day instrument meteorological conditions prevailed at the time of the incident, and the flight operated on an instrument flight plan.

The incident occurred on the third flight of a six-leg trip sequence for the flight crew. The flight departed ANC about 1029 and was enroute to Homer Airport (HOM), Homer, Alaska. The captain was the pilot flying (PF), and the first officer was the pilot monitoring (PM).

The incident flight release weather package showed a forecast for the area along the planned route of flight of occasional moderate turbulence below 12,000 feet above ground level (agl) and isolated moderate rime icing between 10,000 and 22,000 feet agl with a freezing level of 5,000 feet agl. The forecasts for both ANC and HOM were for broken to overcast skies with good surface visibility and gusty winds.

The flight was cleared to a cruise altitude of 10,000 feet. Both pilots stated in interviews that the captain engaged the autopilot when the flight reached an altitude of about 1,000 feet agl. The captain stated that he engaged the indicated airspeed (IAS) button on the advisory display unit and set a climb speed of 150 to 160 knots. Between 7,000 and 8,000 feet, the airplane entered a cloud deck and began accumulating ice, and the captain turned on the de-icing equipment. The first officer stated that the de-icing equipment was working normally and that ice was being shed from the propeller spinner, and the captain stated that the equipment was working normally but that it was not clearing all the ice off the airframe.

About 1037:24, the flight contacted the Anchorage Air Route Traffic Control Center. According to Federal Aviation Administration (FAA) air traffic control (ATC) recordings, the crew checked in with the Anchorage center sector 5 radar controller, stating, "we're with you level ten thousand and…just wanted to report…moderate mixed ice." At 1038:32, the crew requested a block altitude of 10,000 to 14,000 feet to try to avoid continued icing conditions, and the radar controller issued the clearance.

While commencing the climb, the captain initially set 14,000 feet in the altitude alert controller. The captain stated that he engaged the IAS button when he initiated the climb out of 10,000 feet and that he did not use the vertical speed (VS) mode during the flight. He could not recall the position of the throttles during the climb from 10,000 feet, but he noted that he did not manipulate them once he initiated the climb. Although the airplane was equipped with fast-slow type speed control indicators on each pilot's attitude director indicator (ADI), neither pilot reported looking at it. According to flight data recorder (FDR) data, during the climb, the initial airspeed was 170 knots, the climb rate was 850 feet/minute, and the engine power was not increased. The data showed a steady decrease in airspeed and a steady increase in altitude and pitch attitude for the duration of the climb.

The captain stated that, during the climb, he was monitoring the icing indications. The first officer stated that he was monitoring the de-icing panel; looking outside to make sure the de-icing boots were inflating and deflating in the proper sequence; and looking at the propeller spinners, windshield wipers, and windshield. The first officer said he was also getting ready to communicate with the arrival station and taking care of paperwork in preparation for landing.

Passing through about 11,500 feet, the flight began to emerge from the tops of the clouds, and the captain set the altitude alert controller to level at 12,000 feet. As the airplane began to level off, it began to shudder and the flight crew attributed it to an unbalanced condition of the propellers due to the uneven shedding of ice. According to FDR data, the airplane lost lift at 1041:18 as the airplane was climbing through 12,192 feet at an airspeed of 103 knots. The flight crew indicated that, shortly after, the shudder increased rapidly, the airplane rolled left, followed immediately by a pitch down. The FDR data showed that the left roll began at 1041:23 at an airspeed of 97 knots and reached a left bank of 47° in about 11 seconds. According to both pilots, no stick shaker warning activated before the airplane rolled. Stick shaker activation was not a recorded parameter on the FDR. After the airplane lost lift, the control column began to move back gradually from 3° to 8.5° over about 9 seconds increasing the pitch of the airplane to about 20° nose up. The autopilot remained on during this time. The captain opposed the left roll with control wheel input and the airplane recovered slightly before rolling further left to 55°.

The captain stated that he attempted to control the airplane by rolling it to wings level and pulling nose up, but he was unable to regain control. He added that he made a combination of control and power inputs, pushing the yoke and power forward and back as the airplane descended rapidly. FDR data indicated that the autopilot disconnected at 1041:26.7. At 1041:27 (about the same time the airplane reached its maximum altitude of 12,288 feet), the column was pulled back rapidly from 8.5° to 33° in 3 seconds.

The column was held aft at greater than 33° until 1041:43, at which time, the captain began to release the back pressure. The airplane pitch decreased from 20° nose up to 37° nose down during this time. FDR data further show that the captain did not attempt to push the column forward during the descent for another 7 seconds until 1041:50. At 1042:04 the airplane reached its lowest altitude of 7,072 feet and began to level out and stabilize after descending more than 5,200 feet in about 37 seconds. The flight made a left 270° turn during the uncontrolled upset event. Figure 1 is a graphical depiction of the flight path and altitude of the airplane at certain points during the loss of control portion of the flight.

Figure 1. A graphical depiction of the flight path and altitude of the airplane at certain points during the loss of control portion of the flight.

FDR data shows the engines were set about 70% of maximum torque when the airplane leveled off at 10,000 feet where they remained until the upset event. After the left roll, the engine power was reduced to about 30% of maximum torque for about 10 seconds before being increased above 100% exceeding the torque limitations. The engine power was reduced to about 90% before the airplane reached its lowest altitude and leveled off before being increased again further above 100% than previously.

The flight crew declared an emergency with ATC and requested a return to ANC. The flight crew landed the airplane at ANC uneventfully about 1056.

Personnel Information

The captain, age 41, held an airline transport pilot (ATP) certificate, issued April 30, 2012, with type ratings in Beechcraft BE-1900 (with the limitation that a second-in-command [SIC] was required) and DHC-8 airplanes. The captain held a first-class FAA medical certificate, issued May 17, 2012, with no limitations. The captain was hired by Era Aviation on November 27, 2000. According to the Era Aviation chief pilot, the captain was a DHC-6 Twin Otter first officer from November 2000 to June 2005, a DHC-8 first officer from June 2005 to November 2007, and a BE-1900 captain from November 2007 to May 2012. The captain stated in an interview that he upgraded to captain on the DHC-8 in April 2012.

According to Era Aviation and the captain's statements, the captain had accumulated 8,000 total flight hours, including 4,000 hours as pilot-in-command (PIC), 258 hours of which were as PIC in DHC-8 airplanes. A search of FAA records revealed no accident or incident history or enforcement actions regarding the pilot. The captain was disapproved for his initial commercial pilot certificate on January 11, 2000, for Area 8, "Emergency Procedures," but he successfully completed it on January 15, 2000. The captain was also disapproved for his initial flight instructor – instrument airplane certificate on May 17, 2000, for area 8, but he successfully completed the certificate on May 21, 2000.

An examination of Alaska State driving records indicated that the captain had 10 moving violations between February 2004 and April 2011. Five of these traffic violations were issued in the 3 years before the incident flight. On June 15, 2010, after the captain disclosed to the company that he had been in a traffic accident that was his fault, Era Aviation issued him a driving restriction that prohibited him from operating any company motor vehicles.

The first officer, age 44, held a commercial pilot certificate, reissued September 22, 2008, with a type rating in BE-1900 airplanes with SIC privileges only. He received his DHC-8 airplane type rating with SIC privileges only on November 19, 2010. The first officer held a first-class FAA medical certificate, issued June 21, 2012, with no limitations.

According to Era Aviation and the first officer's statements, the first officer had accumulated about 6,000 total flight hours, including about 2,360 hours as SIC in DHC-8 airplanes. From December 2004 to September 2007, the first officer flew Cessna 207 air...