CEN12LA095

The pilot's failure to maintain the recommended airspeed for icing conditions and his subsequent loss of airplane control while flying the airplane under autopilot control in severe icing conditions, contrary to the airplane's handbook. Contributing to the accident was the pilot's failure to divert from an area of severe icing. Also contributing to the accident was the lack of an advisory for potential hazardous icing conditions over the destination area.

The pilot obtained a weather briefing for the flight, during which light freezing drizzle was forecast for the proposed time and route. However, no advisories, either before or during the flight, were issued for the potential of hazardous icing conditions. The pilot stated that he had all of the airplane's deicing equipment on; however, the airplane accumulated moderate to severe airframe icing. The airplane was cleared for a GPS approach to the airport, and the pilot reported that he used the autopilot to fly the airplane to a navigational fix. An air traffic controller saw that the airplane was off course and subsequently canceled the flight's approach clearance. The copilot's window iced up. The flight was then cleared for another approach attempt, during which the pilot's window became "halfway iced up." The controller advised that the airplane appeared to be "about a half mile south of the course" for runway 25. The pilot configured the airplane with approach flaps and extended the landing gear before the final approach fix. The airplane descended under the cloud deck, and the pilot began to look for the runway. The pilot stated when he advanced the throttles, the airplane rolled about 90 degrees to the left. He disengaged the autopilot and attempted to use the yoke to level the airplane. The airplane then rolled about 90 degrees to the right. The pilot was unable to regain airplane control, and the stall warning horn came on seconds before the airplane impacted the ground. The pilot stated that he believed the loss of control was "primarily due to ice." The pilot stated that he maintained a target airspeed of 120 knots on approach, 100 knots "close to the ground," and was close to 80 knots when the airplane was in the 90-degree right bank. The airplane's recommended minimum airspeed for sustained flight in icing was 140 knots. The airplane's pilot operating handbook (POH) advises pilots to immediately request priority handling from air traffic control to facilitate a route or an altitude change to exit the icing conditions. Additionally, the handbook cautions the pilot that autopilot usage masks tactile cues, which indicate adverse changes in handling characteristics, and that use of the autopilot is prohibited when any specified visual cues exist in icing conditions. While the National Weather Service (NWS) issued an icing advisory over an area bordering the destination to the north, no NWS icing advisory extended over the area where the accident occurred. While the pilot would have been aware of potential icing from his weather briefings, he may not have expected the hazard due to the absence of an icing advisory over his route. If the pilot relied upon the graphic presentation provided in the icing advisory, which did not extend to his intended route, he may have been led to believe that he could accomplish the flight safely.

HISTORY OF FLIGHT On December 2, 2011, about 0810 central standard time, a Beech F90, N90QL, collided with terrain while on an instrument approach to the Midland Airpark (MDD), near Midland, Texas. The commercial pilot, who was the sole occupant, sustained serious injuries. The airplane was registered to and operated by Quality Lease Air Services LLC., under the provisions of 14 Code of Federal Regulations Part 91 as a positioning flight. Instrument meteorological conditions prevailed and an instrument flight rules (IFR) flight plan had been filed for the cross-country flight. The flight originated from the Wharton Regional Airport (ARM), Wharton, Texas, about 0626. The pilot obtained a weather briefing for the flight to MDD. The briefing forecasted light freezing drizzle for the proposed time and route of flight. While on approach to MDD, the airplane was experiencing an accumulation of moderate to severe icing and the pilot stated that he had all the deicing equipment on. According to the pilot, the autopilot was flying the airplane to a navigational fix called JIBEM. He switched the autopilot to heading mode and flew to the final approach fix called WAVOK. He deployed the deice boots twice before approaching WAVOK. An Airport Traffic Control Tower (ATCT) controller informed the pilot, that according to radar, he appeared to be flying to JIBEM. The pilot responded that he was correcting back and there was something wrong with the GPS. The controller canceled the airplane's approach clearance and the controller issued the pilot a turning and climbing clearance to fly for another approach. The pilot stated that his copilot's window iced up at that point. The pilot was vectored for and was cleared for another approach attempt. The pilot said that his window was "halfway iced up." About two minutes after being cleared for the second approach, the controller advised the pilot that the airplane appeared to be "about a half mile south of the course." The pilot responded, "Yep ya uh I got it." The pilot was given heading and climb instructions in case of a missed approach and was subsequently cleared to change to an advisory frequency. The pilot responded with, "Good day." The pilot had configured the aircraft with approach flaps and extended the landing gear prior to reaching the final approach fix. The pilot stated the aircraft remained in this configuration and he did not retract the gear and flaps. The pilot stated that he descended to 3,300 feet and was just under the cloud deck where he was looking for the runway. The pilot's accident report, in part, said: Everything was flying smooth until I accelerated throttles from about halfway to about three quarters. At this point I lost roll control and the airplane rolled approximately 90 degrees to the left. I disengaged autopilot and began to turn the yoke to the right and holding steady. It was slow to respond and when I thought that I had it leveled off the airplane continued to roll approximately 90 degrees to the right. At this time I was turning the yoke back to the left and pulling back to level it off, but it continued to roll to the left again. I was turning the yoke to the right again as I continued to pull back and the airplane rolled level, and the stall warning horn came on seconds before impact on the ground. The pilot stated he maintained a target airspeed speed of 120 knots on approach and 100 knots while on final approach. He stated he was close to 80 knots when the aircraft was in the 90-degree right bank. Witnesses in the area observed the airplane flying. A witness stated that the airplane's wings were "rocking." Other witnesses indicated that the airplane banked to the left and then nosed down. The airplane impacted a residential house, approximately 1 mile from the approach end of runway 25, and a postcrash fire ensued. The pilot was able to exit the airplane and there were no reported ground injuries. PERSONNEL INFORMATION The 53-year old pilot held a commercial pilot certificate with instrument airplane and airplane single and multi-engine land ratings. The pilot's most recent Federal Aviation Administration (FAA) second-class medical certificate was issued on August 3, 2011, with limitations for corrective lenses. The pilot reported having accrued 4,600 hours of total flight time and 25 hours of flight time in the same make and model as the accident airplane. He also reported that he had accumulated 224 hours of total flight time in actual instrument weather conditions and 5 hours of flight time in actual instrument weather conditions in the 90 days prior to the accident AIRCRAFT INFORMATION N90QL was a 1979 Beech, King Air, F90, twin-engine, T-tailed, seven-seat airplane with serial number LA-2. On June 6, 2011, the airplane received a phase three and four inspection. An airplane logbook entry in reference to that inspection showed that the Hobbs meter indicated 8,253 hours and the airplane's total time was the same. Two Pratt and Whitney Canada model PT6A-135 engines powered the airplane. Each engine drove their respective four-bladed Hartzell propeller. The airplane had two exits (viewed from the aft looking forward): the air stair door in the aft cabin on the left, and the overwing emergency exit on the right. The pilot reported that the airplane's maximum gross weight was 10,950 pounds and that the weight of the airplane at the time of the accident was 10,000 pounds. The airplane's maximum flap extension speed for the approach flap position was 184 knots indicated airspeed (IAS). The airplane's maximum landing gear extended speed was 184 knots IAS. According to the airplane's "Stall Speeds - Power Idle" chart, the calculated stall speed for the airplane weighing 10,000 pounds with approach flaps extended was about 81 knots IAS at zero degrees of bank and was about 114 knots IAS at 60 degrees of bank. The airplane's pilot operating handbook (POH) limitations section, in part, stated: ICING LIMITATIONS... Minimum Airspeed for Sustained Icing Flight...140 knots Sustained flight in icing conditions with flaps extended is prohibited except for approach and landings. ... LIMITATIONS WHEN ENCOUNTERING SEVERE ICING CONDITIONS (Required By FAA AD 98-04-24) WARNING Severe icing may result from environmental conditions outside of those for which the airplane is certificated. Flight in freezing rain, freezing drizzle, or mixed icing conditions (supercooled liquid water and ice crystals) may result in ice build-up on protected surfaces exceeding the capability of the ice protection system, or may result in ice forming aft of the protected surfaces. This ice may not be shed using the ice protections systems, and may seriously degrade the performance and controllability of the airplane. 1. During flight, severe icing conditions that exceed those for which the airplane is certificated shall be determined by the following visual cues. If one or more of these visual cues exists, immediately request priority handling from Air Traffic Control to facilitate a route or an altitude change to exit the icing conditions. a. Unusually extensive ice accumulation of the airframe and windshield in areas not normally observed to collect ice. b. Accumulation of ice on the upper surface of the wing, aft of the protected area. c. Accumulation of ice on the engine nacelles and propeller spinners farther aft than normally observed. 2. Since the autopilot, when installed and operating, may mask tactile cues that indicate adverse changes in handling characteristics, use of the autopilot is prohibited when any of the visual cues specified above exist, or when unusual lateral trim requirements or autopilot trim warnings are encountered while the airplane is in icing conditions. 3. All wing icing inspection lights must be operative prior t