WPR12FA040

The pilot's failure to maintain airspeed and airplane control while maneuvering in low visibility and icing conditions.

The pilot received two predeparture weather briefings, both of which reported that snow showers were expected over most of the state. During the second briefing, the pilot was advised that adverse weather conditions, including mountain obscuration, moderate icing, moderate turbulence, and low-level wind shear, existed throughout the planned route of flight. The pilot still decided to depart. As the airplane neared its destination, the approach controller issued the pilot vectors to the final instrument landing system approach course. The approach controller subsequently saw that the airplane was at 6,900 feet mean sea level (msl), which was 300 feet below the minimum vectoring altitude for the approach (7,200 feet msl). The approach controller issued the pilot a low altitude alert, and the pilot climbed the airplane back to the minimum vectoring altitude of 7,200 feet msl. About 1 minute after the approach controller transferred control of the flight over to the tower air traffic controller, the controller saw that the airplane was about 1/4 mile right of the inbound approach course. The controller then issued the pilot missed approach instructions, advising him to fly the runway heading and to climb and maintain 8,000 feet msl. The tower controller then transferred the pilot back to the approach controller, who advised the pilot that the runway visual range had decreased below that required for the approach. The pilot then elected to be vectored back to the final approach course to hold on the localizer until the weather improved. While he was issuing the pilot vectors to the localizer, the approach controller observed the airplane flying an inappropriate heading. After he advised the pilot of the irregularity, the approach controller issued a revised heading toward the localizer. The approach controller observed the airplane begin the right turn toward the assigned heading, and shortly thereafter, observed that the airplane was 1,200 feet below its assigned altitude. The approach controller issued the pilot another low altitude alert. There were no further radio communications with the pilot. The airplane impacted terrain about 8 nautical miles northeast of the airport, slightly left of the missed approach course, in a left-wing-low, steep nose-down attitude. About 2 minutes before the accident, the destination airport reported 1/2-mile visibility in moderate snow and freezing fog, with scattered clouds at 800 feet above ground level (agl) and an overcast cloud layer at 1,300 feet agl. Postaccident review of the weather conditions in the area at the time of the accident indicated that the pilot was operating in instrument meteorological conditions and that conditions were favorable for structural icing at a moderate to severe level. Postaccident examination revealed no evidence of preaccident mechanical malfunctions or failures that would have precluded normal operation. Based on the weather conditions that the pilot encountered while maneuvering near the destination airport, it is likely that the pilot failed to maintain adequate airspeed due to structural icing, which resulted in a loss of airplane control and subsequent impact with terrain.

HISTORY OF FLIGHT On November 18, 2011, about 1350 mountain standard time, N357, a Cessna 337G was substantially damaged after impacting terrain following a missed approach procedure at the Casper/Natrona County International Airport (CPR), Casper, Wyoming. The private pilot, the sole occupant of the airplane, was fatally injured. Instrument meteorological conditions prevailed for the personal cross-country flight, which was conducted in accordance with Title 14 Code of Federal Regulations (CFR) Part 91, and an instrument flight rules (IFR) flight plan was filed and activated at the time of the accident. The flight departed Rawlins Municipal/Harvey Field Airport (RWL), Rawlins, Wyoming, about 1315, with CPR as its destination. According to voice and radar data provided by the Federal Aviation Administration (FAA), while tracking the localizer inbound on the instrument landing system (ILS) to runway 03, the pilot was observed by the local tower controller to be about one-quarter mile right of track. At 1340:00, the controller informed the pilot of this condition, and requested that the pilot verify that he was aligned on the ILS for runway 03. The pilot responded, “Yeah. We’re having a little rodeo up here.” At 1340:11, the tower controller instructed the pilot to fly runway heading (030 degrees) and climb and maintain 8,000 feet for radar vectors around for another approach. At 1340:15, the pilot checked in with the approach controller, and informed him that he was on the missed approach. At 1340:28, the approach controller instructed the pilot to climb to and maintain 8,600 feet; the pilot confirmed the transmission. At 1341:47, the approach controller ask the pilot for the tower assigned heading, to which the pilot replied, “…uh, give me, uh, give me the heading again please.” The controller responded, "Skymaster three five seven, fly heading zero three zero. Turn left heading zero three zero." The pilot correctly read back the controller’s instructions. At 1343:27, the approach controller advised the pilot that the runway’s runway visual range (RVR) was currently two thousand, below the minimums for the ILS approach to runway 03, but that he would give the pilot a choice of either holding at Muddy Mountain, or he could vector him back around to hold on the localizer; the pilot chose to be vectored for the approach. At 1343:57, the controller instructed the pilot to turn left to a heading of 310 degrees for vectors to the runway 03 ILS approach; the pilot confirmed the heading as 310 degrees. At 1345:40, the controller instructed the pilot to turn left to a heading of 270 degrees, and again the pilot confirmed the heading. At 1346:58, the controller instructed the pilot to turn left to a heading of 220 degrees, and advised the pilot that the RVR was steadily increasing. At 1347:26, the pilot replied, “Okay. Could you say again. We’re, uh, we had a lot of squealing on the radio there.” The controller again instructed the pilot to turn left to a heading of 220 degrees, that the RVR for runway 03 was 2,800, that it looked to be increasing, and that he would advise him as he got closer to his base leg. At 1348:05, the approach controller advised the pilot of N357 that he had him tracking about a 130 degree heading, and to fly a downwind heading of 250 degrees for the ILS approach to runway 03. At 1348:17, the pilot replied, “Two five zero. Three five seven.” At 1348:35, the controller radioed to the pilot, “Skymaster three five seven. Low altitude alert. Check your altitude immediately. Minimum vectoring altitude (MVA) in your area is seven thousand five hundred. Climb and maintain eight thousand six hundred. Are you having trouble maintaining altitude?” There were no further transmissions from the pilot. About 1 minute later, radar contact was lost with the airplane and attempts by ATC to make contact by radio were unsuccessful. The airplane was located about 8 miles northeast of CPR in a snow-covered area of gently rolling terrain with sparse vegetation. A survey of the wreckage, which had come to rest upright in a tightly confined area, revealed that all major components of the airplane were accounted for at the accident site. The airplane had been consumed by a postcrash fire. A FAA aviation safety inspector assigned to the FAA’s Flight Standards District Office in Casper, reported that he was one of the first responders to the accident site. The inspector stated that due to the thermal distress that the airplane had sustained, there was no evidence of any ice accumulation on any part of the airplane. Subsequent to the onsite documentation of the wreckage being completed, the airplane was recovered to a secured storage facility for further examination. PERSONNEL INFORMATION The pilot/co-owner, age 61, held a private pilot certificate with airplane single-engine land, multiengine land, and instrument airplane ratings. The pilot’s most recent logbook entry, dated February 18, 2011, revealed a total time of 4,582 hours, 4,487.8 hours of which was pilot in command. The pilot logged 702 hours of airplane multiengine time, 3,843 hours of airplane single-engine time, and 687.3 hours in the make and model of the accident airplane. Additionally, the pilot recorded 644.7 hours of actual instrument time and 648.9 hours of night time. A further review of the pilot’s logbook revealed that his most recent instrument approaches, 10, had been completed in a simulator on February 15, 2011, while attending training at the facilities of Recurrent Training Center, Inc., Savoy, Illinois. This training was documented with a signed off sticker placed in the back of the pilot’s logbook. Personnel at Recurrent Training Center refused to provide training records consistent with the training provided to the pilot on February 15, 2011. Additionally, and subsequent to the training being satisfactorily completed, on February 15, 2011, the pilot logged a 4.9 hour cross-country IFR flight from the University of Illinois-Willard Airport (CMI), Champaign/Urbana, Illinois, to the North Platte Regional Airport (LBF), North Platte, Nebraska, during which the pilot logged 1.0 hours of actual instrument flight time; no instrument approaches were noted during this flight. From the pilot's last logbook entry on February 18, 2011, up to the date of the accident, which occurred almost 9 months to the day of his last logbook entry, the pilot's logbook contained no other entries of instrument flight time or of instrument approaches being completed. The co-owner of the airplane provided additional documentation, which indicated that from March through the end of October, 2011, the accident pilot had accumulated a total of 40.3 hours in the accident airplane. However, there was no breakdown of flight time in instrument meteorological or visual meteorological conditions. The data provided indicated that the pilot flew the accident airplane about 12 hours in the last 90 days, 1.2 hours in the last 60 days, and no flight time in the 30 days preceding the date of the accident. FAA records indicated that the pilot's most recent third-class airman medical certificate was issued on May 6, 2011, with the limitation that the pilot "must wear corrective lenses." AIRCRAFT INFORMATION The pressurized, in-line thrust airplane was manufactured in 1976. It was being operated with a standard airworthiness certificate in the normal category. The airplane was equipped with two Continental TSIO-360-series engines, each rated at 225 horsepower, and McCauley two-bladed, constant-speed propellers. The airplane was on an annual inspection maintenance program, which was last performed on April 5, 2011, at a total airframe time of 3,187.1 hours. Aircraft maintenance records revealed per a logbook entry dated September 30, 2011, that the rear engine, serial number 1000310, and the front engine, serial number 824819-R, had accumulated a total