Washington

About 14 minutes after departing on the cross-country flight in instrument meteorological conditions, the airplane was observed on radar climbing through 14,800 feet mean sea level (msl). At this time, the pilot radioed to air traffic control (ATC) that he was returning to the departure airport. About 7 seconds later, the pilot transmitted that he had lost an engine and again stated that he was returning to the departure airport. About 50 seconds later, the pilot transmitted, “We’re losing it.” There was no further communication with the pilot. Radar data revealed that at 14,800 feet msl the airplane began a right 360-degree turn at 8 degrees per second, and about 120 degrees into the turn, it began a descent averaging 5,783 feet per minute. The airplane remained in a right turn until radar contact was lost at 10,700 feet msl. The airplane impacted a 30-degree slope of a densely forested mountain about 2,940 feet msl in a near vertical, slightly right-wing-low attitude. A logger working in the area reported hearing a “very loud roaring sound,” like an airplane diving toward his location and that it seemed to be “really under power.” The logger described the weather as being “socked in,” with light rain and not much wind. Post accident examination revealed that propeller damage was the result of impact forces, with no indications of fatigue or propeller failure before impact. It was also noted that the left propeller was being operated under conditions of some power at impact, while the right propeller was not operating under conditions of significant power at impact. Based on these findings, it is most likely that the pilot experienced a partial loss of power of the right engine and, after incorrectly initiating a right turn into the failed engine, allowed the rate of turn to increase to the point that the airplane became uncontrollable before impact with terrain. The reason for the partial loss of engine power was not determined because postaccident examination of the airframe and both engines did not reveal any mechanical malfunctions or failures that would have precluded normal operation.

The amphibious-float-equipped airplane departed from a paved runway for the 40-nautical mile flight to its destination, where a water landing on a lake was to be made. The pilot did not raise the landing gear after takeoff. During the flight, the air was bumpy and turbulent, and this resulted in the gear advisory system activating numerous times. The purpose of the system is to alert the pilot of the landing gear position--up for a water landing or down for a runway landing--when the airspeed decreased below a set threshold value. The pilot disabled the system by pulling its circuit breaker because the alerts were becoming a nuisance; he intended to reset the breaker during descent, but did not do so. Upon reaching the destination, the pilot set up a 150- to 200-feet-per-minute rate of descent for a glassy water landing on the lake. With the landing gear in the down position, the airplane contacted the water and abruptly nosed over. The airplane came to rest floating inverted, suspended by the floats. The pilot reported that the day of the accident was his nineteenth consecutive duty day, including office duty and flight duty. He stated that he feels the lack of days off during the previous 19 days was a contributing factor to this accident. When asked what would have prevented the accident, the pilot suggested consistency in using the checklist. On two flights earlier in the day he had used a written checklist; on the accident flight he did not.

The pilot was returning a group of skydivers to their home base after a weekend of skydiving. He flew several jump flights, and then stopped early in the afternoon to prepare the airplane for the flight home. The flight was planned into an area of clouds, turbulence, and icing, which the pilot had researched. He delayed the departure until he decided that he could complete the planned flight under visual flight rules (VFR). The accident occurred at night with little illumination of the moon, and the airplane was in an area of layered clouds. A detailed analysis of the weather conditions revealed that the flight probably encountered broken to overcast layers both below and above its flight altitude. The satellite and sounding images suggested that it was possibly in an area of mountain wave conditions, which can enhance icing. The recorded radar data indicated that the pilot was likely maneuvering to go around, above, or below rain showers or clouds while attempting to maintain VFR. The airplane likely entered clouds during the last 3 minutes of flight, and possibly icing and turbulence. It was turning when it departed from controlled flight, and a performance study showed that the angle-of-attack at this point in the flight was increasing rapidly. The study determined that the
departure from controlled flight was consistent with an aerodynamic stall. The unpressurized airplane was flying at over 14,000 feet mean sea level for more than 1 hour during the flight. It reached 15,000 feet just prior to the accident in sequential 360-degree turns while climbing and descending. Supplemental oxygen was not being used. At these altitudes, the pilot would be substantially impaired by hypoxia, but would have virtually no subjective symptoms, and would likely be unaware of his impairment. The pilot had logged over 2,000 hours of total flight time, with nearly 300 hours in this make and model of airplane. He was instrument rated, but had only logged a total of 2 hours of actual instrument flight time. Company policy was to fly under visual flight rules only, and they had not flight-checked the pilot for instrument flight.

While cruising en route in VFR conditions, the aircraft lost power on both engines. The pilot attempted an emergency forced landing at a nearby unpaved State airport, but after encountering a 20 mph tailwind on downwind and a 20 mph headwind on final, the aircraft impacted a tall conifer tree while about one-half mile from the approach end of the runway. The reason for the dual engine power loss was not determined.

During a cross country flight, the pilot was informed by air traffic control that adverse weather was along his route of flight for terrain obscurement in clouds, precipitation, fog or mist. Turbulence was reported below 12,000 feet and occasional moderate rime or mixed icing was reported from the freezing level to 14,000 feet. Further along the route, the pilot reported to another controller that he was at 13,000 feet and descending. The controller inquired if the pilot was aware of the center weather advisory and the reports of severe rime ice in the direction that he was heading. The pilot acknowledged the controller by reporting that he was aware of the weather and that the aircraft was "equipped." The controller continued to inform the pilot of pilot reports from commercial aircraft flight crews of the reports of icing conditions, however, the pilot continued on his routing and again reported that the aircraft was "equipped." During the last transmissions from the pilot, he reported that he was "turning on (de-ice) equipment now." The controller recommended to the pilot to stay clear of the clouds. The pilot responded, "roger." The controller then asked the pilot if he was "going to orbit there for awhile." The pilot responded, "yes," followed by a partially unintelligible transmission of "getting some weather here." The pilot's last transmissions were "Ah, I'm in a little trouble," followed by "Ah, standby 9KM." Radar tracking indicated that the aircraft had been cruising at 16,500 feet before starting a gradual descent. The aircraft descended to 12,700 feet and it began a turn to the right. During this turn, the aircraft's altitude changed rapidly beginning with an increase, followed by a rapid loss of altitude from 8,000 feet per minute descent to 10,600 feet per minute descent before radar contact was lost. The aircraft was found 6 months later in an area of mountainous terrain. On site evidence indicated that the aircraft collided with trees and terrain in a nose low attitude with the majority of the wreckage contained in a large deep crater.

The pilot, who had more than 3,340 hours of pilot-in-command time in the make/model of the accident aircraft, and was very familiar with the destination airport and its ILS approach procedure, departed on a cargo flight in the SA227 turboprop aircraft. The aircraft was dispatched with the primary (NAV 1) ILS receiver having been deferred (out of service) due to unreliable performance the evening before the accident, thus leaving the aircraft with the secondary (NAV 2) ILS receiver for ILS use. The pilot arrived in the destination terminal area and was given vectors to intercept the ILS localizer, and radar data showed the aircraft intercepting and tracking the localizer accurately throughout the approach. Mode C altitude readouts showed the aircraft approaching from below the glideslope at the required intercept altitude of 4,100 feet, passing through and above the glideslope and then initiating a relatively constant descent, the angle of which exceeded the glideslope angle of -3.5 degrees. Weather at the destination airport was 400 foot overcast and the decision height for the ILS/DME runway 21R approach was 270 feet. The aircraft passed through the tops of trees in level flight about 530 feet above the airport elevation and slightly under 3 nautical miles from the runway threshold. The pilot was given a low altitude alert by the tower and acknowledged, reporting that he was descending through 2,800 feet, which was confirmed on the mode C radar readout. At that point the aircraft was well below the ILS glideslope and about 13 seconds from impacting the trees. Post crash examination of information captured from the left and right HSI units and an RMI revealed that the NAV 1 receiver was most likely set on the ILS frequency, and the NAV 2 receiver was most likely set on Spokane VORTAC, a terminal navigation facility located very slightly right of the nose of the aircraft and 14 nautical miles southwest of the destination airport.

The corporate jet airplane experienced a loss of elevator trim control (runaway trim) that resulted in an uncommanded nose-low pitch attitude. The pilot reported that following the loss of elevator trim authority the airplane was extremely difficult to control and the elevator control forces were extremely high. The pilot continued to maneuver the airplane, but eventually ditched it into a nearby marine cove. The runaway trim condition was not immediately recognized by the pilot and he stated that, by that point in the event sequence, the control forces were so great that he had little time to troubleshoot the system and elected to continue on his established heading and ditch the airplane. Pulling the circuit breaker, which is called for by the checklist in the event of a trim runaway, would have arrested the trim movement. Post accident examination and functional testing of the airplane's electric pitch trim printed circuit board (PCB) showed a repeatable fault in the operation of the PCB's K6 relay, resulting in the relay contacts remaining closed. This condition would be representative of the autopilot pitch trim remaining engaged, providing an electrical current to drive continuous nose-down trim to the elevator trim motor. Examination of the airplane's maintenance records showed that the PCB was removed and replaced in conjunction with the
phase inspection prior to the accident. Further examination of the airplane's maintenance records revealed that the replacement PCB was originally installed in an airplane that experienced an "electric trim runaway on the ground." Following the trim runaway, the PCB was removed and shipped to the manufacturer. After receiving the PCB the manufacturer tested the board and no discrepancies were noted. The unit was subsequently approved for return to service and later installed on the accident airplane. The investigation revealed a single-point failure of trim runaway (failed K6 relay) and a latent system design anomaly in the autopilot/trim disconnect switch on the airplane's pitch trim PCB. This design prohibited the disengagement of the electric trim motor during autopilot operation. As a result of the investigation, the FAA issued three airworthiness directives (AD 2003-21-07, AD 2003-23-20, and AD 2004-14-20), and the pitch trim printed circuit board was redesigned and evaluated for compliance with safety requirements via system safety assessment.

The Co-Pilot was the flying pilot with the Captain giving directions throughout the approach phase. The Captain stated that he extended the flaps and the landing gear. When the aircraft touched down, the landing gear was not extended. The Co-Pilot reported that she did look down at the landing gear lever and at "three green lights" on the approach. The CVR was read out which indicated that the Co-Pilot directed the Captain to call inbound. The Captain acknowledged this and stated "fifteen flaps." The Co-Pilot then stated "fifteen flaps, before landing." The Captain did not respond to the Co-Pilot but instead made a radio transmission. The Captain shortly thereafter, stated that he was extending the flaps to 25 degrees. The Captain made another radio transmission to the tower when the Co-Pilot stated "final, sync, ignitions." The Captain responded "ignitions on." Full flaps were then extended. The Captain gave the Co-Pilot continued directions while on the approach for heading, speed and altitude. At approximately 300 feet, the Captain stated, "yaw damper's off, air valves are off, ready to land." The Captain reported that it was obvious that touchdown was on the flaps and keel. The Captain stated that he raised the flaps, shutdown the engines, and confirmed that the landing gear handle was down. During the gear swing test the landing gear cycled several times with no difficulties. All red and green lights illuminated at the proper positions. During the test, it was found that the gear not extended horn did not function with the gear retracted, the flaps fully extended and the power levers at idle. Later a bad set of contacts to the relay was found. When the relay was jumped, the horn sounded. Inspection of the damage to the aircraft revealed that the outer rims of both outer tires displayed scrape marks around the circumference of the rim. The outer surface of the gear door fairings were scraped and the flap hinge fairings was ground down.

The crew had originally planned to practice landings at an airport about 20 minutes away, then stop, refuel the airplane, and subsequently return to the original departure airport. Prior to the flight, the crew discussed fuel endurance, which was calculated to be 2 hours based on the captain's knowledge of the airplane's fuel consumption, and the quantity of fuel indicated on the gauges. The fuel tanks were not dipped. The flight was made at 1,500 feet msl. Upon reaching the practice airport, the crew conducted one full stop landing, then taxied back for takeoff. During takeoff, an engine had a momentary overspeed, and the crew decided to return to the original departure airport without refueling. Approaching the original departure airport, the airplane had to delay landing for about 7 minutes for a manual gear extension. Upon completion, it turned back toward the airport, and was about 6 miles from the runway when fuel pressure for one of the engines dropped. The boost pumps were turned on; however, the engine lost power. A low fuel pressure light then illuminated for another engine. The captain called for the flight engineer to switch fuel feed to another tank, but the flight engineer responded, "we're out of fuel." The remaining engines subsequently lost power, and the captain ditched the airplane into a bay. The time from first takeoff until ditching was 1 hour, 19 minutes. The airplane had flown 39 hours since restoration, and exact fuel capacities, fuel flow calculations and unusable fuel amounts had not been established. A dipping chart had been prepared, with one person in the cockpit and one person with a yardstick putting fuel in a main tank in 25-gallon increments. However, the data had not been verified, and dipping was not considered to be part of the pre-flight inspection.

With a reported ceiling of 500 feet and visibility of 2 miles, the pilot requested and received a Special Visual Flight Rules (VFR) clearance to depart the Bellingham airport. He then took off and called clear of Bellingham's Class D airspace. A witness reported seeing the aircraft flying very low over water near the accident site, appearing to go in and out of clouds, and subsequently seeing it turn toward rising wooded terrain and disappear into the clouds. The aircraft crashed shortly thereafter. Witnesses reported very low ceilings and fog in the accident area at the time. Pieces of the aircraft's left wing and left horizontal stabilizer, along with a felled treetop, were found between the location of the witness's sighting and the main crash site, on or near the crest of a hill about 1/4 mile from the main crash site. These pieces exhibited leading-edge and primary structure damage, and leading-edge-embedded plant material, consistent with the pieces separating from the aircraft upon contact with trees. Wreckage and impact signatures at the main crash site were indicative of an uncontrolled impact with the ground. Investigators found no evidence of any aircraft malfunctions or cargo anomalies occurring prior to the apparent tree strikes.