Portland

The crew was conducting an on-demand charter flight with eight passengers onboard. As the flight crew taxied the airplane to the departure runway, the copilot called air traffic control using his mobile phone to obtain the departure clearance and release. According to the pilot, while continuing to taxi, he stopped the airplane short of the runway where he performed a rudder bias check (the last item in the taxi checklist) and applied the parking brake without verbalizing the parking brake or rudder bias actions because the copilot was on the phone. After the pilot lined up on the runway and shortly before takeoff, the flight crew discussed and corrected a NO TAKEOFF annunciation for an unsafe trim setting. After the copilot confirmed takeoff power was set, he stated that the airplane was barely moving then said that something was not right, to which the pilot replied the airplane was rolling and to call the airspeeds. About 16 seconds later, the pilot indicated that the airplane was using more runway than he expected then made callouts for takeoff-decision speed and rotation speed. The pilot stated that he pulled the yoke back twice, but the airplane did not lift off. Shortly after, the pilot applied full thrust reversers and maximum braking, then the airplane exited the departure end of the runway, impacted a ditch, and came to rest 1,990 ft beyond the departure end of the runway. The airplane was destroyed by a postcrash fire, and the crew and passengers were not injured.

The private pilot and passenger departed on the 875-nautical-mile cross-country flight and leveled off at a cruise altitude of 24,000 feet mean seal level, which, based on the radar data, was accomplished with the use of the autopilot. About 1 hour 40 minutes after departure, the pilot contacted air traffic control personnel to request that he would “like to leave frequency for a couple of minutes.” No further radio transmissions were made. About 20 seconds after the last transmission, the airplane banked to the right, continued in a spiral while rapidly descending, and subsequently broke apart. At no time during the flight did the pilot indicate that he was experiencing difficulty or request assistance. Just prior to departing from the flight path, the pilot made an entry of the engine parameters in a flight log, which appeared to be consistent with his other entries indicating the airplane was not experiencing any difficulties. Portions of the wings, along with the horizontal stabilizers and elevators, separated during the breakup sequence. Analysis of the fracture surfaces, along with the debris field distribution and radar data, revealed that the rapid descent resulted in an exceedance of the design stress limits of the airplane and led to an in-flight structural failure. The airplane sustained extensive damage after ground impact, and examination of the engine components and surviving primary airframe components did not reveal any mechanical malfunctions or failures that would have precluded normal operation. The airplane was flying on a flight path that the pilot was familiar with over largely unpopulated hilly terrain at the time of the upset. The clouds were well below his cruising altitude, giving the pilot reliable external visual cues should the airplane have experienced a failure of either the flight instruments or autopilot. Further, no turbulence was reported in the area. The airplane was equipped with a supplemental oxygen system, which the pilot likely had his mask plugged into and available in the unstowed position behind his seat; the passenger’s mask was stowed under her seat. The airplane’s autopilot could be disengaged by the pilot by depressing the appropriate mode switch, pushing the autopilot disengage switch on the control wheel, or turning off the autopilot switch on the control head. All autopilot servos were also equipped with a clutch mechanism that allowed the servo to be manually overridden by the pilot at any time. It is likely that the reason the pilot requested to “leave the frequency” was to leave his seat and attend to something in the airplane. While leaving his seat, it is plausible he inadvertently disconnected the autopilot and was unable to recover by the time he realized the deviation had occurred.

The multi-engine airplane was being repositioned to its base airport, and the pilot had requested to change the destination, but gave no reason for the destination change. Radar data indicated that the airplane entered the left downwind leg of the traffic pattern, flew at pattern attitude, and then performed a right approximate 250-degree turn to enter the final leg of the approach. During the final leg of the approach, the airplane crashed short of the runway into a house located in a residential neighborhood near the airport. According to the airplane's pilot operating handbook, the minimum multi-engine approach speed was 95 knots indicated airspeed (KIAS), and the minimum controllable airspeed was 82 KIAS. According to radar data, the airplane's ground speed was about 69 knots with the probability of a direct crosswind. Post accident examination of the propellers indicated that both propellers were turning at a low power setting at impact. During a controlled test run of the right engine, a partial power loss was noted. After examination of the throttle and control assembly, two o-rings within the assembly were found to be damaged. The o-rings were replaced with comparable o-rings and the assembly was reinstalled. During the subsequent test run, the engine operated smoothly with no noted anomalies. Examination of the o-rings revealed that the damage was consistent with the o-rings being pinched between the corner of the top o-ring groove and the fuel inlet surface during installation. It is probable that the right engine had a partial loss of engine power while on final approach to the runway due to the damaged o-ring and that the pilot retarded the engine power to prevent the airplane from rolling to the right. The investigation found no mechanical malfunction of the left engine that would have prevented the airplane from maintaining the published airspeed.

The pilot and passenger departed on a night IFR flight. Weather en route was a mixture of instrument and visual meteorological conditions. When the airplane was 17 miles southwest of its destination, the pilot was cleared for an instrument approach. At 9 miles, the pilot reported the airport in sight, and canceled his IFR clearance. The airplane continued to descend towards the airport on a modified left base until radar contact was lost at 3,300 feet msl. The pilot was in radio contact with his wife just prior to the accident. He advised her that he was on base for runway 32. Neither the pilot's wife, nor ATC received a distress call from the pilot. The airplane was located the next morning about 100 feet below the top of a mountain. The accident site was 7.9 miles from the airport, and approximately 1,200 feet above the airport elevation. Ground based weather radar recorded light snow showers, in the general vicinity of the accident site about the time of the accident, and satellite imagery showed that the airplane was operating under a solid overcast. A level path was cut through the trees that preceded the main wreckage. Examination of both engines and the airframe revealed no pre impact failures or malfunctions.

While in cruise flight, at 6,000 feet, the left engine lost power. The pilot attempted a restart of the engine, but only about one-half rotation of the left engine propeller was observed, and the engine was secured. The pilot stated that he was unable to maintain altitude and initiated a decent. He requested and was cleared for an instrument approach at an airport where the weather conditions were, 1/4 statute mile of visibility, fog, and a vertical visibility of 100 feet. On the approach, at the minimum descent altitude, the pilot executed a missed approach. As the airplane climbed, the pilot reported to the controller that the 'best altitude [he] could get was 2,200 feet.' A second approach was initiated to the reciprocal runway. While on the second approach, the pilot 'was going to fly the aircraft right to the runway, and told the controller so.' He put the gear down, reduced power, and decided there was 'no hope for a go-around.' He then 'flew down past the decision height,' and about 70-80 feet above the ground, 'added a little power to smooth the landing.' The pilot also stated, 'The last thing I remember was the aircraft nose contacting the runway.' A passenger stated that once the pilot could not see the runway, [the pilot] 'applied power, pitched the nose up,' and attempted a 'go-around' similar to the one that was executed on the first approach. Disassembly of the left engine revealed that the crankshaft was fatigue fractured between connecting rod journal number 2 and main journal number 2. Review of the pilot's operating handbook revealed that the single engine service ceiling, at a weight of 4,800 pounds, was 11,700 feet. The average single engine rate of climb, at a pressure altitude of 6,000 feet, was 295 feet per minute. The average single engine rate of climb, at a pressure altitude of 1,625 feet, was 314 feet per minute. Review of the ILS approach plate for Runway 34 revealed that the decision height was 200 feet above the ground.

The Beech 1900C cargo aircraft was loaded with more than 4,962 pounds of cargo during an approximate 20 minute period. No scale was available at the aircraft, forcing loaders to rely on tallying either waybill weights or estimates of total cargo weight and center of gravity (CG) during the brief loading period. Additionally, a strike had shut down a major cargo competitor at the time with substantial cargo overflow to the operator. Post-crash examination determined the cargo load was 656 pounds greater than that documented on the pilot's load manifest, and the CG was between 6.8 and 11.3 inches aft of the aft limit. The airplane behaved normally, according to the pilot, until he initiated full flaps for landing approaching the threshold of runway 34L at the Seattle-Tacoma International airport. At this time, the aircraft's airspeed began to decay rapidly and a high sink rate developed as the aircraft entered into a stall/mush condition. The aircraft then landed hard, overloading the nose and left-main landing gear which collapsed. A post-impact fuel system leak during the ground slide led to a post-crash fire.

Based upon digital flight data recorded (DFDR) information, the mishap aircraft departed Portland IAP at 1720 PST on 22 Nov 96 on an instrument flight rules (IFR) flight en route to North Island Naval Air Station. The purpose of the sortie was to conduct an overwater navigation evaluation. King 56 began the sortie with a normal takeoff, departure and climbout. One hour and 24 minutes after takeoff in level flight at FL 220 the mishap sequence began with the engineer commenting on a torque flux on the number 1 engine. Nothing on the cockpit voice recorder (CVR), the DFDR, or the survivor’s testimony suggested any unusual events prior to the engineer’s comment. Over the next three minutes, the operations of all four engines became unstable and eventually failed. Crew actions during these critical three minutes are known only by verbal comments on the CVR and the survivor’s testimony. The following discusses what we know of those actions. The engineer called for n°1 propeller to be placed in mechanical governing. This would normally remove electrical inputs to the propeller through the synchrophaser. The pilot then called for all four propellers to be placed in mechanical governing. This action was consistent with treating this emergency as a four-engine rollback. There is no indication on the DFDR or the CVR as to whether or not the crew selected mechanical governing on any of the remaining three propellers. At the same time the crew was analyzing the emergency, they also declared an in-flight emergency with Oakland ARTCC and turned the mission aircraft east to proceed toward Kingsley Field, Klamath Falls, OR, approximately 230 miles away and approximately 80 miles from the coast. The Radio Operator radioed the USCG Humboldt Bay Station and notified them of the in-flight emergency. During the turn toward the shore the number 3 and number 4 engines once briefly recovered most of their torque. These increases are recorded by the flight data recorder. When the RPM on number 3 (the aircraft’s last functioning engine) finally decreased below 94% RPM the last generator producing electrical power dropped off line due to low frequencies. As a result, at 1846 Pacific Standard Time all electrical power was lost. After a brief period, power was restored to the equipment powered by the battery bus. From this point on, the aircraft glided to the attempted ditching. There is no record of that portion of the flight, except the survivor’s testimony.The outboard wing sections and all four engines separated from the center wing section that in turn separated from the fuselage. Subsequently, the engines and fuselage went straight to the ocean floor at a depth of approximately 5500 feet. The outer wing and the center wing sections floated on the surface for several days and sank more than 50 nm from the impact location. The radio navigator was rescued while 10 other crew members were killed.

The pilot was completing the first leg of an IFR flight in a multi-engine airplane. As the airplane was established on final approach, about 5 miles from the airport, the pilot encountered visual meteorological conditions and canceled his IFR flight plan. Moments later, the right engine began to sputter and then lost power. The pilot said that he switched the fuel selector valves to various positions and positioned the fuel boost pump to high-flow; however, during this time, the left engine also lost power. The pilot attempted to start both engines, but without success. During a forced landing, the airplane struck a pole, then crashed into a condominium. A fire erupted, but all 4 occupants survived the accident. Two occupants in the condominium received minor injuries. The pilot believed that he had moved the fuel selector valves to the auxiliary position for about 1 hour during flight; however, the passengers did not see him move the fuel selectors until after the engine(s) lost power. The right fuel selector handle was found between the right main tank and off positions. The left fuel selector was destroyed by post-impact fire.

The pilot tried to activate the radio-controlled runway boundary lights about 10 miles away, and also while he was in the traffic pattern, but he was unsuccessful. He continued his descent to approximately 500 feet above the ground using the vasi (visual approach slope indicator) lights. The pilot stated that he had the airport in sight and' felt well enough in sight to complete landing.' The airplane touched down in approximately 18 inches of snow 60 feet off the right side of the runway. The pilot reported that there was no mechanical malfunction. He said as he got closer to the ground he realized it was snow-mobile tracks and not the runway. He tried to go-around but the airplane impacted the ground collapsing the nose gear.

Witnesses reported seeing the airplane flying in a normal cruise attitude when it rolled inverted and the nose dropped near vertical to the terrain. The airplane descended in a near vertical dive. The nose of the airplane started to come up horizontal to the terrain when it struck a 75-ft tree. During the post crash investigation, no evidence of a mechanical failure or malfunction was found. Both occupants were killed.