United States of America

According the commercial pilot and a flight instructor rated check pilot, they were conducting their first long-duration, aerial observation flight in the multiengine airplane, which was recently acquired by the operator. They departed with full fuel tanks, competed the 5-hour aerial observation portion of the flight, and began to return to the destination airport. About 15 miles from the airport, the left engine fuel warning light illuminated. Within a few seconds, the right engine stopped producing power. They attempted to restart the engine and turned the airplane toward an alternate airport that was closer. The pilots then turned on the electric fuel pump, the right engine began surging, and soon after the left engine stopped producing power. They turned both electric fuel pumps to the low setting, both engines continued to surge, and the pilots continued toward the alternate airport. When they were about 3 miles from the airport, both engines lost total power, and they elected to land on a highway. When they were a few feet above the ground, power returned briefly to the left engine, which resulted in the airplane climbing and beginning to roll. The commercial pilot pulled the yoke aft to avoid a highway sign, which resulted in an aerodynamic stall, and subsequent impact with trees and terrain. The airplane sustained substantial damage to the wings and fuselage. Although both pilots reported the fuel gauges indicated 20 gallons of fuel remaining on each side when the engines stopped producing power, the flight instructor noted that there was no fuel in the airplane at the time of the accident. In addition, according to a Federal Aviation Administration inspector who responded to the accident site, both fuel tanks were breached and there was no evidence of fuel spillage.

The student pilot, who was not qualified to operate the airplane, reportedly flew from California to Pennsylvania on a commercial flight the morning of the accident to pick up and fly the accident airplane, which he purchased, to California. The student pilot departed Pennsylvania at 0719 and made several en route stops before arriving at the departure airport at 1949. A witness stated that the airplane’s right engine quit during taxi at the last en route stop and the pilot said he "cut it a little close on fuel." Another witness said that the pilot was “really tired” and planned to fly over the mountains for his return flight. The student pilot was not in communications with air traffic control while en route from the departure airport and did not receive an instrument flight rules clearance to operate the flight in class A airspace as required by Federal Aviation Regulations. The airplane was not equipped with automatic dependent surveillance-broadcast as required for flight in class A airspace. Radar track data indicate the airplane last departed from Fort Collins, Colorado, and maneuvered while climbing to 16,000 ft. The airplane proceeded west/southwest for a little over 40 miles before climbing to about 22,000 ft. The airplane then made several large heading changes and altitude changes between 20,000 ft and 23,000 ft before entering a tight looping turn to the left and losing altitude rapidly before track data was lost. All components of the airplane were distributed along the wreckage path in a manner consistent with a low-angle, high-speed impact with terrain. The airplane was destroyed. A green cylindrical tank consistent in color with an oxygen tank was separated from the airframe and was found along the wreckage path. Portions of pneumatic lines were attached to the tank and exhibited impact damage and separations from impact. Due to accident-related damage, the amount of the tank’s contents prior to the accident are unknown, and the functionality, if any, of the oxygen system is unknown. The reason for the airplane’s impact with terrain could not be determined based on available evidence.

Shortly after takeoff the pilot reported to the air traffic controller that he was losing engine power. The pilot then said he was going to divert to a nearby airport and accepted headings to the airport. The pilot then reported the loss of engine power had stabilized, so he wanted to return to his departure airfield. A few moments later the pilot reported that he was losing engine power again and he needed to go back to his diversion airport. The controller reported that another airport was at the pilot’s 11 o’clock position and about 3 miles. The pilot elected to divert to that airport. The airplane was at 4,500 ft and too close to the airport, so the pilot flew a 360° turn to set up for a left base. During the turn outbound, the engine lost all power, and the pilot was not able to reach the runway. The airplane impacted a field, short of the airport. The airplane’s wings separated in the accident and a small postcrash fire developed. A review of the airplane’s maintenance records revealed maintenance was performed on the day of the accident flight to correct reported difficulty moving the Power Control Lever (PCL) into reverse position. The control cables were inspected from the pilot’s control quadrant to the engine, engine controls, and propeller governor. A static rigging check of the PCL was performed with no anomalies noted. Severe binding was observed on the beta control cable (propeller reversing cable). The cable assembly was removed from the engine, cleaned, reinstalled, and rigged in accordance with manufacturer guidance. During a post-accident examination of the engine and propeller assembly, the beta control cable was found mis-rigged and the propeller blades were found in the feathered position. The beta valve plunger was extended beyond the chamfer face of the propeller governor, consistent with a position that would shut off oil flow from the governor oil pump to the constant speed unit (CSU). A wire could be inserted through both the forward and aft beta control cable clevis inspection holes that function as check points for proper thread engagement. The forward beta control cable clevis adjustment nut was rotated full aft. The swaging ball end on the forward end of the beta control cable was not properly secured between the clevis rod end and the push-pull control terminal and was free to rotate within the assembly. Before takeoff, the beta valve was in an operational position that allowed oil flow to the CSU, resulting in normal propeller control. Vibration due to engine operation and beta valve return spring force most likely caused the improperly secured swaging ball to rotate (i.e. “unthread”) forward on the beta control cable. The resulting lengthening of the reversing cable assembly allowed the beta valve to stroke forward and shut off oil flow to the propeller CSU. Without propeller servo oil flow to maintain propeller control, the propeller faded to the high pitch/feather position due to normal leakage in the transfer bearing. The reported loss of power is consistent with a loss of thrust due to the beta control cable being mis-rigged during the most recent maintenance work.

Air traffic control communications revealed that the pilot requested to take off from the departure runway so that he could perform traffic pattern work and return for a landing on the left adjacent runway. Shortly after takeoff and while departing to the west, the pilot was instructed twice to enter the left traffic pattern, with no response. Radar data showed the airplane departing the runway and remaining on runway centerline heading for the length of the flight. The airplane climbed to about 100 ft above ground level and the airplane’s groundspeed increased to 81 knots soon after departure then decreased to 70 knots before dropping off radar. Witnesses reported seeing the airplane depart the airport at a low climb rate and slow airspeed. Shortly after, the airplane flew out of view and a column of smoke was seen on the horizon. Accident site documentation identified symmetrical propeller strikes on the ground consistent with the airplane impacting the ground in a shallow, nose-up, wings level attitude. Examination of the airframe and both engines did not reveal any evidence of a preaccident mechanical failure or malfunction that would have precluded normal performance to allow for sufficient airspeed and climb rate after takeoff. Both the engines exhibited damage signatures consistent with the engines producing symmetrical power at impact. The pilot’s most recent flight in the accident airplane was 2 months before the accident. The pilot was reported to have problems with understanding the accident airplane’s avionics system; however, it is unknown if he was having these problems during the accident flight. Review of the pilot’s medical history revealed no significant medical concerns or conditions that could pose a hazard to flight.

The pilot was conducting a Part 135 on-demand cargo flight in instrument meteorological conditions. After executing a second missed approach, he informed air traffic control (ATC) of his intentions to divert to an airport located about 36 miles to the southeast. About 7 minutes after executing the second missed approach, the pilot began making unintelligible radio communications that ATC characterized as very garbled and difficult to understand, “almost hypoxic.” ATC then instructed the pilot to utilize oxygen. About 19 minutes after the second missed approach, ATC informed the pilot that the airplane had descended 1,600 ft, not following assigned course vectors or instructions and asked if everything was alright, to which no response was received. After attempting to relay communications through other airplanes in the area, an unintelligible response was received from the accident airplane. ATC then made numerous transmissions to the accident pilot urging him to utilize oxygen and open a window. No further communications were received from the accident airplane. A witness reported that he saw the airplane descend out of a low overcast cloud layer at a high rate of descent. The airplane then abruptly transitioned into a steep climb before re-entering the clouds. A few seconds later, he heard the airplane impact terrain and responded to the accident site. The sudden change in communications from the pilot indicates a possible impairment. When combined with the ATC data, the witness account, and the lack of any mechanical irregularities or malfunctions with the airplane, it is likely the pilot experienced difficulty controlling the airplane due to impairment. While the pilot was at an increased risk for an acute cardiovascular event, the extremely limited available medical evidence leaves no way to quantify that risk and no evidence regarding whether such an event occurred. As a result, whether the pilot was incapacitated by an acute medical event cannot be determined from the available medical information.

The pilot stated that, upon landing, the airplane touched down on the runway centerline with light and variable wind conditions. The pilot recalled that the touchdown felt normal but that, during the landing roll, the airplane began to veer to the right. The pilot added full left rudder, but the airplane continued to veer off the runway surface and encountered large rocks located between the runway and taxiway. A postaccident operational check of the nosewheel steering system revealed no mechanical malfunctions or anomalies that would have precluded normal operation. The left nosewheel tire was not adequately inflated and was worn to the point at which the cord was exposed; the right nosewheel tire was within tolerances. Also, one-third of the rim was absent on the left nosewheel tire outer wheel half. The available evidence precluded a determination of whether the imbalance between the nosewheel tires contributed to the control problem on the runway. It could also not be determined if the left nosewheel tire damage occurred before the touchdown or as a result of the accident sequence.

The pilot reported that, upon reaching the decision altitude on a GPS instrument approach, he saw the runway end identifier lights and continued the approach. Shortly after, the lights disappeared and then reappeared. He continued the approach and landing thinking the airplane was lined up with the runway by using the runway edge lights for reference. Upon touching down about 225 ft left of the runway, the airplane dug into snow and flipped over, which resulted in substantial damage to the wings and tail. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

The pilot departed on an instrument flight rules cross-country flight with three passengers. While enroute at a cruise altitude about 6,000 ft mean sea level (msl), the pilot discussed routing and weather avoidance with the controller. The controller advised the pilot there was a gap in the line of weather showing light precipitation, and that the pilot could pass through it and then proceed on course. The controller assigned the pilot a heading, which the pilot initially acknowledged, but shortly thereafter, he advised the controller that the airplane was pointed directly at a convective cell. The controller explained that the heading would keep the pilot out of the heavy precipitation and that he would then turn the airplane through an area of light precipitation. The pilot responded, saying that the area seemed to be closing in fast, the controller acknowledged and advised the pilot if he did not want to accept that routing, he could be rerouted. The pilot elected to turn toward a gap that he saw and felt he could fly straight through it. The controller acknowledged and advised the pilot that course would take him through moderate precipitation starting in about one mile extending for about four miles; the pilot acknowledged. Radar information indicated that the airplane entered an area of heavy to very heavy precipitation, likely a rain shower updraft, while in instrument meteorological conditions, then entered a right, descending spiral and broke up in flight. Examination of the wreckage revealed no evidence of a preaccident malfunction or failure that would have prevented normal operation. The airplane was equipped with the capability to display weather radar "mosaic" imagery created from Next Generation Radar (NEXRAD) data and it is likely that the pilot was using this information to navigate around precipitation when the airplane encountered a rain shower updraft with likely severe turbulence. Due to latencies inherent in processes used to detect and deliver the NEXRAD data from the ground site, as well as the frequency of the mosaic-creation process used by the service provider, NEXRAD data can age significantly by the time the mosaic image is created. The pilot elected to navigate the hazardous weather along his route of flight based on the data displayed to him instead of the routing suggested by the controller, which resulted in the penetration of a rain shower updraft, a loss of airplane control, and a subsequent inflight breakup.

The pilot reported that he and the copilot were conducting an instrument approach to the runway in a business jet. He noted that the weather conditions included fog and mist. After touching down about 1,500 ft down the 7,300-ft-long runway, he engaged the thrust reversers and applied the brakes gradually because the runway was "slippery." As the airplane approached the end of the runway, he applied full braking, but the airplane departed the end of the runway and impacted a ditch, which resulted in the forward landing gear breaking and the airplane nosing down. The copilot corroborated the pilot's statement. The fuselage was substantially damaged. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

The pilot was receiving a checkride from a designated pilot examiner for his single-pilot type rating in a turbine airplane. After a series of maneuvers, emergencies, and landings, the examiner asked the pilot to complete a no-flap landing. The pilot reported that he performed the Before Landing checklist with no flaps and believed that he had put the gear down. During touchdown, the pilot felt a "thump" and thought a tire had blown; however, he saw that the landing gear handle was in the "up" position, and he noted that the landing gear warning horn did not sound because he had performed a no-flaps landing. The examiner confirmed that the landing gear handle was in the "up" position. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. A Federal Aviation Administration inspector who examined the airplane reported that the landing gear handle was in the "up" position and that the fuselage had sustained substantial damage. The landing gear was lowered and locked into place without issue after the airplane was lifted from the runway.