Private

The pilot of the Part 91 business flight filed an instrument-flight-rules (IFR) flight plan with the destination and alternate airports, both of which were below weather minimums. The pilot and
copilot departed from the departure airport in weather minimums that were below the approach minimums for the departure airport. While en route, the destination airport's automated observing system continued to report weather below approach minimums, but the flight crew continued the flight. The flight crew then requested and were cleared for the instrument landing system (ILS) 31 approach and while on that approach were issued visibilities of 1,800 feet runway visual range after changing to tower frequency. During landing, the copilot told the pilot that he was not lined up with the runway. The pilot reportedly said, "those are edge lights," and then realized that he was not properly lined up with the runway. The airplane then touched down beyond a normal touchdown point, about 2,800 feet down the runway, and off the left side of the runway surface. The airplane veered to the left, collapsing the nose landing gear. Both flight crewmembers had previous experience in Part 135 operations, which have more stringent weather requirements than operations conducted under Part 91. Under Part 135, IFR flights to an airport cannot be conducted and an approach cannot begin unless weather minimums are above approach minimums. The accident flight's departure in weather below approach minimums would have precluded a return to the airport had an emergency been encountered by the flight crew, leaving few options and little time to reach a takeoff alternate airport. The company's flight procedures allow for a takeoff to be performed as long as there is a takeoff alternate airport within one hour at normal cruise speed and a minimum takeoff visibility that was based upon the pilot being able to maintain runway alignment during takeoff. The company's procedures did not allow flight crew to depart to an airport that was below minimums but did allow for the flight crew, at their discretion, to
perform a "look-see" approach to approach minimums if the weather was below minimums. The allowance of a "look see" approach essentially negates the procedural risk mitigation afforded by requiring approaches to be conducted only when weather was above approach minimums.

The pilot was on a cross-country flight near mountainous terrain when he encountered clouds along the flight path. A comparison of recorded radar data and weather reports in the local area indicated that the pilot was maneuvering near the cloud bases in an area with low visibility and ceilings. Based on the erratic and circling flight path, it is likely that the pilot was having difficulty determining his location and desired flight track when the airplane collided with terrain. Post accident examination of the airframe and engine revealed no mechanical failures or malfunctions that would have precluded normal operation.

On his first Instrument Landing System (ILS) approach, the pilot initially flew through the localizer course. The pilot then reestablished the airplane on the final approach course, but the airplane’s altitude at the decision height was about 500 feet too high. He executed a missed approach and received radar vectors for another approach. The airplane was flying inbound on the second ILS approach when a witness reported that he saw the airplane about 150 feet above the ground in about a 60-degree nose-low attitude with about an 80-degree right bank angle. The initial ground impact point was about 2,150 feet west of the runway threshold and about 720 feet north (left) of the extended centerline. The cloud tops were about 3,000 feet with light rime or mixed icing. The flap jack screws and flap indicator were found in the 5-degree flap position. The inspection of the airplane revealed no preimpact anomalies to the airframe, engines, or propellers. A radar study performed on the flight indicated that the calibrated airspeed was about 130 knots on the final approach, but subsequently decreased to about 95–100 knots during the 20-second period prior to loss of radar contact. According to the airplane’s flight manual, the wings-level power-off stall speed at the accident aircraft’s weight is about 91 knots. The ILS approach flight profile indicates that 20 degrees of flaps should be used at the glide slope intercept while maintaining 120 knots minimum airspeed. At least 20 degrees of flaps should be maintained until touchdown. The “No Flap” or “5 Degrees Flap Landing” flight profile indicates that the NO FLAP Vref airspeed is 115 knots calibrated airspeed minimum.

The multiengine airplane was at an altitude of 6,000 feet when it experienced a catastrophic right engine failure, approximately 15 minutes after takeoff. The pilot elected to return to his departure airport, which was 30 miles away, instead of diverting to a suitable airport that was located about 10 miles away. The pilot reported that he was not able to maintain altitude and the airplane descended until it struck trees and impacted the ground, approximately 3 miles from the departure airport. The majority of the wreckage was consumed by fire. A 5 1/2 by 6-inch hole was observed in the top right portion of the crankcase. Examination of the right engine revealed that the No. 2 cylinder separated from the crankcase in flight. Two No. 2 cylinder studs were found to have fatigue fractures consistent with insufficient preload on their respective bolts. In addition, a fatigue fracture was observed on a portion of the right side of the crankcase, mostly perpendicular to the threaded bore of the cylinder stud. The rear top 3/8-inch and the front top 1/2-inch cylinder hold-down studs for the No. 2 cylinder exceeded the manufacturer's specified length from the case deck by .085 and .111 inches, respectively. The airplane had been operated for about 50 hours since its most recent annual inspection, which was performed about 8 months prior the accident. The right engine had been operated for about 1,425 hours since it was overhauled, and about 455 hours since the No. 2 cylinder was removed for the replacement of six cylinder studs. It was not clear why the pilot was unable to maintain altitude after the right engine failure; however, the airplane was easily capable of reaching an alternate airport had the pilot elected not to return to his departure airport.

During the flight, the instrument-rated private pilot was monitoring the weather at his intended destination. He noted the weather and runway conditions and decided to conduct a global-positioning-system instrument approach to a known closed runway with the intention of circling to a different runway. As the airplane neared the missed approach point, the pilot established visual contact with the airport's runway environment and canceled his instrument flight rules clearance. As he entered the left downwind leg of the traffic pattern for his intended runway, the pilot noticed that the first part of the runway was covered in fog and that the visibility was 0.75 of a mile with light snow. With at least 5,000 feet of clear runway, he opted to land just beyond the fog. Prior to touchdown, the pilot concluded that there was not enough runway length left to make a landing and performed a go-around by applying power, pitching up, and retracting the landing gear. During the go-around, the pilot focused outside the airplane cockpit but had no horizon reference in the dark night conditions. He heard the stall warning and realized that the aircraft was not climbing. The pilot pitched the nose down and observed only snow and trees ahead. Not being able to climb over the trees, the airplane subsequently impacted trees and terrain, coming to rest upright in a wooded, snow-covered field. The pilot stated that there were no anomalies with the engine or airframe that would have precluded normal operation of the airplane.

The pilot was established on the localizer portion of the instrument landing system approach outside the final approach fix in visual meteorological conditions above clouds. He was then given vectors away from the localizer course by an air traffic controller. The vectors were close together and included a left 90-degree turn, a descent, and a 180-degree right turn back toward the localizer course. During the right turn and descent, the airplane continued turning with increasing bank and subsequently impacted the ground. According to a pilot weather report and flight path data the pilot entered clouds as he was starting the right turn toward the localizer. The combination of descending turns while entering instrument conditions were conducive to spatial disorientation. Further, the heading changes issued by the air traffic controller were rapid, of large magnitude, and, in combination with a descent clearance, likely contributed to the pilot’s disorientation. Diphenhydramine, a drug that may impair mental and/or physical abilities, was found in the pilot’s toxicological test results. While the exact effect of the drug at the time of the accident could not be determined, it may have contributed to the development of spatial disorientation.

The pilot obtained three weather briefings before departure. At that time, the current weather along the route of flight showed significant convective activity and a moving squall line, and the forecast predicted significant thunderstorm activity along the planned route of flight. The pilot was concerned about the weather and mentioned that he would be looking for "holes" in the weather to maneuver around via the use of his on-board weather radar. He decided to fly a route further south to avoid the severe weather. Radar data indicates that, after departure, the pilot flew a southerly course that was west of the severe weather before he asked air traffic control for a 150-degree heading that would direct him toward a "hole" in the weather. A controller, who said he also saw a "hole" in the weather, told the pilot to fly a 120-degree heading and proceed direct to a fix along his route of flight. The airplane flew into a line of very heavy to intense thunderstorms during cruise flight at 25,000 feet before the airplane began to lose altitude and reverse course. The airplane then entered a rapid descent, broke up in flight, and subsequently impacted terrain. Review of recorded precipitation data showed that there was substantial information available to the controller about moderate to extreme weather along the aircraft’s route of flight. While the controller stated that he saw a hole or clear area ahead of the aircraft, this is contradicted by both the recorded data and the statement of a second controller working the D-position at the time of the accident. The first controller did not advise the pilot of the severe weather that was along this new course heading and the pilot entered severe weather and began to lose altitude. The controller queried the pilot about his altitude loss and the pilot mentioned that they had gotten into some "pretty good turbulence." This was the last communication from the pilot before the airplane disappeared from radar. Review of recorded precipitation data showed that there was substantial information available to the controller about moderate to extreme
weather along the aircraft’s route of flight. The controller did not provide advisories to the pilot regarding the adverse weather's immediate safety hazard to the accident flight as required by Federal Aviation Administration Order 7110.65. Examination of the recovered sections of flight control surfaces revealed that all of the fractures examined exhibited signs consistent with overstress failure. There was no evidence of preexisting cracking on any of the fracture surfaces examined and no preaccident anomalies were noted with the engines.

The pilot fueled the airplane prior to departure and flew uneventfully for approximately 30 minutes. The airplane then descended to 2,000 feet on approach to the destination airport, during night visual meteorological conditions. About 30 seconds after being cleared for a visual approach, the pilot declared an emergency to air traffic control and requested assistance to the nearest airport. The controller provided a vector to divert and distance to the nearest suitable airport. The pilot subsequently reported "engine out, engine out" and the airplane impacted wooded terrain about 4 miles northeast of runway 22 at the alternate airport. A post crash fire consumed a majority of the wreckage. Examination of the wreckage, including teardown examination of the engine, did not reveal any preimpact mechanical malfunctions; however, the fuel system and ignition system were consumed by post crash fire and could not be tested.

The pilot added fuel to the multi-engine airplane prior to departure. While en route to the destination airport, the pilot noted that the fuel gauges indicated that the right main-tank appeared to be almost empty and the left tank appeared half full. The pilot initiated the crossfeed procedure in an effort to supply fuel to both engines from the left main tank. Shortly after beginning the crossfeed procedure, both engines experienced a total loss of power. The pilot notified air traffic control (ATC) and selected a field to perform a forced landing. Prior to touchdown, the right engine produced a surge of power and, in response, the airplane rolled to the left. The surge abruptly ended and the pilot continued the forced landing by lowering landing gear and extending the flaps. The airplane impacted the ground, coming to rest in an open field. A postimpact examination did not reveal any anomalies with the airframe or engine that would have precluded normal operation. Although both fuel tanks were ruptured, the accident scene did not contain a large amount of residual fuel. A small fuel slick was found on the surface of a nearby pond; however, the grass area underneath both wings did not contain dead grass; this would have been expected if there was more than a negligible amount of fuel in the tanks at time of impact.

The twin engine aircraft departed Valle de la Pascua Airport on a private flight to Charallave. While approaching Charallave-Óscar Machado Zuloaga Airport, the crew encountered limited visibility due to low clouds when the aircraft struck the slope of a mountain located near Quiripital, about 15 km southeast of Charallave Airport. The wreckage was found the following day. The aircraft disintegrated on impact and all three occupants were killed.