Landing (descent or approach)

Witnesses first observed the aircraft on final approach for landing, with the engine(s) making a backfiring sound. While the aircraft was on short final, another aircraft pulled onto the runway and initiated its takeoff roll. The accident aircraft was observed to initiate a go-around, but did not appear to be gaining altitude and was at what the witnesses thought was a slow airspeed. About mid-field, the accident aircraft made an approximate 45 degree turn from runway heading. Within 1/4 mile from the runway, the aircraft lost altitude. The witness stated that the aircraft was about 80 feet agl when the aircraft stalled, rolled inverted (left wing down) and collided with the flat open terrain in a nose low attitude. A post-crash fire subsequently consumed the wreckage. During the post-crash inspection of the engines, it was found that both engines displayed signs of operating at a lean mixture setting. The left engine pistons and spark plugs displayed a more serious lean condition than the right side and displayed the early signs of detonation on the piston heads. No other mechanical failure or malfunction was noted to either the engines or airframe.

The airplane lost engine power during descent. The 1,127-hour pilot elected to perform emergency engine out procedures and prepared for an emergency landing. After impact, the pilot observed the right engine nacelle engulfed in flames, which then spread to the fuselage. Review of the engine logbook revealed the engine was being operated in excess of 1,000 hours of the manufacturer's recommended time between overhauls of 3,600 hours. The airplane received post-impact fire damage. Further examination of the engine revealed severe fire damage, but no mechanical deficiencies.

The twin-engine airplane was on the base leg to final turn, about 1-1 1/2 miles from the approach end of the runway when the left engine lost power. Instantly after, the right engine lost power and the pilot feathered both engines. The airplane then impacted a 70-foot high tree and collided with the ground about 1,000 feet short of the runway. The 700-hour pilot reported that he activated the electric fuel boost pumps and switched the fuel selectors from the auxiliary fuel tank positions to the main fuel tank positions, about 17 miles from the airport. He recalled that the fuel gauges indicated approximately 70 gallons of fuel in the main tank and about 10-15 gallons of fuel in the auxiliary tanks. The original installed fuel system was configured with a center tank and two outboard tanks. The center tank was composed of five, interconnected rubber cells, having a total capacity of 150 to 159 US gallons. Each outboard fuel tank was composed of two fuel cells with a combined capacity of 33.5 gallons. The total of the two outboard fuel tanks (four cells) was 67 gallons, providing a total usable capacity of 233 gallons. Each engine had its own fuel shutoff switch. Rotating a switch to the RIGHT OUTBOARD or LEFT OUTBOARD position allows fuel from the outboard tanks to flow to the respective engine and shuts off fuel from the center tank. Rotating a fuel shutoff switch to the CENTER position allows fuel to flow from the center tank to the respective engine, and shuts off flow from the respective outboard tank. Rotating the switch to the OFF position shuts off all fuel flow to the respective engine. There was no cross-feed configuration of the switches. Documentation was found in the historical records that indicated extended range fuel system modifications, however, the information was incomplete. After review of all available records and examination of the wreckage, it was determined that the fuel system configuration/capacity of the airplane at the time of the accident was: 156 gallons for the center tank system; 67 gallons for the outboard wing tanks; and a set of auxiliary tanks capable of holding 21 gallons (records of installation unknown). The total usable fuel capacity was estimated at 244 gallons. Cockpit fuel selector positions were: LEFT Fuel Shut Off Valve Selector-LEFT HAND OUTBOARD; LEFT Fuel Boost Pump-OFF; LEFT Engine Primer-OFF; LEFT Ignition Switch-RIGHT; RIGHT Fuel Shut Off Valve Selector-RIGHT HAND OUTBOARD; RIGHT Fuel Boost Pump-ON; RIGHT Engine Primer-OFF; RIGHT Ignition Switch-BOTH. Airframe fuel shutoff valves were found in the following positions (Each valve position corresponded to the cockpit selectors): Right Wing Auxiliary-OPEN; Right Wing Main-CLOSED; Left Wing Auxiliary-OPEN; Left Wing Main-CLOSED. A total of 37.5 gallons of usable fuel was drained from the uncompromised tanks (unknown amount had leaked at the accident site). Excerpts from the " Normal Procedures" section of the flight manual regarding fuel selector positions for take off and landing: "CAUTION; Burn center tank fuel first, when 100 gallons is shown on center tank gauge, switch to outboard tanks. Do not allow engine to be starved of fuel when outboard tanks run dry. Select center tanks at first indication of fuel pressure loss. Fuel boost pumps must be on when switching tanks." The "BEFORE LANDING CHECK" procedures in the aircraft flight manual state that the Fuel Selector Valves must be in the "CENTER TANK" position before the approach. The manufacturer stated that the simultaneous loss of power of both engines was likely a result of the outboard fuel tanks unporting. No mechanical anomalies were found during examination of the engines or airframe, and usable fuel was available in the center tank at the time of the accident.

The fire tanker airplane was on a cross-country positioning flight and collided with mountainous terrain while maneuvering in a canyon near the destination airport. Witnesses who held pilot certificates were on a mountain top at 7,900 feet and saw a cloud layer as far to the south as they could see. They used visual cues to estimate that the cloud tops were around 5,000 feet mean sea level (msl). They noted that the clouds did not extend all the way up into the mountain canyons; the clouds broke up near the head of some canyons. When they first saw the airplane, they assumed that it came from above the clouds. It was proceeding north up a canyon near the edge of clouds, which were breaking up. They were definitely looking down at the airplane the whole time. They saw the airplane make a 180-degree turn that was steeper than a standard rate turn. The wings leveled and the airplane went through one cloud, reappeared briefly, and then entered the cloud layer. It appeared to be descending when they last saw it. About 2 minutes later, they saw the top of the cloud layer bulge and turn a darker color. The bulge began to subside and they observed several smaller bulges appear. They notified local authorities that they thought a plane was down. Searchers discovered the wreckage at that location and reported that the wreckage and surrounding vegetation were on fire. The initial responders reported that the area was cloudy and the visibility was low. Examination of the ground scars and wreckage debris path disclosed that the airplane collided with the canyon walls in controlled flight on a westerly heading of 260 degrees at an elevation of 3,400 feet msl. The operator had an Automated Flight Following (AFF) system installed on the airplane. It recorded the airplane's location every 2 minutes using a GPS. The data indicated that the airplane departed Prescott and flew direct to the Twentynine Palms VORTAC (very high frequency omnidirectional radio range, tactical air navigation). The flight changed course slightly to 260 degrees, which took it to the northeast corner of the wilderness area where the accident occurred. At 1102:57, the data indicated that the airplane was at 11,135 feet msl at 204 knots. The airplane then made three left descending 360-degree turns. The third turn began at 6,010 feet msl. At 1116:57, the last recorded data point indicated that the airplane was at an altitude of 3,809 feet heading 256 degrees at a speed of 128 knots.

The PA-31-310, registration C-FARL, serial number 31306, operated by Les Ailes de Gaspé Inc., with one pilot and two passengers on board, was on a visual flight rules flight from Îles-de-la-Madeleine, Quebec to Gaspé, Quebec. While en route to Gaspé, the pilot was informed about weather conditions at his destination, which were a ceiling at 500 feet and visibility of ¾ mile in fog. The pilot requested clearance for an instrument approach, which he received at approximately 1857 eastern daylight time. A few seconds later the pilot switched on the aerodrome lights with his microphone button. That was the last radio transmission received from the aircraft. When the aircraft did not arrive at its destination, emergency procedures were initiated to find it. The wreckage was found the next day at 1028 eastern daylight time on a hilltop 1.2 nautical miles (nm) north-east of the airport. The aircraft was destroyed, but did not catch fire. The three occupants were fatally injured.

According to the pilot, during climb-out from runway 09 at an altitude of approximately 500 feet the right engine warning red magnetic chip detector light illuminated. The pilot decided to shut down the right engine and return to the airport. Shortly after making that decision the left engine began to lose power. The airplane was unable to maintain altitude, and the pilot prepared to make an off-airport emergency landing in a field. The airplane collided with the trees as the pilot maneuvered for the emergency landing. Examination of the airframe, and flight controls revealed no anomalies. Examination of the left and right engine revealed no mechanical anomalies. Examination of cockpit fuel selector controls revealed that the left engine fuel selector handle was in the off position and the right engine fuel selector handle was set in the left tank position. During the in-flight engine secure procedures the pilot is required to place the inoperative engine fuel selector in the off position.

Upon landing at Wau Airport, the left main gear collapsed. The aircraft veered off runway to the left and came to rest. All five crew members escaped uninjured while the aircraft was damaged beyond repair.

The pilot was conducting an instrument landing system approach during night instrument meteorological conditions. The airplane was observed to descend toward the runway threshold to an altitude consistent with the approach decision height. A witness reported that he heard the airplane overhead, and assumed that the pilot had performed a missed approach. He described the engine noise as "cruise power" and did not hear any unusual sounds. Shortly thereafter, he received a call from airport operations stating that an airplane had crashed. The airplane impacted the ground about 1/4 mile to the left of the runway centerline, about 3,500 feet beyond the approach end of the runway. Examination of the airplane did not reveal any pre-impact mechanical malfunctions. A weather observation taken around the time of the accident, included a visibility 1/2 statue mile in fog, and an indefinite ceiling at 100 feet. The witness described the weather at the time of the accident as thick fog, and "pitch black."

According to the pilot, prior to takeoff, he had the airplane fueled with 20 gallons of fuel in each wing for the short cross-country flight. After takeoff the airplane climbed to an altitude of 9500 feet. During the downwind to the arrival airport the right engine lost power. Shortly after the left engine lost power, the pilot made an emergency off-airport landing. Examination of the fuel system revealed that the fuel tanks were not beached, and there was a small amount of residual fuel in the fuel tanks. The exact amount of fuel onboard the airplane at the time of the departure was not determined.

The purpose of the flight was for the instructor-pilot to prepare the first and second pilots for their FAA Part 135 competency and proficiency checks scheduled to be conducted in the accident airplane the following week, with operator proving tests to follow shortly thereafter. The first pilot obtained a computer science corporation (CSC) direct user access terminal service (DUATS) weather briefing and filed an instrument flight rules (IFR) flight plan. The instructor-pilot was listed as the pilot-in-command. The airplane took off and proceeded to its designated practice area. According to the cockpit voice recorder (CVR), the pilots practiced various maneuvers under the direction of the instructor-pilot, including steep turns and approaches to stalls. Then the first pilot was asked the to demonstrate an approach-to-landing stall. The first pilot asked the instructor-pilot if he had "ever done stalls in the airplane?" The instructor-pilot replied, "It's been awhile." The first pilot remarked, "This is the first time I've probably done stalls in a jet. Nah, I take that back, I've done them in a (Lear)." The instructor pilot said he had stalled "the JetStar on a [FAR] one thirty five ride." Flaps were extended and the landing gear was lowered. Digital electronic engine control (DEEC) recorded a power reduction that remained at idle. According to national track analysis program (NTAP) data, the stall was initiated from an altitude of 5,000 feet. The stick shaker sounded and shortly thereafter, the recording ended. The consensus of 25 witness' observations was that the airplane was flying at low altitude and doing "erratic maneuvers." One witness said it "seemed to stop in midair," then pitched nose down. Some witnesses said that the airplane was spinning. Other witnesses said it was in a flat spin. Still another witness said the airplane fell "like a falling leaf." The airplane impacted marshy terrain in a nose-down, wings-level attitude. Wreckage examination revealed the landing gear was down and the flaps were set to 25 degrees. Both engines' compressor/turbine section blades were gouged and bent in the opposite direction of rotation, and there were rotational scoring marks on both cases. No discrepancies were noted.