North Las Vegas

The pilot departed on runway 06 with zero degrees of flaps. A witness said that she noticed that the airplane appeared to wobble and shudder, and immediately went into a steep right bank turn right after takeoff. The airplane then went into the clouds which were 200 to 400 feet agl. Radar data indicated that the airplane made several 90 degree turns prior to impacting the mountainous terrain 2.55 nm from the departure end of the runway. The pilot normally used 20 degrees of flaps for takeoff. A test pilot said that the airplane handles significantly different during takeoff if zero degrees of flaps are used verses 20 degrees of flaps. The upper cabin's entry door was found, with the locking handle and locking pins, in the closed position. No preimpact engine or airframe anomalies, which might have affected the airplane's performance, were identified.

After climbing to 18,400 feet msl, the pilot reported a turbocharger problem and reversed course. He said he 'may lose the left engine' and that he was unable to maintain altitude. He diverted to an alternate airport. During a right turn onto final approach, the airplane was observed to cross (overshoot) the extended centerline of the runway. It continued in a right turn back toward the centerline, and then entered a left turn to intercept the inbound course. The turn steepened, and then the airplane entered a spin and crashed 1/2 mile short of the runway. A warped flange and evidence of exhaust gas leakage were found on the Inconel exhaust system Wye collector, at the wastegate outlet of the left engine. Neither propeller was in a feather position. There was evidence that the left engine was providing low power during impact. A note on the pilot's clipboard indicated that the (left engine) fuel flow and cylinder head temperature went to zero, and the manifold pressure dropped to 10 inches. The note also indicated that the pilot switched the 'boost pump' to high, the fuel flow went to 260 psi, and manifold pressure increased to 18.5 inches. Calculations showed that the airplane's gross weight (GW) and center-of-gravity (CG) were 7,645 pounds and 158.32 inches. The maximum allowable GW and CG were 7,450 pounds and 158 inches. During impact, the flaps were fully extended. The 'Engine Inoperative Landing' procedure stated, 'Wing Flaps - DOWN when landing is assured.' Most of the pilot's flight time in the Cessna 421 was before 1985; no record was found of recurrent training in the airplane since 1984. Annual and turbocharger inspections were made at 78 and 120 flight hours, respectively, before the accident, but no logbook entries were made concerning maintenance or replacement parts for the exhaust system. All eight occupants were killed.

The commuter flight was enroute to its home airport and over mountainous terrain when it encountered low ceilings and rain showers. The airplane was not certificated for ifr commuter flights. Instead of going to an alternate airport the pilot attempted to maintain visual conditions and requested and received a visual clearance into the tca and advised the controller that his altitude was 5,100 feet msl. His radio transmission became garbled during the clearance read back and shortly thereafter the controller observed the airplane's radar target turn left from its westerly track and disappear from his scope. There were no further communications between the pilot and the controller. When the aircraft failed to arrive at its destination an alnot was issued. Early the next morning the aircraft's wreckage was found impacted in a mountain approximately 10 miles south of course at an elevation of 4100 feet msl. The investigation revealed that the pilot had previously and successfully flown the accident airplane in ifr conditions.

A mechanic, who was not rated as a pilot, took the aircraft without permission and elected to takeoff at night. A witness saw the aircraft departing at about 0250 pdt. Subsequently, it crashed approximately 3 miles east-northeast of the airport in an open undeveloped area. The time of the accident was not determined, but a clock in the wreckage had stopped at 0355. There was evidence the aircraft had impacted in a nose down, inverted attitude while on a north-northeast heading. The aircraft moved only 28 feet after impact and came to rest inverted with the gear extended and the flaps retracted. No preimpact mechanical problem was found. Toxicology tests showed the pilot had a blood/alcohol level of 3,7‰ and a vitreous/alcohol level of 3,3‰. No record was found to indicate that he had engaged in any previous formal flight training. There was evidence the pilot had been under recent stress. A friend reported the pilot and his wife were 'breaking up.' The pilot's wife reported he had a drinking problem which was the reason for their separation.

While on a day/VFR flight from Ontario, CA to Las Vegas, NV, the aircraft collided with mountainous terrain near the top of a 6,500 feet peak. Radar data showed that approximately 20 minutes before the accident, the aircraft began a gradual descent from about 10,000 feet. No preimpact part failure or malfunction of the aircraft, engine or autopilot was found. The pilot had a rest period on the previous day, but the investigation did not determine whether he had obtained any sleep before a 1700 pst flight. After the 1700 pst flight, he voluntarily flew on a late night flight with another company. That flight was delayed in returning and did not land at Ontario until about 0500 pst the next morning. Approximately 41 min later, the pilot took off on the accident flight.

After takeoff from runway 25, at an altitude of 100 feet above ground level, the aircraft pitched up and reached a maximum pitch attitude of 50° to 75°. The aircraft crossed the highway while climbing to an altitude of about 400 feet, 2,000 feet from the departure end of the runway. It then began what witnesses described as a 'wingover' or 'sudden violent nose down turn' to the right, recrossed the highway and crashed in an almost level pitch attitude while in a slight right bank and a slight left yaw. Witnesses to the accident were attracted to the aircraft by the high pitch attitude after takeoff. During the post takeoff maneuver, the engines were reported to be running at a high power setting. The aircraft crashed about one minute after the takeoff roll began; it came to rest in an open field about 1,150 feet past the departure end of the runway and about 650 feet to the right of the runway. The impact heading was 025° magnetic. All 10 occupants were killed, among them Australian tourists.