N6234G

On September 2, 1995, at 0838 hours mountain standard time, a Cessna 421C, N6234G, collided with hilly desert terrain about 1/2 mile northeast of the approach end of runway 19 at the Mesquite Airport, Mesquite, Nevada. The accident site is located about 600 feet east of the state boundary in Arizona, about 5 miles west of the community of Beaver Dam. The airplane was destroyed by impact forces. The certificated airline transport pilot and seven passengers all received fatal injuries. The airplane was being operated as a corporate/executive flight by Adventure Airlines L.L.C., Las Vegas, Nevada, under 14 CFR Part 91 when the accident occurred. The flight originated from the North Las Vegas Airport (VGT), Las Vegas, Nevada, at 0726 hours and was destined for West Yellowstone (WYS), Montana. Visual meteorological conditions prevailed at the time and an instrument flight rules (IFR) flight plan was filed.

At 0706 hours the pilot contacted the Reno Flight Service Station and requested a standard weather briefing for his route from the North Las Vegas Airport to West Yellowstone. After receiving the weather briefing the pilot filed an IFR flight plan.

The director of maintenance for Adventure Airlines L.L.C., assisted the pilot in preparing the airplane for the flight. He indicated that he checked the airplane fuel caps for security and the fuel tanks for quantity. He noted that all the fuel cells were full; to include the wing locker tank in the left engine nacelle. The airplane was loaded at the Adventure Airlines L.L.C., facilities at the North Las Vegas Airport about 0715, and taxied about 0720 hours. After takeoff at 0741 hours, the pilot contacted the Los Angeles Air Route Traffic Control Center (LAX ARTCC) and reported climbing to 17,000 feet. LAX ARTCC sector controller obtained information concerning the destination of the flight from the pilot and then coordinated a higher altitude and direct routing. At 0748 hours, the sector controller cleared the flight to FL210. At 0756 hours, the sector controller cleared the flight direct to West Yellowstone.

At 0806 hours, the pilot contacted the LAX ARTCC sector controller and requested clearance to return to Las Vegas. According to radar data the airplane was at FL184 and at a position about 98 nautical miles northwest of North Las Vegas Airport. The sector controller issued a clearance to return to Las Vegas and asked the pilot if he would like to declare an emergency. The pilot indicated he was not declaring an emergency at this time and reported an unspecified turbocharger problem.

At 0808 hours, the pilot requested a slow descent to 14,000 feet mean sea level (msl). The sector controller issued a descent clearance to 14,000 feet msl at the pilot's discretion. At 0811 hours, the pilot advised the sector controller he "may lose the left engine," and was unable to maintain altitude. At 0819 hours, the pilot declared an emergency and reported eight people onboard with 3.5 hours of fuel left.

At 0821 hours, the LAX ARTCC sector controller advised the pilot of the location of the Mesquite Airport, and subsequently issued a radar vector. The airplane was at a position 25.2 nautical miles northwest of the Mesquite Airport. Radio contact with the airplane was lost as it descended below 6,500 feet above msl. Communications with the accident airplane were relayed to the LAX ARTCC by a Skywest Airlines commuter flight. The Skywest Airlines flight was orbiting at 10,000 feet msl northeast of the Mesquite Airport at the request from LAX ARTCC. Radar contact was lost with the accident airplane as it descended below 5,000 feet msl.

The first officer from the Skywest Airlines observed the accident airplane in a right turn fly past the extended centerline of the runway 19. The accident airplane continued the right turn back to the runway extended centerline. The accident airplane then turned left, as to intercept the final approach course. According to the Skywest Airlines first officer, the accident airplane continued the left turn past the centerline. The accident airplane's angle of bank became steeper. The first officer told investigators the airplane entered a spiral that tightened into a nose-low spin. The airplane spun three to four times before hitting the ground.

Witnesses on the ground reported seeing the airplane flying between 200 to 250 feet above the ground. The airplane then banked from left to right, and then climbed straight up while turning. The airplane then reached an altitude of 400 to 450 feet AGL where, according to a witness, it stalled, descended out of control, and spun to the ground.

One of the witnesses drove to the Mesquite Airport and reported his observations to airport personnel. The witness led the personnel to the area where he last saw the airplane and discovered the wreckage. There were no survivors.

Pilot Information

The pilot held an airline transport pilot certificate for multiengine airplanes which was issued on October 15, 1987, as the result of issuance of an additional type rating in the Douglas DC-3. The pilot also held a commercial pilot certificate for single-engine airplanes and helicopters which was issued on March 1, 1972, on the basis of military competence. The pilot received his first military rating on October 20, 1969, from the United States Army.

The most recent second-class medical certificate was issued to the pilot on April 25, 1995, and contained the limitation that correcting lenses be available for near vision while exercising the privileges of his airman certificate.

The pilot's aeronautical experience listed in this report was obtained from a review of the pilot's most recent logbook dated from March 23, 1981, to present. In addition, information was obtained from a review of Adventure Airlines L.L.C., forms found in the accident airplane, the pilot's resume, and FAA airmen records on file in the Airman and Medical Records Center located in Oklahoma City, Oklahoma.

The pilot's total aeronautical experience consists of about 18,624 hours, of which about 14,390 hours were in multiengine airplanes. Review of available records revealed approximately 86 hours were accrued in the Cessna 421C, of which 56.7 hours were accrued prior to the end of 1984.

Review of the pilot's employment history revealed most of the pilot's multiengine flight experience was gained in the Convair CV600/640, the Douglas DC-3, and the Dehavilland DHC-6. The pilot satisfactorily completed an airman competency/proficiency check on May 20, 1995. The flight check was administered by the pilot's previous employer's check airmen in a Beech King Air 90. According to the FAA, the completion of the flight check is regarded as equivalent to the requirements for the completion of a biennial flight review, and would allow the pilot to act as pilot-in-command of a Cessna 421C.

In the preceding 90 and 30 days prior to the accident, the Adventure Airlines L.L.C., forms listed a total of 29.1 and 20.1 hours, respectively, flown in the Cessna 421C by the pilot. There was no record found of the pilot receiving any formal recurrent training in the Cessna 421C since 1984.

Airplane Information

The Cessna 421C, serial number 421C0264, was manufactured on April 4, 1977, and was acquired by Adventure Airlines L.L.C., on April 13, 1995, for use as a corporate aircraft. The airplane was configured with a 28.4 gallon wing locker fuel cell in the left nacelle and a baggage compartment in the right nacelle. The airplane was not used for air tours and, therefore, was not listed on Adventure Airlines on-demand air taxi certificate. The airplane was operated and maintained under 14 CFR Part 91. The airplane had accumulated a total time in service of 5,461 flight hours. Examination of the maintenance records revealed that the most recent annual inspection was accomplished on April 1, 1995; 78 flight hours before the accident.

Two Teledyne Continental GTSIO-520L engines were installed in the airframe. According to the airframe manufacturer, the engines produce 375 horsepower at 39 inches of manifold pressure up to an altitude of 20,000 feet. The pilot operating handbook (POH) lists a 255- to 275-pound-per-hour fuel flow for takeoff and climb to an altitude of 18,000 feet.

On September 2, 1995, the left and right engines had accrued a total in service time of 2,751 hours, respectively. The maintenance records note that major overhauls were accomplished on both engines 1,156.4 flight hours before the accident. Annual inspections on the engines were accomplished on the date specified above for the airframe.

Turbocharger Operation

Each engine is equipped with a turbocharger system that allows rated power to 20,000 feet. According to the airframe manufacturer, anything that affects the flow of induction air into the compressor, or the flow of exhaust gases into the turbine, will increase or decrease the speed of the turbocharger. The POH for the airplane states; " When the wastegate is closed, any change in the turbocharger speed will mean a change in engine operation. Anything that causes an increase or decrease in turbine speed will cause an increase or decrease in manifold pressure. If turbine speed increases manifold pressure increases; if turbine speed decreases, manifold pressure decreases. Any change in exhaust flow to the turbine or ram induction air pressure, whether it is an increase or decrease, will be magnified approximately 8 to 10 times by the compression ratio and the change in flow through the exhaust system."

Weight and Balance

The maximum certified gross takeoff weight for the accident airplane was 7,450 pounds. The center of gravity limits for takeoff are between 152.6 to 158 inches. The airplane was last weighed on February 14, 1994. The airplane's empty weight was listed at the time as weighing 5,264 pounds with a useful load of 2,186 pounds. The moment was listed at 795,88...