Accident Details
Probable Cause and Findings
Fuel starvation due to the pilot's failure to adequate monitor the aircraft's fuel system and select a tank containing fuel in a timely manner. The pilot's failure to monitor the fuel system was due to the effects of hypoxia. Factors in the accident were the pilot's failure to obtain a preflight weather briefing, his inadequate preflight planning/in-flight decisions, and his lack of familiarity with the mountains.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHT
On February 19, 1996, at 1315 hours Pacific standard time, a Beech C35, N2PA, collided with mountainous terrain in the Sierra Nevada Mountains near Lee Vining, California, following a loss of engine power. The aircraft was owned and operated by the pilot and was on a personal cross-country flight from Las Vegas, Nevada, to Oakland, California. Instrument meteorological conditions prevailed in the area of the accident site. The pilot filed and received an IFR clearance while in flight. The aircraft was destroyed in the collision sequence and the private pilot, the sole occupant, sustained fatal injuries.
During the investigation, recorded radar data and all known voice air-to-ground communications were obtained from the involved Federal Aviation Administration (FAA) facilities for detailed review. The radar data was provided in two formats consisting of the National Track Analysis Program (NTAP) and Data Analysis Reduction Tool (DART). The DART data was requested in both a Log Sort and Track Sort version. All recorded air-ground communications between the aircraft and the ground stations were examined in both a written transcript version, and by listening to the certified re-recordings of the actual tapes. Information discussed in the pertinent portions of this narrative report were derived from the above sources. The radar data and communications transcripts are appended to this report. The re-recordings of the communications tapes are included in the docket for this accident.
Initial information provided to the Safety Board led investigators to believe that the flight originated in Tonopah, Nevada, on the morning of the accident. Subsequent inquiries disclosed that the flight in fact originated from McCarran International Airport, Las Vegas, Nevada, on the morning of the accident. At the time this information was revealed, 14 days had elapsed and the FAA air-ground communications recording mediums at McCarran had been recycled so the flight's exact departure time was not available. The estimated departure time of 1050 PST was reconstructed based on a review of records obtained from the Fixed Base Operator (FBO) where the aircraft was parked while at McCarran, and time elements based on aircraft performance data, times of ATC contact over the Coaldale VOR, the known upper air winds, and ground speeds obtained from the recorded radar data.
Records obtained from Eagle Flight Services, Inc., at McCarran International Airport disclosed that the aircraft arrived on February 16 and departed on February 19, 1997. The sales ticket for payment of services provided was date and time stamped on February 19 at 1030.
Review of National Weather Service and FAA Flight Service Station (FSS) facility records disclosed no evidence of a preflight weather briefing under either the aircraft registration number or the pilot's name.
At 1204 the pilot contacted the FAA Reno FSS by radio, stated the flight's position as over the Coaldale VOR, and requested only the current Oakland weather. The briefing specialists provided the current and forecast weather, in addition to the area forecast and flight advisories in effect for the route of flight between Coaldale and Oakland. During the exchange, the specialists reported that airmets were in effect for mountain obscuration, moderate turbulence, and moderate mixed icing conditions from the 10,000 foot freezing level to 20,000 feet. The pilot responded that he had been "at 10,000 to 12,000 feet since leaving Las Vegas" and had experienced only light chop.
Ten minutes later the pilot contacted Reno FSS again by radio and air-filed an IFR flight plan to Oakland from Coaldale VOR via Victor (airway) 244 direct Oakland. Thirteen thousand feet was requested as the cruising altitude and the pilot reported 4 hours of fuel onboard.
The pilot's first radio contact with Oakland Air Route Traffic Control Center (ARTCC) was at 1217 when he reported his position as "13 DME south of the Coaldale VOR" and requested to pick up his IFR clearance to Oakland. The sector controller identified the aircraft's radar position as 5 miles southwest of the VOR and inquired what altitude the pilot requested as his final cruise altitude. The pilot responded with "one thousand four thousand." The controller then issued the pilot an altitude assignment to maintain 16,000 feet. At the same time, the controller also amended the pilot's route to present position direct Panoche VOR, Victor (airway) 301 to Sunol intersection, thence direct to Oakland. According to an aeronautical chart, the course line of that routing to Panoche is 25 degrees left of the 250 degree outbound radial of the Coaldale VOR, which defines Victor 244. The pilot responded that he was having difficulty finding Panoche and asked the controller "can you give me a hand." The controller provided the pilot with a 225-degree heading assignment and instructed him to "proceed direct Panoche when able."
Ten minutes later at 1235, the pilot made the first of many subsequent requests for a clearance to a lower altitude. The controller responded that 16,000 feet was the lowest Minimum Vectoring Altitude (MVA), and added that it would be 60 miles before the pilot could get a lower altitude.
Review of the recorded radar data disclosed that during the time frame from 1224 to about 1306, the aircraft's ground track averaged 238 degrees magnetic, which is roughly half the difference between the outbound 250 radial from Coaldale and the 225-degree heading assigned by the controller. According to the DART radar data, the aircraft's ground speed computed by the FAA air traffic system computer was averaging 85 knots. The aircraft's mode C reported altitude was noted as generally 16,000 feet, with occasional 100-foot excursions above and below that altitude until 1301. Between that time and 1312, the mode C reported altitude began a descent to values as low as 15,300 feet.
At 1301, the controller queried the pilot about his altitude and the pilot reported that he was having difficulty holding altitude due to turbulence. In response, the controller cleared the flight to maintain a block altitude between 15,000 and 16,000 feet and noted the flight's radar position as 60 miles west of Coaldale. The pilot then asked again for a lower altitude, to which the controller responded that 15,000 feet was the lowest possible MVA for the next 25 miles. After coordinating with nearby sectors, the controller amended the pilot's clearance at 1306 to present position direct Manteca VOR (along Victor 244, the pilot's original route request) Victor 195 Sunol intersection.
The pilot declared an emergency at 1312:33, reported that the "engine was out," and requested services. The controller responded 4 seconds later that the closest airport was Bridgeport at the pilot's 3 o'clock position at 21 miles. Thirty-seven seconds later the controller advised the pilot that the Lee Vining airport was at his 6 o'clock position 9 miles away and provided a suggested heading of 040 for the airport. The last radio transmission from the aircraft was at 1314:55, and the last transponder return was at 1314:44 at a mode C reported altitude of 13,800, about 4.8 statute miles southwest of the impact site.
The accident site is in rugged mountainous terrain near the top of the 11,697-foot-tall Lee Vining peak at longitude 119 degrees 18.9 minutes west by latitude 37 degrees 50.4 minutes north.
AIRCRAFT INFORMATION
Partial maintenance records limited to the most recent logbooks for the airframe and engine were recovered and examined. No historical modification or alteration records were available. A 1952 production model Beech C35, the aircraft had accumulated a total time in service of 5,556 hours. The most recent annual inspection was completed on October 18, 1995, 45 hours prior to the accident.
Beech production records disclosed that the aircraft was originally delivered without an oxygen system or wing tip fuel tanks. The optional factory fuel system installed on the production line consisted of a 20-gallon main tank in each wing and a 20-gallon auxiliary tank mounted in the fuselage behind the rear cabin baggage area. Each wing tank has a 17-gallon useable capacity, while the auxiliary fuel tank in the fuselage contains 19 useable gallons. The original factory installed engine was a Continental E-185-11.
According to Beech Aircraft, the power plant installation for either the E-185 or E-225 series Continental engines does not provide for an alternate air source for the induction system other than through the carburetor heat system, which is available by activation of a cockpit control lever.
Examination of the wreckage disclosed that a normally aspirated Continental E-225-8 engine was installed in the airframe. Wing tip fuel tanks, which appeared to be of the 15-gallon capacity size, and, a fixed oxygen system were also found installed.
Review of the maintenance records disclosed that the engine was installed in the airframe on April 10, 1972, and had accumulated a total time in service of 2,853 hours, with 1,080 hours since the last major overhaul. At the last annual inspection on October 18, 1995, cylinders 2, 5, and 6 were replaced, and new magnetos were installed. In addition, the entry noted that weld repairs were made to the exhaust tubing.
As noted in the History of Flight section of this narrative, the aircraft was parked while at Las Vegas at Eagle Flight Services, Inc. Records from the FBO disclosed that the aircraft was refueled on February 16th after arrival with the addition of 24.1 gallons of 100 low lead aviation fuel. The records did not disclose into which tanks the fuel was added, and line personnel could not recall any details of the fueling. The fuel quantity distribution in the tanks at arrival in Las Vegas are unknown. Based upon the pilot's statement of "4 hours fuel on board" at the time he file...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# LAX96FA119