COULTERVILLE, CA, USA
N3324R
Cessna 182L
During his preflight weather briefing the instrument rated pilot was advised that VFR flight was not recommended, and was given several pilot reports for overcast conditions and icing in clouds between 9,000 and 13,000 feet along his route of flight. The pilot told the briefer he had already heard the hazardous weather advisories on the transcribed weather recording. Before departure, the pilot told relatives that he planned to navigate under visual flight rules because of forecast icing in clouds, and intended to remain low to circumnavigate areas of weather. However, in the hour following takeoff, radar data showed the aircraft turning and circling as it climbed approximately on course and eventually reaching 13,700 feet (msl) in proximity of the accident site. The Safety Board Meteorologist determined that, at that location and altitude, the aircraft would likely have been in clouds and conditions favorable for supercooled large droplets (SLD) producing a moderate to severe icing environment. The radar data showed the aircraft maneuvering in the area near the accident site and descending from 13,700 feet to 11,100 feet over 7 minutes, and then descending in a left-hand turn from 11,100 feet to 4,900 feet, where radar contact was lost in 3.4 minutes. The wreckage distribution indicated that the aircraft was in straight and level flight at impact with the mountainside. Area residents reported that the mountains were obscured in low clouds with poor visibility and periods of intense rain. The pilot was wearing a nasal cannula oxygen dispensing device.
HISTORY OF FLIGHT On February 14, 2000, about 0945 hours Pacific standard time, a Cessna 182L, N3324R, was destroyed when it impacted mountainous terrain 3 miles northwest of Coulterville, California. The instrument rated private pilot and one passenger were fatally injured. The personal flight was operated by the pilot under 14 CFR Part 91 and no flight plan was filed. Visual meteorological conditions prevailed at Merced, 33 miles south of the accident location. The airplane departed from the Fresno, California, Yosemite International Airport at 0832, destined for Red Bluff, California. Three residents in the area of the accident, who were present on the morning of the accident, reported that, until noon, the mountains were obscured in clouds with poor visibility, and there were intermittent periods of intense rainfall. A search was initiated for an unknown aircraft on the afternoon of February 14, in response to reception of an emergency locator transmitter broadcast. The aircraft was located at 0650 on February 15, 2000. According to a relative, the pilot and his wife spent the night prior to the accident at their (the relative's) home in Fresno. The pilot and his wife arrived in Fresno Sunday afternoon en route from Long Beach, California, to their second home in Whidbey Island, Washington. It was raining on their arrival at Fresno and they stopped there for the night due to unfavorable weather. The pilot checked the weather from the relative's home on Monday morning before departure. He said he was going to go VFR because he didn't want to go high due to icing, and by staying low he could circumnavigate the weather. The pilot said they would land at Redding or Red Bluff (California) and check the weather again from there. The relative was not certain of the route the pilot planned to Redding/Red Bluff but said that the pilot was a "great believer in GPS." He observed them takeoff to the southeast from Fresno and turn out to the east. He thought the pilot might have put Redding in the GPS and gone direct. He also said the pilot was well rested and had no health issues he was aware of. The pilot had made the trip between Long Beach and Whidbey Island many times. PERSONNEL INFORMATION According to the pilot's logbook, the pilot flew 30.9 hours in the previous 90 days, which included 13 hours of actual instrument flight time and 5 instrument approaches. A summation error in the logbook made in October 1990, and carried forward, resulted in the pilot-in-command hours shown in the logbook being 66 hours more than actual. AIRCRAFT INFORMATION According to personnel at Mercury Air Center in Fresno, the aircraft was fueled to capacity on Sunday, February 13, with 43.1 gallons of grade 100LL fuel. The aircraft and engine logbooks were not located after the accident. METEOROLOGICAL INFORMATION A Safety Board Meteorological Specialist prepared a Meteorology Factual Report that is attached. The synopsis described a low pressure system at 992 millibars on the Oregon coast with a cold front extending southeast to a second low (995 millibars) over northwestern Nevada and then bowing back to the southwest. The cold front was depicted in the immediate vicinity of the accident site at 1000. The radar summary chart issued at 0935 depicted a large area of rain showers over northern and central California with intensities ranging from light-to-moderate to strong-to-very strong echoes. There was no change in intensity or trend indicated. The maximum radar tops reported in the vicinity of the accident site was 22,000 feet. Seventeen pilot weather reports (PIREPS) are cited in the report for turbulence varying from light to severe and light to moderate rime and mixed icing. The infrared radar image taken at 0930 depicted a band of mid level stratiform clouds over the accident site. Using upper air soundings from Oakland, California, and Reno, Nevada, and temperatures from the infrared imagery, the specialist reported the infrared imagery correlated with a cloud top near the accident site near 15,000 feet (msl). The visible satellite image at a higher resolution was used by the specialist to identify the cloud band obscuring the accident site as "nimbostratus." In Section 16.0, Icing Environment Calculations, the specialist wrote, "The aircraft then was observed from [0922] through [0934] operating in an area of reflectivity of 6 to 11 dBZ. Based on the assumption that the supercooled liquid water content is a constant at 0.5 grams per cubi[c] meter and the droplet concentration remained constant within a reasonable range (near 100 per liter)[t]he attached figure 20 [to the specialist's report] then provides an estimate droplet size of 175 to 240 microns [] in diameters, which is in the range of know[n] moderate to severe supercooled large droplet (SLD) icing environments." In Section 14.0, Preflight Weather Briefing, the specialist wrote: "The pilot of N3324N called for the en route weather to the Rancho Murieta Automated Flight Service Station (AFSS) between 1523Z [0823 PST] and 1529Z [0829 PST] on February 14, 2000. The transcript of that briefing and the weather data used is included as attachment 18 [to the Specialist's report]. Once the pilot identified his planned route at 8,000 feet, the AFSS briefer advised that VFR flight was not recommended. The pilot of N3324N acknowledged the AFSS briefer VFR restriction by stating "right." The AFSS briefer advised that the route was under a SIGMET, and the pilot of N3324N acknowledged he had just listened to the advisory on the TWEB broadcast. The AFSS briefer continued and mentioned "that's how all AIRMETs are" without providing any detail to the specific advisories on turbulence, icing and IFR conditions. The AFSS briefer then provided a mixture of present and forecast conditions between Fresno and Olympia. The AFSS briefing referred to several pilot reports of the overcast conditions and light to moderate rime icing between 9,000 and 13,000 feet. The briefing ended with a report of navigation aids, notice to airmen, and with the pilot of N3324N indicating he would send back a pilot report of conditions encountered." WRECKAGE AND IMPACT INFORMATION The accident site was on the southern face of Penon Blanco Peak located on the eastern side of the central San Joaquin Valley in the foothills of the Sierra Nevada Mountains. Terrain in the area sloped upward to the west, north and northeast, toward the peak, 2 miles north at 2,878 feet. To the south and southwest the terrain descended toward the lower foothills and the San Joaquin Valley. Lake McClure was visible about 3 miles south. The site was at latitude 37 degrees 43.85 minutes north and longitude 120 degrees 15.47 minutes west (GPS). The (GPS) elevation was 2,400 feet msl. The entire aircraft was present and there was no fire. The wreckage was distributed over approximately 100 feet on a magnetic course of 020 degrees. Terrain in the immediate area sloped upward approximately 10 degrees to the north. The aircraft impacted in an area of large, irregular boulders and Toyan and Chamise shrubs, typically 5 feet tall. At the southern end of the debris field, shrubs about 5 feet tall exhibited a horizontally level, fresh injury near the top over a lateral distance approximately equal to the aircraft wingspan with deeper injury in the center. Proceeding northeast along the wreckage path, the shrubs were broken at a progressively lower height along a horizontal plane that intersected the ground about 30 feet north of the initial impact point. At 20 feet, the aircraft's nose wheel assembly was laying on the ground, and at 25 feet, a boulder about 4 feet in diameter exhibited a glistening appearance and had small pieces of metal embedded in the southern face. To the right of the nose wheel about 15 feet, a tree exhibited fresh injury about 6 feet above the base, and plastic components identifiable with the right wingtip were found near the base. At 40 feet along the debris path and 5 feet to the right of center, was the propeller assembly. The blades remained attached to the hub and the propeller mounting bolts were sheared at the interface between the propeller hub and the engine propeller shaft. One propeller blade exhibited gouges 1 to 2 inches deep in the 12-inch span near the tip accompanied by torsional twisting and abrasion along its span. The second blade was bent smoothly aft 90 degrees along its span, and exhibited abrasion, gouging, and twisting within 10 inches of the tip. At 50 feet along the debris path was a boulder approximately 6 feet high and 10 feet wide that had paint and plastic debris embedded in the southwest face. The fuselage was lying immediately west of the boulder with the left wing on top of it. The cabin area of the fuselage was destroyed aft to the baggage compartment. The right wing was lying inverted about 10 feet southwest of the boulder. The empennage control cables were continuous to the aft cabin pulleys and the aileron cables were continuous to the wing root. The engine was lying inverted, about 10 feet to the right of the boulder. The carburetor and intake and exhaust systems were absent from the bottom of the engine. The oil sump was collapsed and deformed in a front-to-rear direction. The cylinder head of the number 6 cylinder exhibited impact damage. The muffler, lying near the base of the boulder, was crushed flat. With the heat shroud removed, there were no cracks or discoloration in the muffler case. To the northeast of the boulder, over about 50 feet, was a debris field of miscellaneous small items and papers. MEDICAL AND PATHOLOGICAL INFORMATION According to a Mariposa County Sheriff's Deputy, who was among the initial responders, the pilot was found wearing a nasal cannula oxygen dispensing. An autopsy was performed on the pilot by the Mariposa County (California) Sheriff/Coroner, case number 00-013, MG0000324. A toxicological analysis was performed by the Federal Aviation Administration (FAA) Civil Aeromedical Institute, Oklahoma City, Oklahoma. TESTS AND RESEARCH Two types of recorded radar data were obtained from the FAA Southwest Region Quality Assurance Office. Copies of the data are attached. Continuous Data Recording (CDR) data was provided by the Fresno Terminal Radar Approach Control for the first 33 minutes of the flight after takeoff. The aircraft is first observed near the departure airport, on a discrete transponder code (0131), at 08:36:51 climbing through 400 feet (msl). In the ensuing 25 minutes, the aircraft is recorded climbing to 4,500 feet on a west-northwesterly heading. When about 5 miles southwest of the town of Chowchilla, the data showed the aircraft making a climbing left turn, after which it proceeded on a northerly heading. The CDR recorded data ends at 09:10:35 when the aircraft is about 5 miles northwest of Chowchilla climbing northbound through 7,900 feet. National Track Analysis Program (NTAP) data was provided by the Los Angeles Air Route Traffic Control Center for the later portion of the flight. The NTAP data began at 09:05:27 when the aircraft was southwest of Chowchilla, turning northbound, and climbing through 5,700 feet. In the ensuing 28 minutes the data showed the aircraft, then on a VFR (1200) transponder code, climbing on the northerly heading until 09:33:29, when the aircraft was approximately 5 miles northwest of the accident site at 13,700 feet. In the next 7 minutes the data showed the aircraft maneuvering in the area 3 to 5 miles northwest of the accident site and descending to 11,100 feet. At 09:41:18, the data showed the aircraft, then at 11,100 feet about 2 miles northwest of the accident site, made a right turn, then descended abruptly in a left-hand turn through a southerly heading, until radar contact was lost at 09:44:42 at 4,900 feet. The last radar contact was approximately 2 miles southwest of the accident location. ADDITIONAL INFORMATION The aircraft wreckage was released on April 13, 2000 to Mr. Alejandro Galioto, Claims Representative for AIG Aviation Insurance Services.
The pilot's attempted flight into known adverse weather after receiving hazardous weather advisories, which resulted in inadvertent flight into instrument meteorological conditions while attempting to maintain VFR conditions on top. The subsequent accumulation of structural icing required an emergency descent into conditions of low cloud ceilings and obscured mountains.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
