CESSNA 182D

Full Narrative

HISTORY OF FLIGHTOn October 15, 2016, at 1552 Pacific daylight time, a Cessna 182D airplane, N8718X, impacted the northeast face of Red Peak in the Desolation Wilderness near South Lake Tahoe, California. The private pilot sustained fatal injuries, and the airplane was destroyed. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Instrument meteorological conditions prevailed in the area of the accident site, and no flight plan was filed for the personal flight, which departed Winnemucca Municipal Airport (WMC), Winnemucca, Nevada, about 1320, with a planned destination of Westover Field/Amador County Airport (JAQ), Jackson, California.

The pilot was returning from a hunting trip, and initially departed Lemhi County Airport (SMN), Salmon, Idaho, on the morning of the accident. He landed at WMC, where he serviced the airplane with 41 gallons of 100LL aviation gasoline. Before departing, he spoke with his wife and stated that the landing at WMC was challenging due to gusting wind conditions.

After departing on the accident flight, the pilot took two digital photographs, which he sent to his wife as text messages. The photographs were taken at 1329 and 1336, and their GPS-derived positions and altitudes were contained within the metadata. The photographs were taken about 9 and 18 miles southwest of WMC at altitudes of 6,755 ft and 8,986 ft, respectively, and included views to the south-southeast. (See figures 1 and 2.) The photographs captured areas of mountainous terrain with peaks that appeared about level with the airplane's altitude. Dust clouds could be seen in an adjacent valley, with the dust reaching elevations above the airplane. To the south, in the general direction of the flight, the area was enveloped with dust and/or virga. Both photographs included overcast cloud layers, with openings to the south, through which multiple layers of lenticular clouds could be seen.





Figures 1. 2. Photographs Taken by the Pilot at 1329 (left) and 1336 (right).


At 1338, Air Route Surveillance Radar based in Fallon, Nevada, acquired a target which was using a transponder code of 1200 and traveling southwest at a mode C reported altitude of 9,500 ft, which corresponded with the airplane's position and route. During the next 13 minutes, after passing 6 miles north of the 9,836 ft summit of Star Peak, the target made a 360° left turn descending to 7,600 ft and then climbing back to 8,600 ft.

The target then proceeded southwest for the next hour at altitudes ranging between 8,700 ft and 11,200 ft; at 1450, the pilot's wife received a text message from the pilot stating that he was at Pyramid Lake, and "79 knots."

The target reached the northeast outskirts of Reno, Nevada, at 1454; about that time, the pilot initiated radio contact with Oakland Air Route Traffic Control Center (ZOA), and requested visual flight rules (VFR) flight following. He was provided a transponder code of 3726, and a few seconds later, the 1200 code target switched to a code of 3726. The airplane continued on the southwesterly track, and at 1457, the ZOA controller provided the pilot with a new frequency, transferring the airplane to Northern California Terminal Radar Approach Control (NCT). After establishing radio contact with NCT, the pilot reported his altitude (10,600 ft) and destination and was provided an altimeter setting.

About 2 minutes later, the pilot of an Air Tractor AT-802 (callsign Tanker 874) reported over the same frequency that he was over Pyramid Lake (about 14 miles north of the accident airplane's location) at 8,200 ft and was inbound for "Reno" airport. The pilot of an Aero Commander 690A airplane then reported to NCT that he was also over Pyramid Lake, was inbound for Reno/Stead Airport, and was looking for Tanker 874. Over the next few minutes, the NCT controller issued a wind advisory to Tanker 874 for Reno International Airport, reporting wind from 200° at 31 knots, gusting to 41 knots. The pilot of Tanker 874 stated that his intention was to land at Reno/Stead Airport, rather than Reno-Tahoe International Airport, but that the wind was "not good". He stated that he would track the progress of the Aero Commander, and then divert to Reno International if the wind conditions were not favorable.

During those communications, the accident airplane progressed at an altitude of about 10,700 ft while remaining on a track of 220° and a ground speed of about 60 knots. At 1507, the accident pilot asked the NCT controller if a temporary flight restriction (TFR) over Carson City, Nevada, was still in effect. The controller responded that it was, but that it should not be a factor because the TFR ceiling was 10,000 ft. (See figure 3.)





Figure 3. Temporary Flight Restriction (green) Underneath the Route of Flight

By 1522, the accident airplane was 12 miles south of Reno, and the NCT controller initiated a handoff back to ZOA and provided the pilot with the appropriate frequency. The pilot read back the frequency correctly; however, the pilot did not contact ZOA.

The airplane continued on the same general southwesterly track; over the next 29 minutes, the ZOA controller made four attempts to contact the pilot and requested that NCT do the same. No response was received by either facility, and radar contact was lost at 1551.

Review of the radar data indicated that, at 1543, as the airplane crossed the western shore of Lake Tahoe (elevation 6,229 ft) within about 8 miles of the peaks of the Desolation Wilderness area (elevation 9,983 ft), it began to veer left and then right with accompanying oscillations in altitude between 10,100 ft and 10,900 ft. For the last 96 seconds, the airplane descended from 10,800 ft to the last recorded altitude of 9,700 ft, about 3/4-mile northeast of the 9,311-ft summit of Red Peak. (See figure 4.)





Figure 4. Flight Path During the Final Stages of Flight (the white lines are direct connections between each acquired radar target and do not represent the airplane's actual flight path between targets)

Controllers from both facilities continued their attempts to establish contact with the pilot, and with no response, an alert notice (ALNOT) was issued at 1839.

Review of the radar data for the last 2 hours of flight indicated that the airplane traveled a straight-line distance about 135 miles, which yielded a ground speed that was about half the airplane's normal cruise speed. (See figure 5.)






Figure 5. Radar-acquired Route of Flight (blue indicates 1200 transponder code, red indicates 3726 transponder code)

Snow, rain, and strong wind conditions hampered the search effort, and the wreckage was discovered 3 days later, covered in snow at an elevation of 8,630 ft, about 3,300 ft south of the last radar target and about 50 miles from the destination airport, JAQ. PERSONNEL INFORMATIONThe pilot held a private pilot certificate with an airplane single-engine land rating, issued in 1988. He held a third-class Federal Aviation Administration (FAA) medical certificate issued on February 16, 2015, with no limitations or waivers. He did not hold an instrument rating.

Review of the pilot's logbook revealed a total flight experience of 1,151.6 hours as of July 2, 2016. Most of his experience was in the accident airplane, which he purchased in 2005. His most recent flight review was on May 3, 2015, in the accident airplane.

According to the pilot's wife, the pilot typically flew between California and Idaho six or seven times per year, which required crossing the Sierra Nevada mountain range. His mountain flying experience also included multiple trips requiring passage over the Trinity Alps, Marble Mountains, the Cascades, and the mountainous terrain of southern California, South Dakota, Wyoming, Montana, and Washington.

According to his wife, the accident flight was one of the rare times he flew without a passenger. She stated that, on occasion, they had flown together in visual meteorological conditions while maneuvering through cloud layers, but he had never flown into clouds, and she was not aware of him flying in instrument meteorological conditions.

The pilot's wife reported that he was generally in good health, and that he was scheduled for a non-critical medical appointment 2 days after the accident. During the phone call from WMC, he did not mention that he was experiencing any physiological issues.

The pilot's wife stated that he had been under a significant amount of stress before the trip, but that at its conclusion, he sounded peaceful, revitalized, and relaxed, and he was ready to come home and get back to work. Regarding his personality, she stated that he was very much an "achiever;" at times could be headstrong; and once he had made up his mind, it was very hard to dissuade him. They had discussed the approaching weather system the day before the flight, and she had suggested he drive back with a friend, but he felt strongly that he should fly. AIRCRAFT INFORMATIONThe airplane was manufactured in 1960 and equipped with a Continental Motors O-470R normally aspirated engine and a two-bladed McCauley constant-speed propeller. The most recent maintenance procedure was an annual inspection, completed on February 20, 2016. At that time, the airframe had accrued 5,467.04 flight hours, and the engine had accrued 364.3 hours since overhaul in 2012. The tachometer indicated 2,462.6 hours at the time of the inspection, and following the accident, it indicated 2,532.5 hours.

According to the Cessna 182D owner's manual, when loaded to its maximum gross weight of 2,650 lbs, the airplane had a service ceiling of 19,800 ft and a maximum cruise endurance at 10,000 ft of 7.1 hours at 118 mph. At that altitude and given standard atmospheric conditions, the climb rates at weights of 2,100, 2,400, and 2,650 lbs were 925, 710, and 560 ft per minute, respectively.

The airplane was not equipped with an autopilot or a supplemental oxygen system. The pilot's wife stated that the pilot had never experienced symptoms of hypoxia and that all flights were flown below 11,500 ft. The airplane was not equipped for flight into known icing conditions. METEOROLOGICAL INFORMATIONA meteorology report was compiled by an NTSB weather specialist. The following is a summary of the complete report, which is contained in the public docket.

Upper Air Charts

The National Weather Surface (NWS) Storm Prediction Center constant pressure charts for 1700 depicted mid-level troughs just east and west of the accident site at 700-hPa. Troughs typically act as lifting mechanisms where enhanced lift, gusty winds, fronts, clouds, and precipitation can occur. Troughs and frontal boundaries near mountainous terrain also act to aid in the mixing of low-level air, allowing for the possibility of low-level wind shear, mountain waves, and turbulence. In addition, at 500-hPa, there was a mid-level trough west of the accident site, while at 300-hPa the accident site was located in the exit region of a jet streak, where enhanced lift, clouds, and precipitation can occur. There was a southwest wind around 50 knots at 700-hPa with the wind becoming westerly by 300-hPa. The wind increased to 80 knots by 500-hPa with a wind speed of 70 knots at 300-hPa above the accident site.

Surface Observations

The two closest official weather stations to the accident site were Lake Tahoe Airport (TVL), South Lake Tahoe, California, located 10 miles east-southeast at an elevation of 6,269 ft, and Minden-Tahoe Airport (MEV), Minden, Nevada, located 22 miles east-northeast at an elevation of 4,731 ft.

From 1153 through 1453, observations from TVL indicated 10 miles visibility, wind generally out of the south-southwest at 17 to 21 knots gusting between 28 and 32 knots, and scattered/broken cloud layers. By 1453, clouds were broken at 4,400 ft agl with a ceiling at 7,500 ft agl.

A special weather observation was issued at 1545, indicating 4 miles visibility, moderate rain, scattered clouds at 2,700 ft agl, and an overcast ceiling at 3,300 ft agl.

At 1553, 1 minute after the accident, TVL reported visibility at 4 miles with moderate rain, scattered clouds at 2,400 ft agl, broken ceiling at 2,900 ft agl, overcast skies at 3,400 ft agl, temperature 8°C, dew point 5°C, and an altimeter setting of 29.87 inches of mercury.

MEV reported similar observations throughout the afternoon, with visibilities ranging from 7 to 10 miles, with a brief period of light rain and 3-miles visibility during the 1415 report.

At 1555, 3 minutes after the accident, MEV reported 8 miles visibility, few clouds at 3,300 ft agl, broken ceiling at 4,800 ft agl, overcast skies at 5,500 ft agl, temperature 9°C, dew point 6°C, and an altimeter setting of 29.87 inches of mercury.

A 1455 observation issued for RNO shortly before the airplane passed over its Class C airspace included wind from 210° at 28 knots gusting to 41 knots, few clouds at 5,500 ft agl, scattered clouds at 7,000 ft agl, broken skies at 8,500, 18,000, and 22,000 ft agl.

The closest weather reporting station to the destination airport, was Placerville Airport (PVF), Placerville, California, located at an elevation of 2,585 ft, 20 miles north of Jackson JAQ (elevation 1,694 ft). An observation at 1555 indicated wind from 190° at 13 knots, gusting to 20 knots, broken clouds at 3,400 and 5,000 ft, and an overcast ceiling at 9,000 ft.

Sounding

The closest official upper air sounding was from Reno, Nevada, located 43 miles northeast of the accident site at an elevation of 4,970 ft. Data derived from the 1700 sounding indicated a freezing level at 10,734 ft, with relatively dry conditions east of the Sierra Nevada mountains and a cloud layer likely near 10,000 ft.

The sounding wind profile indicated wind speeds of 45 knots at 9,000 ft, with several layers of clear air turbulence indicated between the surface and 14,000 ft.

The analysis of the sounding data also indicated that mountain wave conditions were likely near 10,000 ft with updrafts and downdrafts of about 2,645 ft per minute. Mountain wave conditions were also likely at 14,000 and 20,000 ft.

Satellite Data

Visible and infrared data from the Geostationary Operational Environmental Satellite number 15 (GOES-15) indicated that cloud cover at the accident site began around 1153 and rapidly increased in coverage from the Nevada and California border westward during the time of the flight. Lenticular cloud formations between Winnemucca and South Lake Tahoe were also observed.

Based on infrared imagery and the vertical temperature profile provided by the 1700 Reno sounding, the approximate cloud-top heights over the accident site were 18,500 ft at 1545. The visible and infrared imagery indicated that there was extensive cloud cover across the accident site at the accident time, with cloud cover increasing in coverage and height with time. In addition, the lenticular clouds were likely indicative of the mountain wave conditions near the mountainous terrain.

Weather Radar Data

The closest NWS Weather Surveillance Radar-1988, Doppler (WSR-88D) was from Reno, Nevada, (KRGX) located 61 miles northeast of the accident site at an elevation of 8,299 ft. Level II and III radar data for base reflectivity images for the 0.5° elevation scans initiated at 1545, 1548, and 1551 indicated that the airplane flew through 5-30 dBZ base reflectivity values (light to moderate echo intensity) along the route of flight during that period. The precipitation targets moved from southwest to northeast. Due to terrain, the radar signal was likely blocked near the accident site, and it is possible that more precipitation was present in the area than indicated in the images.

The weather radar data indicated that the accident flight likely flew through icing and instrument meteorological conditions while above 10,000 ft msl around the accident time.

SIGMETs

SIGMET November 1 was issued for the accident area before the flight departed and warned of occasional severe turbulence below 15,000 ft msl due to strong low-level winds and mountain wave activity, with strong updrafts and low-level wind shear.

AIRMETs

AIRMETs Tango, Zulu, and Sierra, valid for the accident period and location, were issued before the flight departed WMC and again at 1345. The AIRMETs forecast moderate icing conditions between the freezing level (which was between 6,000 and 11,000 ft msl) and 22,000 ft, instrument meteorological conditions with ceilings below 1,000 ft agl, visibility below 3 miles in precipitation and mist, and mountain obscuration conditions due to clouds, precipitation, and mist.

Area Forecast

The Area Forecast for the northern Sierra Nevada area, issued at 1245 and valid at the accident time, predicted a broken ceiling at 10,000 ft msl with cloud tops at 25,000 ft, widely scattered light rain showers, and a south wind of 35 knots with gusts to 45 knots. The forecast predicted a transition later in the afternoon to an overcast ceiling of 8,000 ft msl, with visibility between 3 and 5 miles in light rain and mist.

Terminal Aerodrome Forecast

TVL was the closest site with a NWS Terminal Aerodrome Forecast (TAF). The TAF valid at the time of the accident was issued at 1028 and included wind from 190° at 32 knots with gusts to 45 knots, greater than 6 miles visibility, a broken ceiling at 6,000 ft agl, and wind shear at 2,000 ft agl with wind from 250° at 65 knots.

National Weather Service High Wind Warnings

The NWS Reno office issued high wind warnings at 0408 for the accident area, with another at 1429 warning of southwest wind between 25 to 35 mph with gusts to 70 mph, and gusts on the Sierra Ridge of up to 115 mph.

Wind and Temperature Aloft Forecast

The NWS Winds and Temperature Aloft forecast for (KRNO), issued at 1259, indicated wind at 6,000 ft from 220° at 38 knots, at 9,000 ft from 220° at 63 knots with a temperature of 4° C, and at 12,000 ft from 230° at 61 knots with a temperature of -1° C.

Weather Research and Forecasting Model Simulation

A Weather Research and Forecasting Model (WRF) simulation indicated that, between 1550 and 1600, the horizontal wind speed increased near the accident site and the top of the mountains from almost 60 knots to above 70 knots. At the airplane's cruise altitude, it would have encountered wind speeds between 50 and 70 knots. The WRF vertical velocity data also indicated that, as the airplane approached terrain, it likely encountered downdrafts with velocities between 1,000 and 1,500 ft per minute.

The relative humidity in the accident area was at or above 90% between 1450 and 1650, and greater than 95% during the last two minutes of the flight.

Pilot Weather Awareness

A search of official aviation weather briefing sources, including Lockheed Martin Flight Service (LMFS) and Direct User Access Terminal Service (DUATS), revealed that the pilot did not contact either source directly.

The airplane was equipped with a Stratus ADS-B receiver, and the pilot was using a cellular data-enabled iPad configured with the ForeFlight "Electronic Flight Bag" application. According to technical representatives from ForeFlight, the application receives weather updates when the iPad is connected to the internet. When not connected, such as is typical when in flight, subscription-free, FAA-sourced weather is ported directly to the application via the Stratus unit using the FAA's Flight Information System-Broadcast network (FIS-B). According to the FAA, weather information provided through FIS-B includes lightning, turbulence, icing, cloud tops, and airport surface observations.

According to representatives from ForeFlight, when the application retrieves weather data, a record of the transaction is logged remotely at the ForeFlight data facility. The application's use of FIS-B weather is never logged remotely at the ForeFlight data facility.

A search of archived ForeFlight information indicated no recent record of the pilot accessing weather information. The last data on record was the route for the outbound flight leg, which was received by ForeFlight on October 8, 2016.

The iPad was recovered from the accident site but sustained significant damage; an assessment of its pre-accident operational status could not be determined.

The airport manager at WMC stated that, although the facility had a pilot's lounge that had a computer with weather system access, the lounge was closed on the day of the accident. (although restroom facilities were available and open). Cellular data service for the pilot's iPad was available in the area of the airport. AIRPORT INFORMATIONThe airplane was manufactured in 1960 and equipped with a Continental Motors O-470R normally aspirated engine and a two-bladed McCauley constant-speed propeller. The most recent maintenance procedure was an annual inspection, completed on February 20, 2016. At that time, the airframe had accrued 5,467.04 flight hours, and the engine had accrued 364.3 hours since overhaul in 2012. The tachometer indicated 2,462.6 hours at the time of the inspection, and following the accident, it indicated 2,532.5 hours.

According to the Cessna 182D owner's manual, when loaded to its maximum gross weight of 2,650 lbs, the airplane had a service ceiling of 19,800 ft and a maximum cruise endurance at 10,000 ft of 7.1 hours at 118 mph. At that altitude and given standard atmospheric conditions, the climb rates at weights of 2,100, 2,400, and 2,650 lbs were 925, 710, and 560 ft per minute, respectively.

The airplane was not equipped with an autopilot or a supplemental oxygen system. The pilot's wife stated that the pilot had never experienced symptoms of hypoxia and that all flights were flown below 11,500 ft. The airplane was not equipped for flight into known icing conditions. WRECKAGE AND IMPACT INFORMATIONThe airplane came to rest on the northeast-facing 45° slope of Red Peak, about 1/2 mile south of Lake Schmidell. The upslope side of the site was surrounded by undamaged pine trees ranging in height from 25 to 100 ft tall, with smaller, freshly-damaged saplings in the opening just below the wreckage. (See figure 6.)

The fuselage came to rest on a heading of about 270° magnetic and sustained extensive crush damage from the firewall to the empennage. The top and bottom of the main cabin were separated, and the remaining structure was fragmented and dispersed around the accident site. The vertical stabilizer came to rest at the base of a 100-ft tall tree and remained attached to the tailcone along with the horizontal stabilizer. The left wing sustained accordion-like crush damage along its entire span and remained partially attached to the cabin structure at its leading edge. The right wing fragmented into multiple pieces, most of which were distributed in the lower site elevations to the northeast.

Due to high wind, snow, and treacherous site conditions, an attempt to recover the airplane shortly after the accident was abandoned. The wreckage was ultimately recovered by helicopter almost 1 year later, in September 2017.






Figure 6. Airplane Wreckage at the Accident Site



Following recovery, the airplane was examined by the NTSB investigator-in-charge and representatives from the FAA, Textron Aviation, and Continental Motors.

Both front seats detached from the airframe. Cargo, including folding chairs, water canisters, coolers, tools, and clothing were dispersed unsecured throughout the airframe remnants, and no webbing or cargo securing straps were located.

The instrument panel was fragmented and most of the instruments were detached. The radios, instruments, and transponder were damaged such that an assessment of their settings and readings before impact could not be determined.

The flight control systems within the cockpit were twisted and entangled within the instrument panel. The flap control lever was in the stowed, 0o flaps position, and the fuel tank selector valve was in the BOTH position.

All flight control surfaces were accounted for, and the elevator remained attached to the horizontal stabilizer at its hinges. The airplane was equipped with a trimmable horizontal stabilizer assembly. The elevator trim actuator was at a length consistent with a 5° stabilizer-down (nose-up) position.

The fuel tank bladders from both wings were exposed and shredded, and both fuel caps were in place at their respective filler necks.

The engine had separated from its mount and sustained extensive damage, liberating most of the ancillary components and crushing the induction manifold and exhaust system. The magnetos were not located; however, fragments of their attachment lugs remained in place at the mounting bolts on the engine.

The carburetor body remained bolted to a section of the induction manifold. Its butterfly valve was intact and remained connected to the throttle cable via its control arm. The only other sections of the carburetor recovered were two fragments of the bowl assembly, one of which contained the needle valve and a section of white float material with its associated hinge.

The top spark plugs were removed; all electrodes exhibited varying degrees of corrosion consistent with long-term exposure to the elements. All spark plug electrodes exhibited worn out-normal operational and wear signatures when compared with the Champion Aviation Check-A-Plug AV-27 chart. Visual inspection of the combustion chambers using a borescope revealed no evidence of foreign object ingestion or valve damage.

The wet-type vacuum pump was disassembled and examined. All vanes were intact and wet with oil, and the inner pump cavity was undamaged. The input drive gear was undamaged and remained attached via its coupling.

Both propeller blades separated from the hub, the partial remnants of which remained attached to the crankshaft flange. One blade exhibited 1- to 2-inch-deep gouges along its entire leading edge, with aft curling and chordwise scratches at the tip. The second blade exhibited diagonal gouges to its front side, with 2-inch-deep leading-edge gouges emanating outwards from midspan. The outboard 9 inches of its tip had detached and curled aft, leaving a serrated tear. ADDITIONAL INFORMATIONThe outer boundary of the Reno/Tahoe International Airport class C airspace incorporated the altitudes between 7,200 and 8,400 ft. The airplane passed over the southeast corner of the airspace at an altitude of about 10,800 ft during the period from 2206 to 2217.

The TFR discussed by the pilot with the NCT controller had been in effect since 1230 the day before the accident. The TFR was in place to allow relief efforts for a wildland fire in the Washoe Valley area of Nevada. Specifically, the restriction included a 5-nautical mile radius from the surface to 10,000 ft, centered 17.9 miles from the Squaw Valley VOR 059° radial. The airplane passed over the southeast portion of the TFR at altitude's varying between 10,500 and 10,800 ft during the period from 1524 through 1530.

According to the pilot's wife, he was a "stickler" about maintaining radio contact with air traffic control and would always switch to ZOA frequency as they approached the Sierra Nevada mountain range on return flights. MEDICAL AND PATHOLOGICAL INFORMATIONThe El Dorado Pathology Medical Group, Placerville, California, performed an autopsy on the pilot; the cause of death was massive blunt force trauma (instantaneous).

The FAA's Bioaeronautical Sciences Research Laboratory performed toxicology testing on specimens from the pilot. The results were negative for all screened drug substances and ingested alcohol. SURVIVAL ASPECTSThe airplane was equipped with an ACK Technologies E-04 series 121.5/406 MHz emergency locator transmitter (ELT), which was installed in February 2014.

The ELT was not located in the recovered wreckage, and its mounting tray had detached from the tailcone. The ELT antenna remained attached to the cabin roof. According to the airframe maintenance records, the ELT battery was due for replacement by September 2018.

The Air Force Rescue Coordination Center received reports of ELT transmissions in the area on the 121.5-MHz frequency, but the Search and Rescue Satellite Aided Tracking system did not receive any 406-MHz transmissions from the airplane's ELT.

Examination of the wreckage revealed that the left front seat (pilot's) lap belt was latched about 2 inches short of its full range. The belt did not appear to be stretched or frayed. Each end of the belt remained attached to its fitting hardware, which had detached from the airframe. The shoulder harness was found knotted and tied up against the airframe. The pilot's wife stated that the pilot always used the lap belt but typically did not use the shoulder harness. She further stated that, on one occasion, while flying in extreme turbulence, the pilot struck his head on the airplane's cabin roof.