# NTSB WPR17FA044: Cessna 182, N52388, Dabob, WA, December 30, 2016 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: December 29, 2016, 18:44 local (Dec 30, 2016, 02:44 UTC) - Place: Dabob, WA - Coordinates: 47.823612, -122.79 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.8236&lon=-122.7900&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Fatal - Injuries: 4 fatal - Status: Completed, report February 26, 2019 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: FAA, Textron Aviation, Continental Motors Group - NTSB case key (mKey): 94548 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR17FA044 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/94548/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=94548 - Page: https://openairdocs.org/ntsb/WPR17FA044 ## Probable cause The non-instrument-rated pilot's decision to continue a night visual flight rules into instrument flight rules conditions, which resulted in spatial disorientation and a loss of airplane control. Contributing to the accident was the pilot's failure to obtain an official weather briefing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause) - [Perception/orientation/illusion: spatial disorientation](https://openairdocs.org/ntsb-findings/02022025): Personnel issues › Psychological · Pilot (probable cause) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause) - [Ceiling/visibility/precip](https://openairdocs.org/ntsb-findings/03035000): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause) - [Planning/preparation: weather planning](https://openairdocs.org/ntsb-findings/02061020): Personnel issues › Task performance · Pilot (probable cause) - [Health/Fitness: use of medication/drugs](https://openairdocs.org/ntsb-findings/02013020): Personnel issues › Physical · Pilot - [Health/Fitness: predisposing condition](https://openairdocs.org/ntsb-findings/02013035): Personnel issues › Physical · Pilot ## Analysis The non-instrument-rated private pilot departed at night on a visual flight rules (VFR) cross-country flight without obtaining an official weather briefing. If the pilot had received an official briefing, he would have been informed of instrument flight rules (IFR) conditions present on his route of flight. Radar data showed the airplane traveling on a heading towards its destination at varying altitudes. The pilot's communications with an air traffic controller indicated that he was trying to avoid restricted airspace, and then, when asked by the controller what his intentions were, the pilot stated that he was trying to stay out of the clouds. As the airplane made multiple 360° turns, the controller attempted to keep the airplane in controlled airspace before losing communications and radar contact with the airplane near the accident site. Examination of the accident site indicated the airplane impacted terrain in a nose-down attitude at a high airspeed consistent with a loss of control. The attitude indicator was disassembled, and scoring was identified suggesting that the gyro rotor was spinning and, therefore, likely operational at the time of impact. There was no evidence found of mechanical malfunctions or failures that would have precluded normal operation of the airplane. Based on upper air data, infrared satellite imagery, and surface observation data, the flight likely encountered precipitation, lowering ceilings, and IFR conditions around the time the airplane began to make the 360° turns. The IFR conditions encountered by the flight were conducive to spatial disorientation, and it is likely that the pilot experienced spatial disorientation and lost control of the airplane. The pilot had depression, anxiety, and insomnia, for which he was prescribed a number of potentially-impairing medications, most of which were identified during postaccident toxicology testing. However, whether these conditions or their treatment contributed to the pilot's poor decision-making in continuing a night VFR flight into IFR conditions or his susceptibility to spatial disorientation could not be determined from the available information. ## Factual narrative Spatial Disorientation According to the FAA Airplane Flying Handbook (FAA-H-8083-3), "night flying is very different from day flying and demands more attention of the pilot. The most noticeable difference is the limited availability of outside visual references. Therefore, flight instruments should be used to a greater degree.… Generally, at night it is difficult to see clouds and restrictions to visibility, particularly on dark nights or under overcast. The pilot flying under [visual flight rules] VFR must exercise caution to avoid flying into clouds or a layer of fog." The handbook described some hazards associated with flying in airplanes under VFR when visual references, such as the ground or horizon, are obscured. The handbook states that, "the vestibular sense (motion sensing by the inner ear) in particular tends to confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in the attitude of the airplane, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time. On the other hand, false sensations are often generated; leading the pilot to believe the attitude of the airplane has changed when in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation." A review of the airplane's logbooks revealed that the airplane, serial number 18262571, had a total airframe time of 2,554 hours at the last annual inspection dated August 11, 2016. The engine was a Continental Motors O-470-R-25A, serial number 451850. Total time recorded on the engine at the last annual inspection was 2,554 hours, and time since major overhaul was 517.2 hours. Refueling records provided by Diamond Service at BFI, revealed that the pilot purchased 10.2 gallons of 100 low lead aviation grade gasoline on the day of the accident. On December 29, 2016, about 1844 Pacific standard time, a Cessna 182P, N52388, collided with terrain near Dabob, Washington. The non-instrument-rated private pilot and three passengers were fatally injured. The airplane was substantially damaged. The airplane was registered to the pilot who was operating it under the provisions of Title 14 Code of Federal Regulations Part 91. Night meteorological conditions prevailed in the vicinity of the accident site, and no flight plan was filed for the personal cross-country flight. The visual flight rules (VFR) flight departed at 1816 from Boeing Field International Airport (BFI), Seattle, Washington, and was enroute to William R. Fairchild International Airport (CLM), Port Angeles, Washington. According to a family member, the pilot, his wife, and two grandchildren flew from CLM to BFI in the morning, spent the day in the Seattle area, and were returning to CLM when the accident occurred. According to air traffic control communications, at 1833, the pilot was transferred from the BFI tower controller to the Naval Air Station Whidbey Island Approach Control West (APW) controller. A reviewof the airplane's radar track (see Figure 1) showed that the airplane departed the BFI area on a northwest heading climbing to about 2,800 ft mean sea level (msl) before descending with altitudes varying between 2,500 ft msl and 2,000 ft msl. At 1833:30, the airplane traveled west into the northern side of restricted airspace P-51. At 1834:04, the APW controller asked the pilot if he was reversing course, and the pilot replied that he was just trying to stay out of the restricted airspace. At this point, the airplane started a 270° left turn at 1,850 ft msl. Halfway through the turn, the airplane descended to 1,025 ft msl or about 600 ft above ground level (agl). The airplane exited P-51 traveling northwest about 1834:44. At 1837:26, the APW controller asked the pilot for his intentions, and the pilot replied that he was trying to stay out of the clouds. The airplane completed a 270° turn at 1,400 ft msl and headed northeast. At 1837:58, the pilot asked for vectors to Port Townsend. The APW controller recommended a 050° heading to get the airplane east of an area where the minimum vectoring altitude was 8,800 ft msl before turning the airplane north toward Port Townsend. At 1839:15, the APW controller instructed the pilot to maintain VFR flight and indicated that Port Townsend was at a heading of 340°; the pilot confirmed that he was turning to 340°. Over the next 5 minutes, the airplane performed two left 360° turns, while its altitude varied between 1,100 ft msl and 2,475 ft msl. At 1840:41, the controller told the pilot he would be unable to fly on that 340° heading to maintain VFR and recommended that he head east. The pilot replied and stated he was heading east. About a minute later, the airplane turned north and the controller asked the pilot his intentions. The pilot stated he was going to turn west to CLM, and the controller informed the pilot he would not be able to maintain radar contact with him. The controller again offered assistance and the pilot responded by stating he was heading towards CLM and thought he may have been out of the clouds. At 1843:30, as the airplane completed the last 360° turn and headed northwest, the controller asked if he was heading towards CLM now, and the pilot responded with "affirmative." At 1844:43, APW lost radar contact with N52388 about 14 miles south of Jefferson County International Airport, Port Townsend, Washington, and about a half mile northwest of the accident site. Figure 1-Radar Track A witness located at his residence, about 800 ft to the southwest of the accident site, reported that he heard an airplane flying southeast then east and that the engine was loud. After radio and radar contact were lost, the FAA issued an alert notice. A search was conducted by the US Navy and a Washington State search and rescue team. The airplane was located on the morning of December 30, 2016, about 1.5 miles south of Dabob, in steep, heavily wooded terrain. Pacific Northwest Forensic Pathologists, Tacoma,Washington, conducted an autopsy on the pilot. The forensic pathologist determined that the cause of death was severe multiple blunt force injuries to the body. The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicology testing on available tissue specimens from the pilot and identified 7-amino-clonazepam, bupropion, and trazodone in muscle. Bupropion and trazodone were also identified in lung. The drug 7-amino-clonazepam is an inactive metabolite of clonazepam, which is a sedating benzodiazepine prescription medication used to treat anxiety and often marketed with the name Klonopin. Clonazepam carries this warning, "Since clonazepam produces [central nervous system] CNS depression, patients receiving this drug should be cautioned against engaging in hazardous occupations requiring mental alertness, such as operating machinery or driving a motor vehicle. They should also be warned about the concomitant use of alcohol or other CNS-depressant drugs during clonazepam therapy." Bupropion is an antidepressant. Trazodone is a sedating antidepressant that may be used to treat insomnia. Trazodone carries this warning, "Antidepressants may impair the mental and/or physical ability required for the performance of potentially hazardous tasks, such as operating an automobile or machinery; the patient should be cautioned accordingly. Trazodone hydrochloride may enhance the response to alcohol, barbiturates, and other CNS depressants." At 1753, the reported weather at BFI included variable wind at 6 knots, visibility 10 miles, light rain, broken ceiling at 1,800 ft agl, overcast skies at 3,000 ft agl, temperature 8°C, dew point 6°C, and altimeter setting 30.13 inches of mercury. At 1835, Bremerton National Airport (PWT), Bremerton, Washington, located about 20 miles south of the accident site, reported, in part, wind calm, visibility 10 miles, overcast ceiling at 600 ft agl, temperature 5°C, dew point 4°C, and altimeter setting 30.15 inches of mercury. Review of infrared satellite imagery from 1845 and 1900 indicated abundant clouds over the accident site at the accident time. The clouds were moving from west to east, and there was a band of clouds oriented west to east over the accident site around the accident time. Based on the brightness temperatures above the accident site and the vertical temperature profile provided by upper air data, the cloud-top heights over the accident site were about 20,000 ft at 1845. Based on the upper air data, infrared satellite imagery, and surface observation data, the flight likely encountered precipitation, lowering ceilings, and instrument meteorological conditions shortly after passing northwestward across Puget Sound. Astronomical data obtained from the United States Naval Observatory for the accident site on the day of the accident indicated that sunset was at 1627, the end of civil twilight was at 1703, and moonset was at 1721. A search of official weather briefing sources,such as Lockheed Martin Flight Service and Direct User Access Terminal Service, indicated that the pilot did not receive an official weather briefing from those sources. A search of ForeFlight weather information revealed that the pilot did not request a weather briefing using ForeFlight Mobile before the flight. It is unknown if the pilot checked or received any other weather information before or during the accident flight. For more information see the Weather Study in the public docket for this accident. The pilot, age 63, held a private pilot certificate with an airplane single-engine land rating. His most recent third-class FAA medical certificate was issued on April 3, 2015, with limitations that he must wear corrective lenses. The pilot reported on the medical certificate application that he had accumulated 700 total hours of flight experience of which 54 hours were in the last 6 months. The pilot's logbook was examined during the investigation, and the entries did not appear to have been updated recently. The last entry in the logbook was dated September 18, 2015. The on-site examination of the wreckage revealed that the airplane came to rest at the base of a draw between two hills that gradually sloped down in a northeast to southwest direction. The debris field from the initial impact to the last piece of wreckage was about 160 ft long and on a magnetic heading of 225°. The first identified point of contact (FIPC) was with three trees at about 30 ft above the ground. The left aileron outboard wing section was found near the base of the trees. The main wreckage consisting of the fuselage, engine, propeller, empennage, and sections from the left and right wings, was located near the end of the debris path. The fuselage was orientated on about a 100° magnetic heading. The forward fuselage and cabin were fragmented and mostly separated. The engine had separated from the airframe and was located near the main wreckage. The propeller had separated from the engine and was found buried in the dirt near the main wreckage. The propeller hub assembly was heavily fragmented and both blades had separated from the hub. Rotational scoring was observed on one of the propeller shanks. Both blades displayed S-bending and about 2 inches of the tip had separated from one blade. The aft fuselage and empennage separated from the main wreckage near the aft cabin area. The separated rudder and vertical stabilizer fragments were located 160 ft northeast of the main wreckage and displayed circular tree strike indentions. The attitude indicator had separated from the instrument panel and was located near the main wreckage. The outer case of the instrument was fragmented. Its gyro was extracted, and rotational scoring was noted. ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) ## Aircraft - Registration: [N52388](https://openairdocs.org/deregistered/N52388-2018-11-19), registration cancelled 2018-11-19, S/N 18262571, built 1973 (OpenAirDocs) - Reported make and model: CESSNA 182 (P) - Registry model: [Cessna 182P](https://openairdocs.org/model/cessna-182p) (registry code 2075816) (OpenAirDocs) - Registry engine: [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series) (registry code 17026, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18262571 - Year built: 1973 - Airframe hours: 2554 - Engines: Continental O-470-R-25A 235 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 11, 2016 - Departed: BFI, SEATTLE, WA - Destination: CLM, PORT ANGELES, WA - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; injuries: fatal; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; toxicology performed; flight hours: 700 total ## Weather - Conditions: Visual (VMC), Night/dark - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 600 ft overcast - Temperature: 41 °F, dew point 39 °F - Altimeter: 30.14 inHg - Observed at: KPWT, 20 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20161229021569A](https://openairdocs.org/incident/20161229021569A), Dec 29, 2016: Cessna 182P, Dabob, WA, Destroyed, 4 fatal. On 12-29-2016 approximately 18:15 PST Cessna 182-P N52388 left Boeing field with 4 on board including pilot. Aircraft was travelling to port angles,… ## Docket (16 files) The files NTSB released with the investigation on December 13, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=94548. 41.4 MB in all. - Weather Study Report (item 1, .PDF, 9.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469455&FileExtension=.PDF&FileName=Weather%20Study%20Report-Master.PDF - Weather Study Report - Attachment 1 (item 2, .GIF, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469456&FileExtension=.gif&FileName=Weather%20Study%20Report%20-%20Attachment%201-Master.gif - Weather Study Report - Attachment 2 (item 3, .GIF, 11.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469457&FileExtension=.gif&FileName=Weather%20Study%20Report%20-%20Attachment%202-Master.gif - Weather Study Report - Attachment 3 (item 4, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469458&FileExtension=.PDF&FileName=Weather%20Study%20Report%20-%20Attachment%203-Master.PDF - Weather Study Report - Attachment 4 (item 5, .PDF, 468 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469459&FileExtension=.PDF&FileName=Weather%20Study%20Report%20-%20Attachment%204-Master.PDF - Weather Study Report - Attachment 5 (item 6, .PDF, 162 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469460&FileExtension=.PDF&FileName=Weather%20Study%20Report%20-%20Attachment%205-Master.PDF - Wreckage Diagram (item 7, .PDF, 1 photo, 373 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469461&FileExtension=.PDF&FileName=Wreckage%20Diagram-Master.PDF - NTSB Accident Site Examination Summary (item 8, .PDF, 65 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469462&FileExtension=.PDF&FileName=NTSB%20Accident%20Site%20Examination%20Summary-Master.PDF - Department of the Navy - Mishap Package (Transcript) (item 9, .PDF, 642 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469463&FileExtension=.PDF&FileName=Department%20of%20the%20Navy%20-%20Mishap%20Package%20(Transcript)-Master.PDF - Video - Radar Track on Sectional (item 10, MP4, 6.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469464&FileExtension=mp4&FileName=Video%20-%20Radar%20Track%20on%20Sectional-Master - CMI Engine Field Report (item 11, .PDF, 7.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469465&FileExtension=.PDF&FileName=CMI%20Engine%20Field%20Report-Master.PDF - Statement of Party Representatives to NTSB Investigation - Textron (item 12, .PDF, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469466&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation%20-%20Textron-Master.PDF - Statement of Party Representatives to NTSB Investigation - CM (item 13, .PDF, 130 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469467&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation%20-%20CM-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 14, .PDF, 155 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469468&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Master.PDF - Toxicological Report (item 15, .PDF, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469469&FileExtension=.PDF&FileName=Toxicological%20Report-Master.PDF - Photo Array (item 16, .PDF, 5 photos, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469470&FileExtension=.PDF&FileName=Photo%20Array-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.