# NTSB WPR11LA233: Palmer RV6A, N52VC, Cody, WY, May 21, 2011 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 21, 2011, 14:50 local (20:50 UTC) - Place: Cody, WY - Coordinates: 44.029998, -109.746948 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.0300&lon=-109.7469&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report November 3, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 79198 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11LA233 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/79198/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=79198 - Page: https://openairdocs.org/ntsb/WPR11LA233 ## Probable cause The pilot’s failure to maintain sufficient altitude to avoid rising terrain. Contributing to the accident was the pilot’s visual illusion and disorientation due to the flat light conditions. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=0561542), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) - [Perception/orientation/illusion: visual illusion/disorientation](https://openairdocs.org/ntsb-findings/02022015): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/02022015/cases.md?model=0561542), [All aircraft, 51 cases](https://openairdocs.org/ntsb-findings/02022015/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=0561542), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Terrain: mountainous/hilly terrain](https://openairdocs.org/ntsb-findings/03021010): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/03021010/cases.md?model=0561542), [All aircraft, 329 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md) - [Terrain: snowy/icy terrain](https://openairdocs.org/ntsb-findings/03021030): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/03021030/cases.md?model=0561542), [All aircraft, 77 cases](https://openairdocs.org/ntsb-findings/03021030/cases.md) - [Light condition: flat light](https://openairdocs.org/ntsb-findings/03036025): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-findings/03036025/cases.md?model=0561542), [All aircraft, 42 cases](https://openairdocs.org/ntsb-findings/03036025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Palmer Joe A RV6A, 1 case](https://openairdocs.org/ntsb-events/120/sequence.md?model=0561542), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis The pilot reported that, when the airplane was at 13,500 feet mean sea level and flying over snow-covered mountainous terrain, he changed course and initiated a descent to avoid moisture-laden clouds. During the descent into a valley, the pilot noticed "slightly rising terrain," so he initiated a climb. The pilot reported that it appeared he had a visual illusion because he thought the airplane was at a higher altitude than the approaching terrain. The airplane subsequently impacted the snow-covered mountain and sustained substantial damage to the fuselage. The passenger stated that he and the pilot had become disoriented. It is likely that the snow-covered terrain and the overcast sky created a flat light condition, which inhibited the visual cues necessary for the pilot to orient himself to the terrain. The pilot reported no preimpact mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Factual narrative On May 21, 2011, about 1450 mountain daylight time, an experimental amateur built Palmer RV6A airplane, N52VC, impacted mountainous terrain in the Teton National Forest near Cody, Wyoming. The pilot/owner operated the airplane under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. The pilot and one passenger received serious injuries. The airplane sustained substantial damage to the fuselage. Visual meteorological conditions prevailed for the flight that departed from Marsing, Idaho, at 1138, and no flight plan had been filed. According to the Federal Aviation Administration (FAA) coordinator, the pilot had Visual Flight Rules (VFR) flight following services with Salt Lake City Center (SLCC) about an hour prior to the accident, when SLCC terminated flight following services due to no radar coverage in the mountains. SLCC personnel had to relay the flight following termination through another pilot. The accident pilot responded affirmatively to the flight following termination, via relay with the other pilot. Before the accident, SLCC relayed to the pilot that there were several pilot reports (PIREPS) for icing between 11,000 feet and 16,500 feet mean sea level (MSL). In the pilot's written statement, he reported that the airplane was at 13,500 feet to clear high terrain in a mountainous area. The pilot changed course and descended from 13,500 feet to avoid clouds that appeared to be "moisture laden." During the descent into a valley, the pilot noticed "slightly rising terrain" and initiated a climb. The pilot stated that it appeared he had a visual illusion, and thought they were at a higher altitude than the upcoming terrain. The airplane subsequently impacted a mound of snow. According to the passenger, they had been flying in a mountainous area, and had become disoriented from the white out conditions. The pilot reported not preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation. The Park County Search and Rescue coordinator stated that, the airplane came to rest upright in 4 feet of snow at an elevation of 10,800 feet. The pilot was able to relay a mayday call through a pilot to Salt Lake City Center. ## Aircraft - Registration: [N52VC](https://openairdocs.org/deregistered/N52VC-2012-11-28), registration cancelled 2012-11-28, S/N 24642, built 2003 (OpenAirDocs) - Reported make and model: PALMER RV6A - Registry model: [Palmer Joe A RV6A](https://openairdocs.org/model/palmer-joe-a-rv6a) (registry code 0561542) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 24642 - Year built: 2003 - Airframe hours: 556 - Engines: LYCOMING O-320 SERIES 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, October 1, 2010, 27 hours before - Departed: ID40, Marsing, ID - Destination: KBYG, Buffalo, WY - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; injuries: serious; flight instructor, airline transport, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review August 27, 2009; seat: left; flight hours: 7,400 total, 130 in this make and model, 7,100 as pilot in command, 10 in the last 90 days, 5 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: 6,000 ft overcast - Temperature: 52 °F, dew point 30 °F - Altimeter: 29.96 inHg - Icing: Unknown - Observed at: KJAC, 50 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 20110521009269A](https://openairdocs.org/incident/20110521009269A), May 21, 2011: Palmer Joe A RV6A, Cody, WY, Minor damage. On 05/21/2011, at 1430 MDT, N52VC, a vans RV-6A amateur-built airplane impacted a mountain valley snow-field at approximately 10,600 feet MSL. The two persons… ## Docket (4 files) The files NTSB released with the investigation on September 26, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=79198. 3.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 554 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416893&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Conversation - Magid (item 2, .PDF, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416894&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Magid-Redacted.PDF - FAA Air Traffic Accident Package (item 3, .PDF, 2.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416895&FileExtension=.PDF&FileName=FAA%20Air%20Traffic%20Accident%20Package-Redacted.PDF - Photo 1 – Accident Site and Surrounding Terrain (Photo Courtesy of Park County Search and Rescue) (item 4, .PDF, 107 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40416896&FileExtension=.PDF&FileName=Photo%201%20%20%E2%80%93%20Accident%20Site%20and%20Surrounding%20Terrain%20(Photo%20Courtesy%20of%20Park%20County%20Search%20and%20Rescue)%0D%0A-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.