# NTSB ERA10LA421: Cessna 172R, N2435X, Key West, FL, August 14, 2010 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: August 13, 2010, 21:10 local (Aug 14, 2010, 01:10 UTC) - Place: Key West, FL - Coordinates: 24.553611, -81.755554 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=24.5536&lon=-81.7556&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Loss of visual reference](https://openairdocs.org/ntsb-events/402) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report April 7, 2011 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA South Florida FSDO - NTSB case key (mKey): 76962 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA10LA421 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76962/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76962 - Page: https://openairdocs.org/ntsb/ERA10LA421 ## Probable cause The non-instrument-rated pilot's spatial disorientation during night, over-water, low-ambient-light conditions, which resulted in the airplane impacting the ocean. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Light condition: dark](https://openairdocs.org/ntsb-findings/03036020): Environmental issues › Conditions/weather/phenomena · Contributed to outcome; cases with it: [Cessna 172R, 3 cases](https://openairdocs.org/ntsb-findings/03036020/cases.md?model=2072401), [All aircraft, 448 cases](https://openairdocs.org/ntsb-findings/03036020/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot; cases with it: [Cessna 172R, 75 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2072401), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained; cases with it: [Cessna 172R, 3 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=2072401), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Perception/orientation/illusion: spatial disorientation](https://openairdocs.org/ntsb-findings/02022025): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Cessna 172R, 1 case](https://openairdocs.org/ntsb-findings/02022025/cases.md?model=2072401), [All aircraft, 358 cases](https://openairdocs.org/ntsb-findings/02022025/cases.md) - [Terrain: water](https://openairdocs.org/ntsb-findings/03021020): Environmental issues › Physical environment · Not specified; cases with it: [Cessna 172R, 1 case](https://openairdocs.org/ntsb-findings/03021020/cases.md?model=2072401), [All aircraft, 97 cases](https://openairdocs.org/ntsb-findings/03021020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Loss of visual reference](https://openairdocs.org/ntsb-events/402) (defining event); cases with it: [Cessna 172R, 2 cases](https://openairdocs.org/ntsb-events/402/sequence.md?model=2072401), [All aircraft, 242 cases](https://openairdocs.org/ntsb-events/402/sequence.md) ## Analysis The non-instrument rated pilot performed a touch-and-go practice takeoff and landing at an airport located on an island at night. Thereafter, the flight continued over water at a low altitude. A pilot of a commercial flight inbound to the island observed the accident airplane on his traffic collision and avoidance system (TCAS) and additionally noticed the reflection of its landing light on the water. When the reflection disappeared, the TCAS contact also disappeared, likely due to the airplane impacting the water. After rescue, the pilot could not recall much of the event, but did remark that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation. At the time of the accident, the moon's phase was waxing crescent with 18 percent of the disk illuminated. Federal Aviation Administration Advisory 60-4A states that, "The attitude of an aircraft is generally determined by reference to the natural horizon or other references on the surface. If neither horizon nor surface references exist, the attitude of an aircraft must be determined by artificial means from the flight instruments. ...Spatial disorientation to a pilot means simply the inability to tell which way is up....Lack of natural horizon or surface reference is common on over water flights, at night, and especially at night in extremely sparsely populated areas, or in low visibility conditions." ## Factual narrative On August 13, 2010, at 2110 eastern daylight time, a Cessna 172R, N2435X, registered to Island City Flying Service, Inc., collided with the Atlantic Ocean while maneuvering in a traffic pattern at Key West International Airport (EYW), Key West, Florida. Night visual meteorological conditions prevailed, and no flight plan was filed. The airplane incurred substantial damage, and the certificated, non-instrument-rated private pilot sustained serious injuries. The local personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. According to the first officer (FO) of an American Eagle flight that was inbound for landing at EYW, he and the captain overheard the accident pilot advise Navy Key West Approach Control that he would be conducting touch-and-go landings at EYW. After the subsequently switching to the EYE advisory frequency, the FO contacted the pilot over the radio. The pilot informed him that he had departed runway 9, that he was upwind at 200 feet, south bound, and that he would stay out of their way. The FO informed the pilot that they would be in front of him for landing. The pilot then stated that he was turning to the east and the FO observed the airplane on the traffic collision and avoidance system (TCAS). The FO also observed the landing light come on as the airplane started the turn. The landing light was reflecting off the water, and the FO asked the pilot if that was him. The pilot replied "yes" in a calm voice. About 10 seconds after the light came on, the landing light went out and the flight was no longer showing on TCAS. Further attempts by the FO to contact the pilot were unsuccessful. The pilot stated in an interview from a trauma center that he did not remember talking to the American Eagle flight or the collision with the Atlantic Ocean. He only remembered "bits and pieces" after the accident, and trying to remain afloat until he was rescued. The pilot did not report any mechanical malfunctions, and according to the owner of the airplane, the pilot related to him that "the engine did not quit." Review of the sun and moon data obtained from the U.S. Naval Observatory revealed that the moon's phase was "waxing crescent" with 18 percent of the disk illuminated. The FO, who flew both his own, as well as the accident airplane from EYW, wrote in a statement that there was very little moonlight and "a turn to the south with no light on the horizon can cause severe vertigo and disorientation." Federal Aviation Administration Advisory Circular 60-4A states, "The attitude of an aircraft is generally determined by reference to the natural horizon or other references on the surface. If neither horizon nor surface reference exists, the attitude of an aircraft must be determined by artificial means from the flight instruments. ...Spatial disorientation to a pilot means simply the inability to tell which way is up....Lack of natural horizon or surface reference is common on over water flights, at night,and especially at night in extremely sparsely populated areas, or in low visibility conditions". The wreckage was not recovered and search efforts were terminated by the insurance company. The pilot reported that his logbooks were in the airplane. ## Aircraft - Registration: [N2435X](https://openairdocs.org/deregistered/N2435X-2010-11-15), registration cancelled 2010-11-15, S/N 17280837, built 2000 (OpenAirDocs) - Reported make and model: CESSNA 172R - Registry model: [Cessna 172R](https://openairdocs.org/model/cessna-172r) (registry code 2072401) (OpenAirDocs) - Registry engine: [Lycoming I0360 SER A&C](https://openairdocs.org/engine/lycoming-i0360-ser-a-c) (registry code 41511, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17280837 - Airframe hours: 4832 - Engines: LYCOMING I0360-L2A 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Edgar H. Hinkle Jr. - Registered owner: Island City Flying Service Inc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, March 16, 2010, 40 hours before - Departed: EYW, Key West, FL - Destination: EYW, Key West, FL ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: serious; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; flight hours: 600 total ## Weather - Conditions: Visual (VMC), Night/dark - Wind: 50° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 88 °F, dew point 77 °F - Altimeter: 29.94 inHg - Observed at: EYW ## 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 20100813048309A](https://openairdocs.org/incident/20100813048309A), Aug 13, 2010: Cessna 172R, Key West, FL, Destroyed. On August 13, 2010 at 2115, N2435X a Cessna 172R registered to island city flying service , incorporated operating under 14 CFR part 91 impacted the water… ## Docket (8 files) The files NTSB released with the investigation on January 2, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76962. 788 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 351 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336134&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Statement (item 2, .PDF, 37 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336128&FileExtension=.PDF&FileName=Pilot%20Statement-Redacted.PDF - Statement President Island City Flying Service (item 3, .PDF, 32 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336126&FileExtension=.PDF&FileName=Statement%20President%20Island%20City%20Flying%20Service-Redacted.PDF - American Eagle First Officer Statement (item 4, .PDF, 59 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40335404&FileExtension=.PDF&FileName=American%20Eagle%20First%20Officer%20Statement-Redacted.PDF - Insurance Company E Mail (item 5, .PDF, 43 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40335406&FileExtension=.PDF&FileName=Insurance%20Company%20E%20Mail-Redacted.PDF - US Naval Observatory Sun and Moon Data (item 6, .PDF, 21 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40335407&FileExtension=.PDF&FileName=US%20Naval%20Observatory%20Sun%20and%20Moon%20Data-Master.PDF - Spatial Disorientation 60 4 (item 7, .PDF, 82 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40335408&FileExtension=.PDF&FileName=Spatial%20Disorientation%2060%204-Master.PDF - Extract Airplane Log books (item 8, .PDF, 162 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336135&FileExtension=.PDF&FileName=Extract%20Airplane%20Log%20books-Redacted.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.