# NTSB WPR16LA119: Beech C23, N6697Y, Waianae, HI, May 23, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: May 23, 2016, 11:37 local (21:37 UTC) - Place: Waianae, HI - Coordinates: 21.463611, -158.21527 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=21.4636&lon=-158.2153&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report May 25, 2017 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - SAIBs cited in the narratives: [SAIB CE-09-35](https://openairdocs.org/saib/CE-09-35) (OpenAirDocs) - NTSB case key (mKey): 93269 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR16LA119 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93269/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93269 - Page: https://openairdocs.org/ntsb/WPR16LA119 ## Probable cause The total loss of engine power during cruise flight due to carburetor icing. Contributing to the accident was the pilot’s delay in applying carburetor heat during flight while operating in an area conducive to carburetor icing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause); cases with it: [Beech C23, 3 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=1151242), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Beech C23, 5 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=1151242), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Beech C23, 4 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=1151242), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Beech C23, 7 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=1151242), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Enroute-cruise: Fuel related](https://openairdocs.org/ntsb-events/190); cases with it: [Beech C23, 3 cases](https://openairdocs.org/ntsb-events/190/sequence.md?model=1151242), [All aircraft, 361 cases](https://openairdocs.org/ntsb-events/190/sequence.md) - [Enroute-cruise: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Beech C23, 5 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=1151242), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Enroute-cruise: Ditching](https://openairdocs.org/ntsb-events/441); cases with it: [Beech C23, 1 case](https://openairdocs.org/ntsb-events/441/sequence.md?model=1151242), [All aircraft, 186 cases](https://openairdocs.org/ntsb-events/441/sequence.md) ## Analysis The private pilot reported that, during the climb-to-cruise portion of the cross-country interisland flight over open ocean water, the engine began to run roughly. The pilot applied carburetor heat, which resolved the engine roughness. The pilot decided to continue his flight. As the flight approached his destination, the engine began running roughly again, accompanied by a significant loss of engine rpm. The pilot applied carburetor heat and adjusted the mixture, but the engine power was not restored. He then ditched the airplane into the water just offshore of the island. The airplane wreckage was recovered from the water 3 days after the accident, and it had sustained significant damage from tidal forces. Postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Weather conditions in the area at the time of the accident were conducive to the formation of carburetor icing at glide and cruise power and serious carburetor icing at glide power. If the pilot had either kept the carburetor heat on or applied it earlier, the loss of engine power and subsequent ditching could have been avoided. ## Factual narrative On May 23, 2016, about 1137 Hawaiian standard time, A Beech C23, N6697Y, sustained substantial damage following a loss of engine power and subsequent ditching within the open waters of the Pacific Ocean near Waianae, Hawaii. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and his passenger sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The cross-country flight originated from the Lihue Airport, Lihue, Hawaii, about 20 minutes prior to the accident, with an intended destination of Kalaeloa Airport, Kapolei, Hawaii.The pilot reported that during the climb to cruise portion of the flight, the engine began to run rough. The pilot applied carburetor heat, which resolved the roughness, and he continued his climb to 5,500 feet mean sea level. As the flight was approaching the shores of Oahu Island, the engine began running rough in addition to a reduction of engine rpm to about 1,700. The pilot applied carburetor heat and adjusted the mixture, however, was unsuccessful at restoring engine power. The pilot initiated a forced landing into the ocean waters just off shore of the island of Oahu. The airplane came to rest nose low partially submerged within about 20 feet of water, about 50 to 75 feet from the shoreline. Initial examination of the wreckage revealed that the forward portion of the fuselage was damaged. The wreckage was recovered from the water three days after the accident. Following removal from the water, the engine was rinsed with fresh water and subsequently filled with diesel fuel in an attempt to preserve the engine. Examination of the recovered airplane on June 30, 2016, revealed that it was mostly fragmented into multiple pieces from the ocean tidal action. The engine remained attached to the firewall structure. Corrosion was observed throughout the engine and firewall. The carburetor was separated from its mounts. The magnetos and fuel pump remained secured to their mounting pads. The bottom spark plugs were removed and exhibited corrosion and debris consistent with ocean water and salt. The magnetos were removed. Partial rotational continuity was obtained when the propeller was rotated about ¼ of a turn and mechanical continuity was obtained at the rear of the engine. The right magneto drive shaft rotated however did not produce spark at the lead terminals. Disassembly of the magneto was not performed due to the corrosion on the cap bolts. The left magneto drive shaft would not rotate by hand. Disassembly of the magneto was not performed due to the corrosion on the cap bolts. The carburetor was removed and disassembled for inspection. The internal float was intact and the needle valve was intact. A significant amount of salt and other ocean vegetation debris was observed throughout the float bowl and screen. The right side exhaust remained partially attached tocylinders one and three. No nuts were observed on the cylinder number one exhaust mount and only one nut remained attached to the cylinder number three cylinder exhaust mount. It could not be determined if the missing nuts were displaced prior to the accident or during salvage and subsequent engine preservation methods. No evidence of any preexisting anomalies that would have precluded normal operation and production of power was observed. The Federal Aviation Administration (FAA) published Special Airworthiness Information Bulletin (SAIB) CE-09-35 on June 30, 2009, regarding carburetor ice prevention. The conditions encountered in this accident (ambient temperature 84 degrees F, dew point 63 degrees F) were in the area of icing at glide and cruise power, and in the area of serious icing at glide power. ## Aircraft - Registration: [N6697Y](https://openairdocs.org/deregistered/N6697Y-2016-08-25), registration cancelled 2016-08-25, S/N M-2224, built 1979 (OpenAirDocs) - Reported make and model: BEECH C23 (NO SERIES) - Registry model: [Beech C23](https://openairdocs.org/model/beech-c23) (registry code 1151242) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: M-2224 - Year built: 1979 - Airframe hours: 648.7 - Engines: LYCOMING O&VO-360 SER reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 24, 2016 - Departed: Lihue, HI - Destination: JRF, Kapolei, HI - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 56; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review March 15, 2016; seat: left; restraint: 3-point; flight hours: 224 total, 92 in this make and model, 161 as pilot in command, 3 in the last 90 days, 3 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 3 knots - Visibility: 10 statute miles - Lowest ceiling: 4,500 ft broken - Temperature: 84 °F, dew point 63 °F - Altimeter: 30.12 inHg - Observed at: PHJR, 12 nm away ## Docket (5 files) The files NTSB released with the investigation on April 6, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93269. 2.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450789&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation - Pilot (item 2, .PDF, 55 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450790&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Pilot-Master.PDF - NTSB Airframe and Engine Examination Summary Report (item 3, .PDF, 57 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450791&FileExtension=.PDF&FileName=NTSB%20Airframe%20and%20Engine%20Examination%20Summary%20Report-Master.PDF - FAA Special Airworthiness Bulletin CE-09-35 (item 4, .PDF, 112 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450792&FileExtension=.PDF&FileName=FAA%20Special%20Airworthiness%20Bulletin%20CE-09-35-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 5, .PDF, 118 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450793&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.