# NTSB ERA10LA396: Cessna 177B, N925KM, Mashpee, MA, August 2, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 2, 2010, 12:05 local (16:05 UTC) - Place: Mashpee, MA - Coordinates: 41.549999, -70.483329 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.5500&lon=-70.4833&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: No injuries - Injuries: 2 uninjured - Status: Completed, report June 13, 2011 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - SAIBs cited in the narratives: [SAIB CE-09-35](https://openairdocs.org/saib/CE-09-35) (OpenAirDocs) - NTSB case key (mKey): 76846 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA10LA396 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76846/pdf - Page: https://openairdocs.org/ntsb/ERA10LA396 ## Probable cause The pilot’s delayed use of carburetor heat while flying at reduced power settings in conditions that were favorable for carburetor icing resulting in the partial loss of engine power. ## 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 · Contributed to outcome; cases with it: [Cessna 177B, 2 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=2073708), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Info processing/decision: understanding/comprehension](https://openairdocs.org/ntsb-findings/02041515): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Cessna 177B, 1 case](https://openairdocs.org/ntsb-findings/02041515/cases.md?model=2073708), [All aircraft, 70 cases](https://openairdocs.org/ntsb-findings/02041515/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: [Cessna 177B, 5 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2073708), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Ditching](https://openairdocs.org/ntsb-events/441); cases with it: [Cessna 177B, 1 case](https://openairdocs.org/ntsb-events/441/sequence.md?model=2073708), [All aircraft, 186 cases](https://openairdocs.org/ntsb-events/441/sequence.md) ## Analysis The flight had been flown at a reduced power setting and about 2 hours and 5 minutes into it, the pilot moved the propeller control to the low pitch position and applied the carburetor heat. The engine lost power and in response, the pilot removed the carburetor heat and then attempted to restore engine power by reapplying carburetor heat and switching the fuel selector to another tank. The engine only responded for a few seconds and lost power again. He maneuvered the airplane for a forced landing and ditched near a shoreline. A postaccident examination of the engine and engine accessories by a Federal Aviation Administration inspector revealed no evidence of mechanical failures or malfunctions that could have contributed to the loss of engine power. Based on the temperature and dew point about the time of the accident, the conditions were favorable for serious icing at glide power. ## Factual narrative On August 2, 2010, about 1205 eastern daylight time, a Cessna 177B, N925KM, registered to Rocky Wings, Inc., sustained substantial damage while ditching after a loss of engine power near the southern coastline of Mashpee, Massachusetts. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight conducted under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The private pilot and one passenger were not injured. The flight originated from Fairmouth Airpark, Fairmouth, Massachusetts, about 1000. The pilot stated that he conducted a thorough preflight inspection and engine run-up before departure, with no discrepancies noted. The flight departed with full fuel tanks and flew locally at 1,000 feet with the power set to 20 inches manifold pressure and 2,300 rpm for most of the flight. While south of Mashpee, preparing to return to the departure airpark, the pilot moved the propeller control to the low pitch position and applied carburetor heat, but the engine lost power. He immediately removed carburetor heat which did not restore engine power, and trimmed to maintain 70 knots while attempting to restore engine power by the application of carburetor heat, and switching the fuel selector to the left and right positions. The engine responded for a few seconds then lost power again. The pilot then concentrated his efforts at flying the airplane and elected to ditch the airplane away from the beach area. The airplane remained upright after water contact and both occupants exited from the co-pilot's door and swam to shore. Examination of the engine by a Federal Aviation Administration (FAA) airworthiness inspector revealed crankshaft, camshaft, and valve train continuity. Inspection of the ignition system components consisting of the magnetos, spark plugs, and ignition leads revealed no evidence of preaccident failures or malfunctions. Inspection of the air induction and exhaust systems revealed some impact damage but there was no evidence of preaccident failures or malfunctions. Inspection of the oil filter revealed no ferrous contamination, and the fuel system components consisting of the carburetor, engine-driven fuel pump, auxiliary fuel pump and flexible fuel lines revealed no evidence of preaccident failures or malfunctions. No mechanical reasons for the reported loss of engine power could be determined. Review of FAA Special Airworthiness Information Bulletin CE-09-35, titled Carburetor Icing Prevention revealed that, based on the temperature and dew point about the time of the accident, 75 and 52 degrees Fahrenheit respectively, the atmospheric conditions were favorable for serious icing at glide power. ## Aircraft - Registration: [N925KM](https://openairdocs.org/deregistered/N925KM-2017-06-30), registration cancelled 2017-06-30, S/N 17702316, built 1975 (OpenAirDocs) - Reported make and model: CESSNA 177B - Registry model: [Cessna 177B](https://openairdocs.org/model/cessna-177b) (registry code 2073708) (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: 17702316 - Airframe hours: 2944 - Engines: LYCOMING O-360-A1F6 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Rocky Wings Inc - Registered owner: Rocky Wings Inc - Airworthiness certificate: Standard, Normal; Standard, Utility - Last inspection: Annual, April 1, 2010, 10 hours before - Departed: 5B6, Falmouth, MA - Destination: 5B6, Falmouth, MA - Airport: 5B6, Falmouth Airpark ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 64; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review September 17, 2008; seat: left; flight hours: 306 total, 159 in this make and model, 223 as pilot in command, 10 in the last 90 days, 4 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 52 °F - Altimeter: 30.17 inHg - Observed at: FMH, 7 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 20100802041219A](https://openairdocs.org/incident/20100802041219A), Aug 2, 2010: Cessna 177B, Falmouth, MA, Substantial damage. Pilot operated aircraft in VMC conditions conducive to induction icing for approximately 1-1/2 hours. As pilot was preparing for final approach to Falmouth… 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.