# NTSB CEN15LA235: Lathrop Steven A B8M, N5606X, Ravenna, MI, May 1, 2015 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 1, 2015, 12:25 local (17:25 UTC) - Place: Ravenna, MI - Coordinates: 43.179882, -85.93917 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.1799&lon=-85.9392&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report September 11, 2018 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA FSDO - NTSB case key (mKey): 91193 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN15LA235 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/91193/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=91193 - Page: https://openairdocs.org/ntsb/CEN15LA235 ## Probable cause A total loss of engine power due to carburetor icing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Lathrop Steven A B8M, 1 case](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=059030U), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Lathrop Steven A B8M, 1 case](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=059030U), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Contributed to outcome (probable cause); cases with it: [Lathrop Steven A B8M, 1 case](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=059030U), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Lathrop Steven A B8M, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=059030U), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Lathrop Steven A B8M, 1 case](https://openairdocs.org/ntsb-events/120/sequence.md?model=059030U), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis The private pilot of the gyrocopter stated that, after reducing engine power to descend, the engine experienced a total loss of power due to carburetor ice and that there was nowhere to land. The gyrocopter subsequently impacted 30-ft high power lines and the ground. Examination of the wreckage showed that the rotor blades were coned upward consistent with low rotor rpm at ground impact. Given the weather conditions in the area about the time of the accident, the aircraft would have been operating in conditions conducive to moderate carburetor icing at cruise power and serious icing at descent power. Thus, it is likely that the engine lost power due to carburetor icing. ## Factual narrative On May 1, 2015, about 1225 central daylight time, a homebuilt gyrocopter, N5606X, registered to the pilot/owner, was destroyed when it collided with power lines after a loss of engine power while maneuvering in the vicinity of Ravenna, Michigan. The private pilot, who was the sole occupant, sustained serious injuries. Visual meteorological conditions prevailed in the vicinity and a flight plan was not filed. The local flight was being conducted under the provisions of Federal Code of Regulations Part 91. The flight originated from Riverview, Michigan, about 1125. One witness reported that she heard a loud noise of a plane flying north. She further stated that she heard a loud booming sound and she looked up and saw black smoke. Another witness reported that he received a call from the pilot stating that he would be doing a slow fly-by in the area, about noon. The witness stated that he was outside several minutes after noon and that he heard the gyrocopter flying toward his home, looked up to the southeast, and saw the aircraft gliding toward the ground. The FAA inspector who examined the accident site and wreckage, reported that the wreckage was resting in a deep ditch on the north side of Sherman Road near the intersection of Wunsch Road in Moorland Township near Ravenna, MI. Evidence at the accident site showed that the gyrocopter had impacted 30-foot high power lines, consequently breaking two of the lines. A power line pole on the north side of Sherman Road was broken and unattached to its base. The pilot's headgear showed thermal damage to the face shield and soot was evident inside of the shield and around the face relief of the helmet, consistent with electrical arcing. The helmet was found in a ditch just west of Wunsch Road about 40 feet from the wreckage. The gyrocopter's rotor mast was broken off, about seat height. The rotor blades were coned upward consistent with low RPM and high loading. The trailing edges of the blades exhibited buckling between fasteners. One rotor blade had scuff marks on the bottom side. The other blade had buckling failure in the aft direction. One of the propeller blades of the pusher propeller was separated and was found about 50 yards beyond the wreckage. The broken blade leading edge exhibited leading edge marks consistent with contact with the broken power line wires. The Volkswagen engine appeared to be mostly intact. The crank would rotate by hand, but was limited due to adjacent impact damage. Automotive gasoline was present in the fuel filter and some gas was dripping out of the carburetor when first responders arrived. The broken ends of the power lines showed some broom straw signatures, some cut failures, and some right angle bending near the wire failures. The wires consisted of five aluminum wires wrapped about a steel core. The pilot stated on NTSB Form 6120 that as he slowed the engine to lower his altitude, he "got carb ice killing the engine [and] ran out of a place to land." The nearestweather reporting facility, located about 12 miles to the west of the accident site, reported a temperature of 16 degrees C and dew point of 4 degrees C, about 30 minutes prior to the accident. According to the Carburetor Icing Probability Chart, the aircraft would have been operating in conditions for moderate icing at cruise power and serious icing at descent power. ## Aircraft - Registration: [N5606X](https://openairdocs.org/deregistered/N5606X-2015-11-05), registration cancelled 2015-11-05, S/N 2, built 2007 (OpenAirDocs) - Reported make and model: LATHROP STEVEN A B8M (NO SERIES) - Registry model: [Lathrop Steven A B8M](https://openairdocs.org/model/lathrop-steven-a-b8m) (registry code 059030U) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Gyroplane, amateur-built - Serial number: 2 - Year built: 2008 - Airframe hours: 400 - Engines: Volkswagon 65 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, March 10, 2015, 3 hours before - Departed: Riverview, MI - Destination: MKG, Ravenna, MI - Airport: MKG, Muskegon County Airport - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: serious; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; seat: center; restraint: 3-point; flight hours: 500 total, 100 in this make and model, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 340° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 39 °F - Altimeter: 30.14 inHg - Observed at: MKG, 12 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 20150501006339A](https://openairdocs.org/incident/20150501006339A), May 1, 2015: Lathrop Steven A B8M, Ravenna, MI, Destroyed. Pilot struck powerlines while flying low over farm area. Rotor blade mast severed by powerline contact. Pilot was struck in face and helmet by powerlines.… ## Docket (7 files) The files NTSB released with the investigation on June 13, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=91193. 11.4 MB in all. - NTSB Form 6120 CEN15LA235 (item 1, .PDF, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463941&FileExtension=.PDF&FileName=NTSB%20Form%206120%20CEN15LA235-Master.PDF - Memorandum for the Record Summaries of Witness Statements provided by the Michigan State Police CEN15LA235 (item 2, .PDF, 141 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463942&FileExtension=.PDF&FileName=Memorandum%20for%20the%20Record%20Summaries%20of%20Witness%20Statements%20provided%20by%20the%20Michigan%20State%20Police%20CEN15LA235-Master.PDF - Memorandum for the Record FAA Inspector Accident Site Information CEN15LA235 (item 3, .PDF, 165 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463943&FileExtension=.PDF&FileName=Memorandum%20for%20the%20Record%20FAA%20Inspector%20Accident%20Site%20Information%20CEN15LA235-Master.PDF - Michigan State Police Accident Report CEN15LA235 (item 4, .PDF, 437 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463944&FileExtension=.PDF&FileName=Michigan%20State%20Police%20Accident%20Report%20CEN15LA235-Master.PDF - Weather Information CEN15LA235 (item 5, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463945&FileExtension=.PDF&FileName=Weather%20Information%20CEN15LA235-Master.PDF - Carburetor Icing Probability Chart (item 6, .PDF, 260 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463946&FileExtension=.PDF&FileName=Carburetor%20Icing%20Probability%20Chart-Master.PDF - Photo Array CEN15LA235 (item 7, .PDF, 7.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40463947&FileExtension=.PDF&FileName=Photo%20Array%20CEN15LA235-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.