# NTSB ERA16LA247: Mormile Francis W Aventura II, N932MC, West Pittsfield, ME, July 9, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: July 9, 2016, 14:53 local (18:53 UTC) - Place: West Pittsfield, ME - Coordinates: 44.694652, -69.382057 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.6947&lon=-69.3821&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern final: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report July 23, 2019 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 93577 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16LA247 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93577/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93577 - Page: https://openairdocs.org/ntsb/ERA16LA247 ## Probable cause The pilot's failure to maintain airplane control after a total loss of engine power due to carburetor icing, which accumulated because the carburetor heat was not functioning. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=056256R), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=056256R), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) - [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: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=056256R), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Power plant](https://openairdocs.org/ntsb-findings/01057100): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/01057100/cases.md?model=056256R), [All aircraft, 198 cases](https://openairdocs.org/ntsb-findings/01057100/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=056256R), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md) - [Power plant: air intake](https://openairdocs.org/ntsb-findings/01057160): Aircraft › Aircraft power plant · Not installed/available; cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-findings/01057160/cases.md?model=056256R), [All aircraft, 50 cases](https://openairdocs.org/ntsb-findings/01057160/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern final: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=056256R), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Approach-VFR pattern final: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=056256R), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Approach-VFR pattern final: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Mormile Francis W AVENTURA II, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=056256R), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The airline transport pilot departed in his amateur-built airplane and planned to stay in the airport traffic pattern to conduct a functional test of the retractable landing gear. He stated that, as he was turning the airplane left to the final leg of the airport traffic pattern, he noticed that the controls were "very stiff" when he tried to roll the airplane level and needed two hands to move the control wheel. The airplane then began to descend. The pilot was unable to level the airplane, and during the continued descent, it collided with trees. After the accident, two witnesses told the pilot that the engine had stopped producing power before the airplane impacted the trees; however, the pilot said he was unaware that the engine had lost power. Postaccident examination of the flight controls revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. Postaccident examination of the engine revealed that the engine exhaust was positioned too close to fuel lines, which did not have heat shielding protection, and that a mandatory fuel return line was not installed, both of which could result in vapor lock to the engine. However, when the engine was test-run, it ran continuously for several minutes without hesitation. Given the successful engine test-run, it is unlikely that vapor lock caused the loss of engine power. Despite the noted deficiencies with the engine's installation, no preimpact mechanical functions or failures of the engine's powertrain were found that would have precluded normal operation. Examination of the airplane also revealed that the carburetor heat was not functional. Given that the atmospheric conditions at the time of the accident were conducive to carburetor icing at glide engine power settings, the carburetor likely accumulated ice. If the engine lost total power due to the accumulation of carburetor ice and the pilot inadvertently allowed the airplane to slow, then the effectiveness of the airplane's flight controls would have been degraded and likely would have resulted in the loss of airplane control, as reported by the pilot. Therefore, it is likely that the carburetor accumulated ice because the carburetor heat was not functioning, which led to the total loss of engine power. ## Factual narrative A review of the engine maintenance logbooks revealed the fuel pump was installed new in 2015 per Rotax Service Bulletin SB-912-063: Replacement of fuel pumps for ROTAX Engine type 912 (series). The SB was issued in March 2013 and the replacement of the pump was only "Recommended". According to a representative of Rotax, when the new fuel pump was installed, a mandatory fuel return line should have been installed to prevent vapor lock. The fuel return line was made mandatory via an amendment to the Rotax 912 Series Engine Installation Manual (EIM) on August 1, 2012. No other notifications were issued. However, further review of SB 912-063 revealed there was no guidance or reference that the return fuel line was mandatory. It only stated that the person installing the new fuel pump should use the Illustrated Parts Catalog and Heavy Maintenance Manual (HMM) for guidance. Neither of those manuals stated the fuel return line was mandatory. A review of the FAA's Carburetor Icing Probability Chart revealed that atmospheric conditions were conducive to serious icing at glide power. The airplane was originally built in 2008 and then sold to the pilot in January 2015, when it was still in Phase I testing for an FAA special, experimental airworthiness certificate. The pilot made an entry in the aircraft maintenance logbook on June 24, 2016, that Phase I testing was completed and had moved into Phase II testing. A review of the engine maintenance logbook revealed the Rotax 912ULS engine was installed new on the airplane on April 8, 2008. The pilot reported the engine had accrued a total of about 35 hours at the time of the accident. The airframe had accrued about 44 hours total time. On July 9, 2016, about 1453 eastern daylight time, an experimental amateur-built Aventura II airplane, N932MC, was substantially damaged when it impacted terrain while on approach to Grignons Private Landing Area (ME62) in West Pittsfield, Maine. The airline transport pilot sustained minor injuries. The airplane was registered to and operated by the pilot. Visual meteorological conditions prevailed for the personal flight conducted under the provisions of 14 Code of Federal Regulations Part 91. No flight plan was filed for the flight that departed ME62 about 1450. The pilot stated that the purpose of the flight was to perform a functional test of the retractable landing gear. He said he started the engine and taxied for about 10 minutes before he departed. The takeoff was normal and the pilot made a left turn to stay in the airport traffic pattern and climbed to an altitude of about 200 ft. The pilot said that when he was making the turn toward the final approach leg of the traffic pattern, he noticed the controls were very stiff when he tried to roll level. He needed two hands to move the control wheel. The pilot also noticed that he was descending and was unable to avoid trees off the side of the runway. The airplane struck the trees and impacted the ground in a nose-downattitude. Two witnesses told the pilot that the engine stopped producing power prior to the airplane impacting the trees. The pilot said he was wearing a full-size helmet and was unaware that the engine had lost power and was focused on trying to level the airplane. Weather reported at Bangor International Airport (BGR), Bangor, Maine, about 23 miles west of the accident site, at 1453, was wind 130 at 5 knots, visibility 10 miles, overcast clouds at 1800 ft, temperature 18° C, dewpoint 12° C, and a barometric pressure setting 29.96 inches Hg. The pilot held an airline transport pilot certificate with ratings for airplane single and multiengine land and single-engine sea. In addition, he held ratings for balloon and rotorcraft-helicopter and an instrument rating for airplane and rotorcraft-helicopter. The pilot also held a flight instructor certificate with ratings for airplane single and multiengine. He reported a total of 6,763 total flight hours, of which, 44 hours were in the accident airplane. His last Federal Aviation Administration (FAA) first class medical was issued on November 20, 2015. Postaccident examination of the airplane revealed that it sustained substantial damage to the fuselage and both wings. Flight control continuity was confirmed from the control surfaces to the cockpit controls. The engine remained attached to the airframe and all three propeller blades remained attached to the propeller hub. The engine and blades sustained minimal impact damage. The airplane was not equipped electronic device to record engine performance. A postaccident examination of the engine revealed the fuel system consisted of a fuel pump that was equipped with two carburetors, both of which were removed and disassembled. Each float bowl was empty of fuel and a small amount of corrosion was noted underneath the floats in each bowl. Both carburetors were then reinstalled back on the engine. Examination of the fuel lines revealed that a fuel pressure indicator was installed but it was not connected electrically. The gascolator bowl was removed and examined. The bowl was about half full of fuel that was absent of debris and water. The oil pump, oil filter, oil cooler and the oil tank appeared undamaged. That oil tank was filled with the proper amount of oil needed to safely operate the engine. The exhaust system was an after-market installation (non-Rotax). The exhaust, which included four exhaust pipes and a muffler, were mounted above the engine near temperature sensitive components and fuel lines. No heat shielding was installed to protect these components from radiant heat. According to Rotax's Engine Installation manual (EIM), "To avoid vapor lock keep the temperature of the fuel lines, float chamber and related devices below 113F (45C)." The electronic ignition modules were also found near the exhaust and have a maximum temperature of 176° F. The induction system, which consisted of an optional AirBox, air filter, and carburetor heat, revealedthe linkage that allowed the pilot to switch from filtered air to carburetor heat was not connected. The lever was positioned so induction air was being pulled from the carburetor heat side of the AirBox (non-filtered air). The carburetor heat was not operational. The air filter was grey in color and was not coated with the protective "red" oil that kept dirt particles from entering the engine. The spark plugs were removed and no anomalies were noted. The engine's crankshaft was rotated and continuity and compression were established on each cylinder via manual rotation of the propeller. The engine was prepped to be test run, which involved using a car battery with battery cables to boost the airplane's battery. After several attempts, the engine started and ran at idle for several minutes before the throttle was advanced to a higher power setting. The engine ran continuously at this higher setting for several minutes without hesitation. No mechanical deficiencies were noted that would have precluded normal operation of the engine. ## Aircraft - Registration: [N932MC](https://openairdocs.org/deregistered/N932MC-2018-06-08), registration cancelled 2018-06-08, S/N AA2AO138, built 2008 (OpenAirDocs) - Reported make and model: MORMILE FRANCIS W AVENTURA II (NO SERIES) - Registry model: [Mormile Francis W AVENTURA II](https://openairdocs.org/model/mormile-francis-w-aventura-ii) (registry code 056256R) (OpenAirDocs) - Registry engine: [Rotax 912ULS series](https://openairdocs.org/engine/rotax-912uls-series) (registry code 55572, 4 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: AA2AO138 - Airframe hours: 44 - Engines: Rotax 912 ULS 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, September 1, 2015 - Departed: ME62, West Pittsfield, ME - Destination: ME62, West Pittsfield, ME - Airport: ME62, Grignons Field, runway 35, 2,500 × 75 ft, grass/turf - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; injuries: minor; airline transport, commercial, private, flight instructor; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review December 5, 2015; seat: left; restraint: 4-point; flight hours: 6,763 total, 44 in this make and model, 2,836 as pilot in command, 105 in the last 90 days, 50 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 1,800 ft overcast - Temperature: 64 °F, dew point 54 °F - Altimeter: 29.95 inHg - Observed at: BGR, 23 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 20160709010889A](https://openairdocs.org/incident/20160709010889A), Jul 9, 2016: Mormile Francis W AVENTURA II, Pittsfield, ME, Substantial damage. The pilot took off from a private field and had gotten to an altitude of approximately 200FT. He made a turn to the left to head back to the airport and when… ## Docket (6 files) The files NTSB released with the investigation on February 27, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93577. 9.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470615&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Airframe Logbook Information (item 2, .PDF, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470616&FileExtension=.PDF&FileName=Airframe%20Logbook%20Information-Master.PDF - Engine Logbook Information (item 3, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470617&FileExtension=.PDF&FileName=Engine%20Logbook%20Information-Master.PDF - Summary of Record - FAA (item 4, .PDF, 100 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470618&FileExtension=.PDF&FileName=Summary%20of%20Record%20-%20FAA-Master.PDF - Rotech Flight Safety Factual Report (item 5, .PDF, 2.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470619&FileExtension=.PDF&FileName=Rotech%20Flight%20Safety%20Factual%20Report-Master.PDF - FAA Carburetor Icing Probability Chart (item 6, .PDF, 218 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40470620&FileExtension=.PDF&FileName=FAA%20Carburetor%20Icing%20Probability%20Chart-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.