# NTSB ERA18FA230: Aeronca 7AC, N65HM, Hanson, MA, August 24, 2018 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: August 24, 2018, 15:35 local (19:35 UTC) - Place: Hanson, MA - Coordinates: 42.022499, -70.835281 - Nearby events: https://openairdocs.org/map.md?lat=42.0225&lon=-70.8353&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Fatal - Injuries: 1 fatal, 1 serious - Status: Completed, report April 20, 2020 - 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): 98152 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA18FA230 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/98152/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=98152 - Page: https://openairdocs.org/ntsb/ERA18FA230 ## Probable cause A loss of engine power due to carburetor icing, the pilot's decision to turn back to the runway shortly after takeoff, and his failure to maintain airspeed during the turn, which resulted in an exceedance of the airplane's critical angle of attack, and subsequent aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Aeronca 7AC, 9 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=2110102), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Aeronca 7AC, 43 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2110102), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Aeronca 7AC, 7 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=2110102), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Aeronca 7AC, 10 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=2110102), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/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: [Aeronca 7AC, 5 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=2110102), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Contributed to outcome (probable cause); cases with it: [Aeronca 7AC, 5 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=2110102), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Standing: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Aeronca 7AC, 4 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=2110102), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Aeronca 7AC, 10 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=2110102), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Aeronca 7AC, 44 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2110102), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The commercial pilot and passenger were departing on a local personal flight in the single-engine airplane. Review of airport security video showed the airplane level off about 100 ft above ground level as it passed the departure end of the runway. The airplane then entered a left turn and descended to ground contact. Damage to the propeller blades was consistent with a lack of engine power at the time of impact; however, examination of the wreckage revealed no evidence of preimpact mechanical anomalies that would have prevented normal engine operation. Based on the temperature and dew point about the time of the accident, the conditions were favorable for serious carburetor icing at a glide power setting. Video showed that the airplane operated on the ground at an idle engine power setting for about 7 minutes before takeoff, and it is probable that carburetor ice formed during this time, subsequently resulting in the loss of engine power during the initial climb. Following the loss of power, the pilot attempted to turn back to the runway with insufficient altitude and, during the turn, failed to maintain airspeed, resulting in an exceedance of the airplane's critical angle of attack, an aerodynamic stall/spin, and impact with terrain. ## Factual narrative FAA Special Airworthiness Information Bulletin (CE-09-35) – Carburetor Icing Prevention, stated that: …pilots should be aware that carburetor icing doesn't just occur in freezing conditions, it can occur at temperatures well above freezing temperatures when there is visible moisture or high humidity. Icing can occur in the carburetor at temperatures above freezing because vaporization of fuel, combined with the expansion of air as it flows through the carburetor, (Venturi Effect) causes sudden cooling, sometimes by a significant amount within a fraction of a second. Carburetor ice can be detected by a drop in rpm in fixed pitch propeller airplanes and a drop in manifold pressure in constant speed propeller airplanes. In both types, usually there will be a roughness in engine operation. According to FAA records, the airplane was manufactured in 1946. It was equipped with a Continental Motors Inc. C90 series, 90-horsepower engine that drove a fixed-pitch propeller. According to airplane maintenance logbooks, an annual inspection was completed on October 1, 2017, at a total time of 1,521.4 hours and a tachometer time of 3,215.1 hours. Following the accident, the tachometer indicated 3,325.1 hours. The airplane was flown the day before the accident by the owner's son and the accident pilot. The owner's son reported that there were no anomalies with the airplane during their flight, which lasted about an hour. He stated that he usually applied carburetor heat while operating the engine at idle power on the ground because of the "carburetor icing possibilities." The engine operating instructions stated that, during the pretakeoff ground test (engine run-up), the carburetor heat control should be moved "to full HOT position, and observe decrease in engine speed if air heater and control are operating properly. [Then] return control to full COLD position." The instructions noted, "under some conditions, ice may form in the carburetor during ground test. It must be eliminated before takeoff." Cranland Airport was a public, nontower-controlled airport located 3 miles southeast of Hanson, Massachusetts. The airport was equipped with an asphalt runway designated as 18/36, which was 1,760 ft long by 60 ft wide. The airport elevation was 71 ft above mean sea level (msl); the airport was surrounded by cranberry bogs, ponds, and wooded terrain. On August 24, 2018, around 1535 eastern daylight time, an Aeronca 7AC Champion, N65HM, was substantially damaged when it impacted terrain shortly after takeoff from Cranland Airport (28M), Hanson, Massachusetts. The commercial pilot was fatally injured and the passenger was seriously injured. The airplane was privately owned and was being operated as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight, which was originating at the time of the accident. A review of airport security video showed the airplane about 100ft above ground level as it passed the departure end of the runway during takeoff. The airplane was not climbing and began to bank to the left; the left turn continued as the airplane descended behind trees and impacted terrain. The video also indicated that the airplane operated at idle engine power on the ground for about 7 minutes before beginning the takeoff roll. First responders reported that the airplane came to rest in a nose-down, near-vertical position and that they had to move the airplane in order to perform rescue operations. The passenger stated to a first responder that the airplane "stalled." The Office of the Medical Examiner, Boston, Massachusetts, performed an autopsy on the pilot. The autopsy report indicated that the cause of death was multiple blunt force injuries. Toxicology testing of the pilot was performed at the FAA Forensic Sciences Laboratory. Fluid and tissue specimens tested negative for ethanol. Ketamine, norketamine, midazolam, lorazepam, and morphine were all detected in the blood and liver. In addition, fentanyl was detected in the blood. All detected medications were consistent with emergency medical treatment after the accident. The 1552 recorded weather observation at Plymouth Municipal Airport (PYM), Plymouth, Massachusetts, about 8 miles southeast of the accident location, included wind from 210° at 9 knots, 10 miles visibility, clear skies, temperature 27°C, dew point 12°C; and an altimeter setting of 30.20 inches of mercury. The carburetor icing probability chart from FAA Special Airworthiness Information Bulletin (SAIB): CE-09-35 Carburetor Icing Prevention, showed a probability of serious icing at glide power at the temperature and dew point reported at the time of the accident. According to Federal Aviation Administration (FAA) records, the pilot held a commercial pilot certificate with ratings for rotorcraft-helicopter, instrument helicopter, and private pilot privileges for airplane single-engine land and sea. The pilot was issued a first-class FAA medical certificate on October 10, 2017, with no limitations. According to the pilot's logbook, he had accumulated 195.7 hours of civilian flight experience, of which 4 hours were in the accident airplane in the previous 3 years. An exemplar airplane with a Continental Motors Inc. C90 engine was started and the fuel selector was moved to the OFF position. The engine operated for 31 seconds before the engine lost total power without sputtering. The airplane was restarted and operated at idle power for about 5 minutes. After that time, the engine was shut down and condensation was noted on the carburetor and intake of the engine. At the time of the test, the ambient temperature was 28°C and the dew point was 15°C, which showed a probability of serious icing at glide power on the Carburetor Icing Probability Chart. The airplane impacted a bog 470 ft east of the departure end of runway 18. The main wreckage was located at an elevation of 59 ft msl. Allcomponents of the airplane were located in the vicinity of the wreckage. The nose section was impact crushed aft. Flight control continuity was confirmed from the flight controls in the cockpit to all flight control surfaces. The carburetor heat control was in the OFF position. The leading edges of the right and left wings were impact crushed along the entire span of each wing. A fuel sample was taken from both fuel tanks and the samples tested negative for water contamination. The empennage and aft flight control surfaces remained intact and attached to the fuselage. The airplane was not equipped with a stall warning system or angle of attack indicator. The engine remained attached to the airframe and the propeller remained attached to the engine. One propeller blade was bent slightly aft and the other blade remained straight. Engine crankshaft continuity was confirmed from the propeller flange to the accessory section. All cylinders remained attached to the crankcase and thumb compression and suction was observed on all cylinders when the propeller was rotated through the entire range of motion. The rocker box covers were removed and no anomalies were noted with the valve springs and rocker arms. Valvetrain continuity was confirmed when the propeller was rotated by hand. The carburetor hot air inlet was impact crushed aft. Carburetor heat control continuity was confirmed from the airbox to the cockpit, and the control was cut to facilitate further examination. The control could not be moved as a result of impact damage. The carburetor was removed and disassembled. The gasket was examined with no anomalies noted. The float assembly remained intact with no anomalies noted. The butterfly valve and fuel pump operated when the throttle arm was moved by hand. The needle and seat remained in place. The carburetor bowl was examined and contained brownish fluid similar to the water in the bog; the fluid smelled similar to 100LL aviation fuel. The left and right magnetos were removed. When each magneto was rotated by hand, spark was observed on all towers. The top spark plugs were removed. The spark plugs were in "normal" condition when compared to the Champion Check a Plug Chart, with the exception of the No. 2 top spark plug, which exhibited "normal-worn out" condition. ## Aircraft - Registration: [N65HM](https://openairdocs.org/deregistered/N65HM-2022-02-05), registration cancelled 2022-02-05, S/N 7AC-3708, built 1946 (OpenAirDocs) - Reported make and model: Aeronca 7AC (No Series) - Registry model: [Aeronca 7AC](https://openairdocs.org/model/aeronca-7ac) (registry code 2110102) (OpenAirDocs) - Registry engine: [Continental A&C65 series](https://openairdocs.org/engine/continental-a-c65-series) (registry code 17003, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 7AC-3708 - Year built: 1946 - Airframe hours: 1631.4 - Engines: Continental Motors Inc. C90-12F 95 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 1, 2017, 110 hours before - Departed: 28M, Hanson, MA - Destination: 28M, Hanson, MA - Airport: 28M, Cranland, runway 18, 1,760 × 60 ft, asphalt - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 33; injuries: fatal; commercial; airplane ratings: single-engine sea, single-engine land; instrument ratings: helicopter; medical: class 1, without waivers/limitations; last flight review April 19, 2016; seat: front; restraint: 3-point; toxicology performed; flight hours: 195 total, 4 in this make and model, 116 as pilot in command, 4.5 in the last 90 days, 4.5 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 54 °F - Altimeter: 30.20 inHg - Observed at: PYM, 8 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 20180824012229A](https://openairdocs.org/incident/20180824012229A), Aug 24, 2018: Aeronca 7AC, Hanson, MA, Destroyed, 1 fatal. On August 24, 2018, N65HM departed runway 18 at the Cranland Airport (28M) around 1500 eastern daylight time. There were no witnesses to the accident so the… ## Other investigations on N65HM (1) 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. - [NTSB CHI07CA258](https://openairdocs.org/ntsb/CHI07CA258), Aug 5, 2007: Aeronca 7AC (N65HM), Westerly, RI, substantial damage. Probable cause: The pilot's failure to maintain control of the airplane during landing which resulted in the overload failure of the right main landing gear. The overload failure of the right main landing gear was a… ## Docket (12 files) The files NTSB released with the investigation on March 17, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=98152. 28.2 MB in all. - Witness Interview Summaries (item 1, .PDF, 183 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481178&FileExtension=.PDF&FileName=Witness%20Interview%20Summaries-Master.PDF - Pilot Logbook (item 2, .PDF, 11.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481179&FileExtension=.PDF&FileName=Pilot%20Logbook-Master.PDF - Maintenance Log Excerpts (item 3, .PDF, 7.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481180&FileExtension=.PDF&FileName=Maintenance%20Log%20Excerpts-Master.PDF - Engine Operating Instructions (item 4, .PDF, 280 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481181&FileExtension=.PDF&FileName=Engine%20Operating%20Instructions-Master.PDF - Weather Observations (item 5, .PDF, 148 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481182&FileExtension=.PDF&FileName=Weather%20Observations-Master.PDF - Carburetor Icing Probability Chart (item 6, .PDF, 723 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481183&FileExtension=.PDF&FileName=Carburetor%20Icing%20Probability%20Chart-Master.PDF - Cranland Airport (28M) and Surrounding Area (item 7, .PDF, 184 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481184&FileExtension=.PDF&FileName=Cranland%20Airport%20(28M)%20and%20Surrounding%20Area-Master.PDF - Investigative Photographs (item 8, .PDF, 7.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481185&FileExtension=.PDF&FileName=Investigative%20Photographs-Master.PDF - Pilot Toxicological Report (item 9, .PDF, 72 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481186&FileExtension=.PDF&FileName=Pilot%20Toxicological%20Report-Master.PDF - Carburetor Icing Potential Testing Information (item 10, .PDF, 234 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481187&FileExtension=.PDF&FileName=Carburetor%20Icing%20Potential%20Testing%20Information-Master.PDF - FAA SAIB - Carburetor Icing Prevention (item 11, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481188&FileExtension=.PDF&FileName=FAA%20SAIB%20-%20Carburetor%20Icing%20Prevention-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 12, .PDF, 144 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40481189&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.