# NTSB ERA20LA287: Piper PA34, N41382, Groton, CT, August 18, 2020 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: August 17, 2020, 22:36 local (Aug 18, 2020, 02:36 UTC) - Place: Groton, CT - Coordinates: 41.350833, -72.024169 - Nearby events: https://openairdocs.org/map.md?lat=41.3508&lon=-72.0242&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern base: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 3 minor; on the ground: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: Hartzell Propeller, Piper Aircraft, Inc., FAA/FSDO - NTSB case key (mKey): 101811 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA20LA287 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101811/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101811 - Page: https://openairdocs.org/ntsb/ERA20LA287 ## Probable cause The reported partial loss of right engine power for reasons that could not be determined based on available evidence. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Piper PA-34-200, 2 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=7103405), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/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 base: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Piper PA-34-200, 2 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7103405), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-34-200, 3 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7103405), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-34-200, 10 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7103405), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis During an instructional flight, the pilot receiving instruction performed several landings at several airports before proceeding to the home base airport where he executed two touch-and go landings and remained in the airport traffic pattern. When abeam the approach end of the landing runway while on the downwind leg of the airport traffic pattern with the landing gear extended and 10° of flaps extended, the receiving instruction began to descend while turning onto the base leg of the airport traffic pattern. The flight instructor stated that at time he heard an engine sputter and verified the engine controls were in the proper position. He heard the engine sputter again and "felt the [airplane] jerk" and stated, "my controls." He maintained airspeed and verified the engine controls were full forward, retracted the flaps but decided to leave the landing gear extended due to the altitude and proximity to the airport. He verified the malfunction to be the right engine and felt it was developing some power, but with less output than the left. He briefly pitched nose down, then nose up, and when he noticed a high descent rate, he feathered the right propeller and placed the right mixture control to idle cutoff. He maneuvered for a forced landing on a street but collided with and remained suspended in the roof of a house. Postaccident examination of both engines, their systems, left propeller, and left propeller governor revealed no evidence of preimpact failure or malfunction. There was no evidence or preimpact failure or malfunction of either fuel supply system. While the flight instructor reported he moved the right propeller control to the feather position near the end of the flight, the right propeller blades were on the start locks and not feathered. Functional testing of the right propeller and operational testing of the right propeller governor revealed no preimpact failure or malfunction. Therefore, there was no mechanical reason why the right propeller blades would not feather if commanded before the engine rpm became too low and engaged the propeller start locks. ## Factual narrative On August 17, 2020, about 2236 eastern daylight time, a Piper PA-34-200, N41382, was substantially damaged when it impacted a house near the Groton-New London Airport (GON), Groton, Connecticut. The flight instructor and pilot receiving instruction sustained minor injuries. An occupant of the house was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. According to the flight instructor, they departed GON about 1700 hours and flew direct to Bangor International Airport (BGR), Bangor, Maine, where they landed uneventfully, and the fuel tanks were filled. According to the flight instructor, the flight departed BGR around 2000 then proceeded to Augusta State Airport (AUG), Augusta Maine, (where the pilot receiving instruction performed one touch-and-go landing) then to Portland International Jetport (PWM), Portland, Maine (where the pilot receiving instruction performed three touch-and-go landings). After the last touch-and-go landing, the flight proceeded to GON where the pilot receiving instruction performed two touch-and-go landings to runway 23. The flight departed and remained in the traffic pattern for the same runway, where, when abeam the approach end of runway 23 with the landing gear extended and 10° of flaps extended, the pilot receiving instruction began to descend while turning onto the base leg of the airport traffic pattern. The flight instructor stated that at the time he heard an engine sputter and verified the controls were in the proper position. He heard the engine sputter again, "felt the [airplane] jerk," and took control of the airplane. He maintained airspeed and verified the engine controls were full forward. He retracted the flaps but decided to leave the landing gear extended due to the altitude and proximity to the airport. He verified the malfunction to be the right engine and felt it was developing some power but with less output than the left. He briefly pitched nose down, then nose up, and when he noticed a high descent rate, he moved the right propeller control to the feather position and placed the right mixture control to idle cutoff. He looked for a place to land and maneuvered for landing on a street. While flaring to land, he felt a collision. The airplane came to rest suspended by the roof structure of a house. Examination of the cockpit while the airplane was suspended on the roof was not performed by an Federal Aviation Administration inspector for safety concerns. A photograph of the throttle quadrant taken before the airplane was removed from the house revealed the left throttle control was full forward and the right throttle control was at the aft stop. The left propeller control was about 65% forward travel and the right propeller control was 75% forward travel. The left mixture control was about 60% forward travel, while the right mixture control was at idle cutoff. The left cowl flap was closed while the right cowl flap was open. The leftengine alternate air control was on, while the right engine alternate air control was off. The airplane was recovered for further examination of the airframe, engines and their systems, propellers and propeller governors. Following removal from the house, the FAA inspector reported fuel was present at both fuel strainers and oil was present in each engine. Examination of the airplane following recovery revealed all engine controls for both engines remained attached to their respective attach points at each servo fuel injector and propeller governor. Flight control continuity for the ailerons, elevator, and rudder was confirmed except where the control cables were cut for recovery. The flap handle was in the down/stowed position, consistent with the flaps being retracted. Both auxiliary fuel pump switches were in the on position, and both electrically tested satisfactory. Both fuel tanks of both wings were breached and did not contain any fuel, and neither fuel strainer contained any residual fuel. The left fuel selector was in the ON position and the right fuel selector was in the CROSSFEED position. No obstructions of the fuel supply lines were noted. Both CROSSFEED drains were checked and about 6 ounces of fuel drained from the bottom of the airframe. The fuel odor and viscosity were consistent with 100LL, but the liquid was cloudy and was not tinted blue. Testing detected no water in the fuel sample. Operational testing of each fuel selector revealed no evidence of preimpact failure or malfunction. Examination of the left and right engines and their systems revealed no evidence of preimpact failure or malfunction. Both propeller governors and propellers were examined at the manufacturer’s facility with virtual oversight provided by the National Transportation Safety Board. Examination of the left propeller revealed impact damage that precluded functional testing. Disassembly of the propeller revealed no evidence of preimpact failure or malfunction. The damage to the propeller blades was consistent with the engine not developing high power at impact. Visual examination of the right propeller revealed the blades appeared to be on the start locks. Although the amount of engine oil drained from the right cylinder was not quantified, it was greater than the amount if the propeller was in the feathered position. This was consistent with the propeller blades being in low pitch and that the governor had not dumped the oil to the engine. Following removal of the start lock/feather stop sleeve assembly and when air pressure was removed, both blades moved to the feather position. Cycling of the propeller blades from feather to low pitch was performed several times using shop air with no discrepancies noted. No evidence of preimpact failure or malfunction was noted to the propeller, and the blades exhibited minimal damage consistent with the engine not developing power at impact. The right propeller was not disassembled. Operational testing of the leftpropeller governor revealed several minor out-of-tolerance conditions (such as control lever travel, high rpm setting 40 rpm too low, and relief pressure 1 psi too high). All other checks, including feather check, were within limits. Operational testing of the right propeller governor revealed all checks, including feather check, were within limits. Only one setting (high rpm setting) was 21 rpm too low. Neither propeller governor was disassembled. ## Aircraft - Registration: [N41382](https://openairdocs.org/deregistered/N41382-2024-10-11), registration cancelled 2024-10-11, S/N 34-7450114, built 1974 (OpenAirDocs) - Reported make and model: Piper PA34 (200) - Registry model: [Piper PA-34-200](https://openairdocs.org/model/piper-pa-34-200) (registry code 7103405) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 34-7450114 - Year built: 1974 - Airframe hours: 20641.3 - Engines: Lycoming IO-360-C1E6 200 horsepower reciprocating; Lycoming LIO-360-C1E6 200 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Upgrade Incorporated - Registered owner: Upgrade Incorporated - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, July 9, 2020 - Departed: BGR, Bangor, ME - Destination: GON, Groton, CT - Airport: GON, Groton-New London Airport, runway 23, 5,000 × 150 ft, asphalt - Equipment: Stall warning system, Auto-pilot, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 25; injuries: minor; remote, flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review April 4, 2019; seat: right; restraint: 3-point; flight hours: 1,545 total, 443 in this make and model, 1,393 as pilot in command, 154 in the last 90 days, 22 in the last 30 days - Student pilot; age 23; injuries: minor; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review April 1, 2020; seat: left; restraint: 3-point; flight hours: 10 total ## Weather - Conditions: Visual (VMC), Night - Wind: 220° at 5 knots - Visibility: 10 statute miles - Temperature: 70 °F, dew point 66 °F - Altimeter: 29.87 inHg - Turbulence: Unknown - Observed at: GON, 2 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 20200817013089A](https://openairdocs.org/incident/20200817013089A), Aug 17, 2020: Piper PA-34-200, Groton, CT, Substantial damage. On August 17, 2020 at 2330 hours, local, FAA iic received notice regarding a twin-engine aircraft accident at 243 ring drive, Groton CT 06340 that impacted a… ## Docket (10 files) The files NTSB released with the investigation on September 1, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101811. 16.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11559336&FileExtension=pdf&FileName=NTSB%20Accient%20Report%20Recd%208%2029%202020_Redacted-Rel.pdf - Statement from accident CFI (item 2, PDF, 1 page, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11558608&FileExtension=pdf&FileName=Statement%20From%20CFI_Redacted-Rel.pdf - Statement from pilot undergoing instruction (item 3, PDF, 1 page, 49 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11563626&FileExtension=pdf&FileName=Memorandum%20For%20Record%20-%20Statement%20from%20Pilot%20Undergoing%20Instruction_Redacted-Rel.pdf - Statement from FAA designated pilot examiner (item 4, PDF, 1 page, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11564051&FileExtension=pdf&FileName=Statement%20from%20FAA%20DPE_Redacted-Rel.pdf - Statement from CFI who flew the accident airplane (item 5, PDF, 1 page, 768 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11558646&FileExtension=pdf&FileName=Statement%20From%20CFI%20Who%20Flew%20the%20Accident%20Airplane_Redacted-Rel.pdf - Record of NTSB conversation (item 6, PDF, 5 pages, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11559346&FileExtension=pdf&FileName=Record%20of%20NTSB%20Conversation_Redacted-Rel.pdf - Memorandum for record - aircraft, engines, propeller governors, and propellers examination (item 7, PDF, 1 page, 145 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12495882&FileExtension=pdf&FileName=Memorandum%20For%20Record%20-%20Engine,%20Propeller%20and%20Propeller%20Governor%20Examinations-Rel.pdf - Investigative photographs (item 8, PDF, 5 pages, 5 photos, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12484254&FileExtension=pdf&FileName=Investigative%20Photographs_ERA20LA287-Rel.pdf - Statement of party representatives to NTSB investigation (item 9, PDF, 10 pages, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12184949&FileExtension=pdf&FileName=Party%20Forms%20w%20Attachments_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15, and evidence control forms (item 10, PDF, 5 pages, 3.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12460961&FileExtension=pdf&FileName=Wreckage%20Release%20and%20Evidence%20Control%20Forms_Redacted-Rel.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.