# NTSB WPR14LA180: Bell 47G, N7895B, El Monte, CA, May 3, 2014 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: May 3, 2014, 09:15 local (16:15 UTC) - Place: El Monte, CA - Coordinates: 34.085834, -118.034721 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.0858&lon=-118.0347&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report November 30, 2015 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 89156 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR14LA180 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/89156/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=89156 - Page: https://openairdocs.org/ntsb/WPR14LA180 ## Probable cause A partial loss of engine power during climbout due to a malfunctioning magneto and spark plugs. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Ignition system: magneto/distributor](https://openairdocs.org/ntsb-findings/01057414): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Bell 47G, 1 case](https://openairdocs.org/ntsb-findings/01057414/cases.md?model=1181002), [All aircraft, 101 cases](https://openairdocs.org/ntsb-findings/01057414/cases.md) - [Ignition system: spark plugs/igniters](https://openairdocs.org/ntsb-findings/01057421): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Bell 47G, 1 case](https://openairdocs.org/ntsb-findings/01057421/cases.md?model=1181002), [All aircraft, 38 cases](https://openairdocs.org/ntsb-findings/01057421/cases.md) - [Terrain](https://openairdocs.org/ntsb-findings/03021000): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Bell 47G, 1 case](https://openairdocs.org/ntsb-findings/03021000/cases.md?model=1181002), [All aircraft, 267 cases](https://openairdocs.org/ntsb-findings/03021000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Bell 47G, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=1181002), [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: [Bell 47G, 3 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=1181002), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Dynamic rollover](https://openairdocs.org/ntsb-events/231); cases with it: [Bell 47G, 3 cases](https://openairdocs.org/ntsb-events/231/sequence.md?model=1181002), [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) ## Analysis The pilot reported that, during climbout, the engine experienced a partial loss of power, the helicopter shook violently, and the engine then made a couple of "popping" sounds. He immediately initiated a precautionary landing to an open field. During the landing, the right skid caught on the ground, and the helicopter then rolled onto its right side. During postaccident functional tests, the left magneto and the No. 5 cylinder's spark plugs did not function properly. No further evidence of mechanical malfunctions or failures that would have precluded normal operation were observed. Therefore, it is likely that the malfunctioning left magneto and spark plugs caused the partial loss of engine power. ## Factual narrative On May 3, 2014, about 0915 Pacific daylight time, a Bell 47G, N7895B, sustained substantial damage during a precautionary landing, about 3 miles south of the El Monte Airport (EMT) El Monte, California. The helicopter was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and passenger sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The cross-country flight originated at EMT about 0910, with a destination of Compton/Woodley Airport, Compton, California. The pilot reported that during climb out, about 600-700 feet above ground level, the engine experienced a partial loss of power. The pilot stated the helicopter shook violently and the engine made a couple of popping sounds. He immediately initiated a precautionary landing at an open field. The pilot stated that during the landing, he carried a little forward speed and the right skid caught on the ground and rolled the helicopter on to its right side. Examination of the helicopter by the pilot revealed that the fuselage and main rotor blades were structurally damaged. The wreckage was recovered to a local storage facility for further examination. Examination of the recovered airframe and engine was accomplished by a certified airframe and powerplant (A&P) mechanic, under the supervision of the National Transportation Safety Board investigator-in-charge. The examination revealed that the engine remained attached through all of its mounts. The carburetor was intact and disassembled. All internal components of the carburetor were intact. The top spark plugs were removed and the engine was rotated by hand. Thumb compression was obtained on all cylinders and proper valve movement was observed. All engine control continuity with the cockpit controls was established. Both of the magnetos were intact and removed in order to functionally test them on a test bench. During the test sequence, the right magneto functioned normally; producing a spark at all leads during various rpm settings. The left magneto was tested and did not function properly. At low rpm setting, spark was not observed at the leads. At higher rpm settings, spark was observed at the leads but was intermittent and firing at random. The left magneto was disassembled and the internal rotor was observed loose from its attachment. The spark plugs were removed to be functionally checked on a spark plug tester. All the spark plugs functioned normally with the exception of the number 5 cylinder's spark plugs. The top spark plug had heavy carbon deposits in the electrode area and no spark was observed. The lower spark plug electrode area had corrosion present and the electrode was thermally damaged. Review of the helicopter's maintenance records revealed that the engine and airframe underwent their most recent annual inspection on August 28, 2013, at an engine total time of 537 hours and airframetime of 2,726 hours. ## Aircraft - Registration: [N7895B](https://openairdocs.org/deregistered/N7895B-2017-10-20), registration cancelled 2017-10-20, S/N 1706, built 1958 (OpenAirDocs) - Reported make and model: BELL 47G (UNDESIGNAT) - Registry model: [Bell 47G](https://openairdocs.org/model/bell-47g) (registry code 1181002) (OpenAirDocs) - Registry engine: [Franklin 6V4 series](https://openairdocs.org/engine/franklin-6v4-series) (registry code 27033, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 1706 - Year built: 1958 - Airframe hours: 2726 - Engines: FRANKLIN 6V4 SERIES 235 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 28, 2013 - Departed: EMT, EL MONTE, CA - Destination: CPM, Compton, CA, CA - Airport: EMT, El Monte ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review September 15, 2014; seat: left; restraint: lap only; flight hours: 1,882 total, 682 in this make and model, 15.8 in the last 90 days, 4.8 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 100° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 36 °F - Altimeter: 29.90 inHg - Observed at: CQT, 10 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 20140503013909A](https://openairdocs.org/incident/20140503013909A), May 3, 2014: Bell 47G, Whittier, CA, Substantial damage. On may 3, 2014, civil aircraft N7598B, a Bell 47G helicopter, departed san gabriel valley airport (EMT) at 1618UTC for a flight to compton woodley airport… ## Other investigations on N7895B (2) 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 CHI73DEI14](https://openairdocs.org/ntsb/CHI73DEI14), Aug 27, 1972: Bell 47G (N7895B), Oregon, OH, substantial damage - [NTSB NYC68A0014](https://openairdocs.org/ntsb/NYC68A0014-201123), Jul 21, 1967: Bell 47G (N7895B), Wayland, NY, substantial damage ## Docket (3 files) The files NTSB released with the investigation on November 3, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=89156. 7.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 7.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40433434&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 2, .PDF, 34 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40433435&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Master.PDF - Helicopter Examination Report (item 3, .PDF, 163 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40433436&FileExtension=.PDF&FileName=Helicopter%20Examination%20Report-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.