# NTSB WPR15LA003: Corben Baby Ace D, N3RH, Lincoln, CA, October 5, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 5, 2014, 12:15 local (19:15 UTC) - Place: Lincoln, CA - Coordinates: 38.880001, -121.340835 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.8800&lon=-121.3408&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report February 23, 2015 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 90219 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR15LA003 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90219/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90219 - Page: https://openairdocs.org/ntsb/WPR15LA003 ## Probable cause The total loss of engine power due to fuel starvation, which resulted from debris restricting the fuel flow within the fuel system. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fuel system: fuel filter-strainer](https://openairdocs.org/ntsb-findings/01022821): Aircraft › Aircraft systems · Capability exceeded (probable cause); cases with it: [Corben Baby Ace D, 1 case](https://openairdocs.org/ntsb-findings/01022821/cases.md?model=00301TX), [All aircraft, 52 cases](https://openairdocs.org/ntsb-findings/01022821/cases.md) - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Corben Baby Ace D, 1 case](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=00301TX), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Corben Baby Ace D, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=00301TX), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing-landing roll: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Corben Baby Ace D, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=00301TX), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) (defining event); cases with it: [Corben Baby Ace D, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=00301TX), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis Following an uneventful takeoff and straight-out departure, the pilot leveled the airplane about 1,000 ft above ground level, at which point, the engine began to sputter, and it subsequently lost power. The pilot initiated a return to the departure airport; however, due to the low altitude, he initiated a forced landing to a nearby field. During the landing, the main landing gear collapsed, and the airplane nosed over. Postaccident examination of the airplane revealed that the gascolator screen and fuel outlet port were partially restricted with red, sandlike debris, which would have restricted the fuel flow to the carburetor and led to the loss of engine power. ## Factual narrative On October 5, 2014, about 1215 Pacific daylight time, an experimental amateur built Corben Baby Ace, N3RH, was substantially damaged during a forced landing shortly after takeoff from the Lincoln Regional Airport (LHM), Lincoln, California. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot, sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The local flight originated from LHM about 5 minutes prior to the accident.In a written statement to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), the pilot reported that he departed runway 15 and flew straight out to about 1,000 feet above ground level (agl) when the engine began to sputter. The pilot stated that he initiated a 180-degree turn toward the airport, however, did not have enough altitude to make the airport and initiated a forced landing to a nearby field. During the off-airport landing, the landing gear collapsed and the airplane subsequently nosed over. Examination of the airplane by the NTSB IIC revealed that the fuselage and engine firewall was structurally damaged. The airplane was recovered to a secure location for further examination. Examination of the recovered airplane revealed that the wings were removed to facilitate recovery of the airplane. The Continental C75-12 engine, serial number 179612, remained attached to the airframe. All engine accessories remained attached with the exception of the carburetor, which was displaced from its mounts. The top spark plugs were removed and the crankshaft was rotated by hand using the propeller. Thumb compression was obtained on all four cylinders. Both magnetos produced spark with impulse coupling engagement when the crankshaft was rotated. The carburetor was intact, however, separated from its mounts. The throttle and mixture levers moved from stop to stop when the levers were actuated. When the throttle lever was actuated, the accelerator pump expelled fuel. The carburetor was disassembled and examined. The internal float bowl contained residual liquid that was consistent with automotive fuel. A small amount of red sand like debris was observed within the float bowl. The carburetor fuel screen was found to be free of debris. The floats and needle valve assembly were unremarkable. The airframe fuel strainer (gascolator) was found intact with all of the fuel lines secure. The gascolator bowl was removed and some red sand like debris was noted. The screen was removed and a significant amount of red sand like debris was observed partially restricting the screen and fuel outlet port to the engine. The source of the debris was not determined. Review of the airframe and engine logbooks revealed that the most recent condition inspection was completed on August 8, 2014. The mechanic who performed the condition inspection reported thathe removed the gascolator screen and found no debris during the inspection. The pilot reported to the NTSB IIC that the airplane had been in storage for several years and that he had flushed the fuel tank multiple times to remove any debris that may have gathered. He further stated that at the time of the accident, the airplane had about 6 hours of flight time since the inspection. ## Aircraft - Registration: [N3RH](https://openairdocs.org/aircraft/N3RH), registered now, S/N REH-1 (OpenAirDocs) - Reported make and model: CORBEN BABY ACE D (UNDESIGNAT) - Registry model: [Corben Baby Ace D](https://openairdocs.org/model/corben-baby-ace-d) (registry code 00301TX) (OpenAirDocs) - Registry engine: [Continental A&C75 series](https://openairdocs.org/engine/continental-a-c75-series) (registry code 17005, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: REH-1 - Year built: 1972 - Airframe hours: 484 - Engines: Continental C75 75 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Knobloch Elmer W - Registered owner: Knobloch Elmer W - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, September 8, 2014, 6 hours before - Departed: LHM, Lincoln, CA - Destination: LHM, Lincoln, CA - Airport: LHM, Lincoln Rgnl/Karl Harder Field ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 64; injuries: none; private; airplane ratings: single-engine land; medical: sport pilot; last flight review June 10, 2013; seat: center; restraint: 3-point; flight hours: 1,487 total, 11 in this make and model, 1,487 as pilot in command, 6 in the last 90 days, 6 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 41 °F - Altimeter: 29.95 inHg - Observed at: KSMF, 16 nm away ## Other investigations on N3RH (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 OAK78DVA50](https://openairdocs.org/ntsb/OAK78DVA50), Jun 27, 1978: Corben Baby A (N3RH), Modesto, CA, substantial damage ## Docket (5 files) The files NTSB released with the investigation on November 21, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90219. 10.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 5.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419324&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Conversation (Pilot) (item 2, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419325&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(Pilot)-Master.PDF - Record of Conversation (Mechanic) (item 3, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419326&FileExtension=.PDF&FileName=Record%20of%20Conversation%20(Mechanic)-Master.PDF - Photo 1 – View of the gascolator and debris. (item 4, .PDF, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419327&FileExtension=.PDF&FileName=Photo%201%20%E2%80%93%20View%20of%20the%20gascolator%20and%20debris.-Master.PDF - Photo 2 – View of the carburetor float bowl and debris. (item 5, .PDF, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40419328&FileExtension=.PDF&FileName=Photo%202%20%E2%80%93%20View%20of%20the%20carburetor%20float%20bowl%20and%20debris.%0D%0A-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.