# NTSB CEN14LA118: Grumman American Avn. AA 5B, N28578, Willow Park, TX, January 21, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 21, 2014, 15:00 local (21:00 UTC) - Place: Willow Park, TX - Coordinates: 32.750785, -97.770935 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.7508&lon=-97.7709&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 15, 2014 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA -- North Texas Flight Standards - NTSB case key (mKey): 88703 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14LA118 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/88703/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=88703 - Page: https://openairdocs.org/ntsb/CEN14LA118 ## Probable cause The improper reinstallation of the propeller assembly, which resulted in the subsequent in-flight separation of the propeller. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Propeller system: propeller hub section](https://openairdocs.org/ntsb-findings/01046114): Aircraft › Aircraft propeller/rotor · Failure (probable cause); cases with it: [Grumman American Avn. AA-5B, 1 case](https://openairdocs.org/ntsb-findings/01046114/cases.md?model=3960105), [All aircraft, 13 cases](https://openairdocs.org/ntsb-findings/01046114/cases.md) - [Propeller system: propeller assembly](https://openairdocs.org/ntsb-findings/01046110): Aircraft › Aircraft propeller/rotor · Incorrect service/maintenance (probable cause); cases with it: [Grumman American Avn. AA-5B, 1 case](https://openairdocs.org/ntsb-findings/01046110/cases.md?model=3960105), [All aircraft, 29 cases](https://openairdocs.org/ntsb-findings/01046110/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) (defining event); cases with it: [Grumman American Avn. AA-5B, 2 cases](https://openairdocs.org/ntsb-events/338/sequence.md?model=3960105), [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Grumman American Avn. AA-5B, 7 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=3960105), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Grumman American Avn. AA-5B, 10 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3960105), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Grumman American Avn. AA-5B, 2 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=3960105), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot reported that he heard a loud noise during cruise flight and that the airplane then started losing altitude. He subsequently conducted a forced landing, which resulted in substantial damage to the airplane. A postaccident examination revealed that the propeller assembly had separated from the engine propeller flange. Four of the six propeller bolts were intact, consistent with the bolts backing out before the propeller separated. The remaining two bolts were unable to transfer the loads from the propeller, and they subsequently failed. The pilot reported that the propeller was removed during the most recent annual inspection, which was completed about 1 year before the accident. The airplane had accumulated about 14 hours flight time since the inspection. Although the airplane maintenance logbook entry for the inspection did not indicate that the propeller was removed or reinstalled, it is likely that the propeller assembly was improperly reinstalled at some point, which resulted in its subsequent in-flight separation. ## Factual narrative On January 21, 2014, about 1500 central standard time, a Grumman American AA-5B airplane, N28578, was substantially damaged during a forced landing following an in-flight separation of the propeller near Willow Park, Texas. The pilot was not injured. The airplane was substantially damaged. The airplane was registered to a private individual and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was not operated on a flight plan. The local flight originated from the Lake Whitney State Park Airport (F50), Whitney, Texas, about 1445. The pilot reported that he heard a loud noise during cruise flight at 2,000 feet mean sea level. He was unable to maintain altitude and subsequently executed a forced landing to the infield of a horse racing track. The airplane encountered a drainage ditch during the landing, which caused the nose and right main landing gears to collapse. A postaccident examination revealed that the two-blade, fixed-pitch propeller assembly had separated from the engine propeller flange. The propeller was recovered about three days later from a pasture located about 8 miles east-southeast of the accident site. The propeller bolts, which were retained by the spinner, were recovered. Four of the bolts were intact, with no apparent damage to either the bolt threads or the propeller flange insert threads. The remaining two bolts had failed with the threaded portion of the bolt retained by the propeller flange insert. The appearance of portions of the fracture surfaces appeared consistent with fatigue failure. Safety wire remnants were recovered with the bolts. Airplane maintenance records indicated that an annual inspection was completed on January 14, 2013. The airframe and engine had accumulated about 32,055 hours total time, with about 14 hours since the annual inspection. The engine had accumulated about 412 hours since overhaul. The pilot informed Federal Aviation Administration inspectors that the propeller assembly had been removed and reinstalled during the most recent annual inspection. However, the maintenance logbook entry did not include a notation regarding the removal of the propeller. ## Aircraft - Registration: [N28578](https://openairdocs.org/deregistered/N28578-2016-11-16), registration cancelled 2016-11-16, S/N AA5B0693, built 1978 (OpenAirDocs) - Reported make and model: GRUMMAN AMERICAN AVN. CORP. AA 5B - Registry model: [Grumman American Avn. AA-5B](https://openairdocs.org/model/grumman-american-avn-aa-5b) (registry code 3960105) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: AA5B0693 - Year built: 1978 - Airframe hours: 32055 - Engines: LYCOMING O-360-A4K 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Jack E Barnett - Registered owner: Terry L Melton - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 14, 2014, 14 hours before - Departed: F50, Whitney, TX - Destination: F50, Whitney, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 79; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review October 24, 2012; seat: left; flight hours: 711 total, 711 in this make and model, 711 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 52 °F, dew point 18 °F - Altimeter: 30.29 inHg - Observed at: MWL, 21 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 20140121000659A](https://openairdocs.org/incident/20140121000659A), Jan 21, 2014: Grumman American Avn. Corp. AA-5B, Willow Park, TX, Substantial damage. On January 21, 2014, at approximately 1520 central daylight time, a Grumman AA-5B tiger, N25878, departed bourland field in cresson Texas and proceeded north… ## Docket (8 files) The files NTSB released with the investigation on October 3, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=88703. 6.6 MB in all. - Pilot/Operator Aircraft Accident Report (item 1, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417313&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report-Redacted.PDF - Pilot Logbook – Excerpts (item 2, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417314&FileExtension=.PDF&FileName=Pilot%20Logbook%20%E2%80%93%20Excerpts-Redacted.PDF - Aircraft Maintenance Logbook – Excerpts (item 3, .PDF, 885 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417315&FileExtension=.PDF&FileName=Aircraft%20Maintenance%20Logbook%20%E2%80%93%20Excerpts-Redacted.PDF - Engine Maintenance Logbook – Excerpts (item 4, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417316&FileExtension=.PDF&FileName=Engine%20Maintenance%20Logbook%20%E2%80%93%20Excerpts-Redacted.PDF - Photo 1 – Accident Site (item 5, .PDF, 266 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417317&FileExtension=.PDF&FileName=Photo%201%20%E2%80%93%20Accident%20Site-Master.PDF - Photo 2 – Propeller and Spinner (item 6, .PDF, 179 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417318&FileExtension=.PDF&FileName=Photo%202%20%E2%80%93%20Propeller%20and%20Spinner-Master.PDF - Photo 3 – Propeller Flange (item 7, .PDF, 567 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417319&FileExtension=.PDF&FileName=Photo%203%20%E2%80%93%20Propeller%20Flange-Master.PDF - Photo 4 – Propeller Bolts (item 8, .PDF, 612 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40417320&FileExtension=.PDF&FileName=Photo%204%20%E2%80%93%20Propeller%20Bolts-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.