# NTSB ATL95LA004: Aero Commander S2R, N8971Q, Ashburn, GA, October 5, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 5, 1994, 12:00 local (16:00 UTC) - Place: Ashburn, GA - Coordinates: 31.699405, -83.650474 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.6994&lon=-83.6505&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 5, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 3492 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL95LA004 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/3492/pdf - Page: https://openairdocs.org/ntsb/ATL95LA004 ## Probable cause THE FAILURE OF A BLADE COUNTERWEIGHT BEARING SHAFT, ALLOWING ONE PROPELLER BLADE TO GO TO HIGH PITCH. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, maneuvering - aerial application - propeller system/accessories,counterweight - disengaged (cause) - Forced landing, descent - emergency - On ground/water encounter with terrain/water, landing - roll - terrain condition - dirt bank/rising embankment ## Analysis THE COMMERCIAL PILOT HAD COMPLETED SPRAYING OPERATIONS ON A COTTON FIELD. AS HE WAS LEAVING THE AREA, HE BEARD A 'BANG' OR 'PING' SOUND, AUDIBLE ABOVE THE ENGINE NOISE. THE AIRCRAFT BEGAN TO VIBRATE, AND ALTITUDE COULD NOT BE MAINTAINED. HE FORCE LANDED THE AIRCRAFT IN A COTTON FIELD, AND STRUCTURAL DAMAGE RESULTED WHEN THE AIRCRAFT BOGGED DOWN IN THE COTTON PLANTS. A POST- ACCIDENT INSPECTION OF THE PROPELLER REVEALED A BLADE COUNTERWEIGHT BEARING SHAFT HAD FAILED, ALLOWING ONE OF THE BLADES TO GO TO HIGH PITCH. ## Factual narrative On October 5, 1994, at 1200 eastern daylight time, an Aero Commander S2R, N8971Q, was substantially damaged during a forced landing near Ashburn, Georgia. The commercial pilot was not injured. The aircraft was operated under the provisions of 14 CFR Part 137 by Coney Ag Service, of Cordele, Georgia. Visual meteorological conditions prevailed at the time, and no flight plan was filed for the local, aerial application flight. The flight originated in Ashburn at 1115. The pilot reported that he was spraying defoliant chemicals on a cotton field. When he was exiting the field, he heard a loud "bang" or "ping", audible above the engine noise. The aircraft started to vibrate, and would not maintain altitude. The only landing site available was a cotton field. During the forced landing, the aircraft bogged down in the cotton plants, and began to nose over. The left wing contacted the ground, pulling the tail back down, and the aircraft came to a stop. An airworthiness inspector from the Federal Aviation Administration visited the accident site, and inspected the aircraft. His inspection of the propeller revealed that a counterweight bearing shaft failed, allowing one blade to go to high pitch during flight. The propeller logbook could not be located, therefore propeller service and overhaul information could not be determined. ## Aircraft - Registration: [N8971Q](https://openairdocs.org/deregistered/N8971Q-2013-05-17), registration cancelled 2013-05-17, S/N 1641R, built 1972 (OpenAirDocs) - Reported make and model: AERO COMMANDER S2R - Registry model: [Aero Commander S2R](https://openairdocs.org/model/aero-commander-s2r) (registry code 0143022) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1641R - Airframe hours: 1684 - Engines: P&W R-1340-AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Farrow, Sammy N., doing business as Coney Ag Service - Registered owner: Farrow, Sammy N. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, July 2, 1994, 277 hours before - Departed: 75J - Destination: 75J, GA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 2,300 total, 1,000 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 10° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 54 °F - Altimeter: 30.00 inHg - Observed at: ABY, 30 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 19941005034449A](https://openairdocs.org/incident/19941005034449A), Oct 5, 1994: Ayres S2RR1340REST, Ashburn, GA, Substantial damage. Loud bang on pullup from spray run. Engine vibration. Force landed in cotton. Prop counterweight bearing failed. 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.