# NTSB CHI97LA178: Grumman-Schweizer G-164A, N48FS, Benton, MO, June 20, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 20, 1997, 15:15 local (20:15 UTC) - Place: Benton, MO - Coordinates: 37.089916, -89.559333 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.0899&lon=-89.5593&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 31, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 10605 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI97LA178 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10605/pdf - Page: https://openairdocs.org/ntsb/CHI97LA178 ## Probable cause the pilot's inadequate preflight by failing to insure that the secondary flight control lock was stowed properly, and subsequently the secondary flight control lock becoming engaged during the takeoff run. A factor relating to the accident was: inadequate design of the secondary flight control lock that was installed by the airplane's owner/pilot. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, takeoff - roll/run - aircraft preflight - inadequate, pilot in command (cause) - flight control,gust lock - engaged (cause) - acft/equip,inadequate design, owner/pilot mechanic (contributing factor) - flight control,aileron - locked - flight control,elevator - locked - Nose over, takeoff - aborted ## Analysis The pilot was departing to the south from the mid-point of a private dirt strip. The airplane accelerated normally. Just after the pilot brought up the tail of the airplane, he realized that a control lock was hung up on the control stick. The pilot could not pull the stick back. He said that he 'throttled back too late. The propeller struck the ground. The airplane did a somersault, landing on its back.' Examination of the wreckage revealed that a secondary ground control lock (installed by the pilot/owner of the airplane) was hooked on the control stick, making it impossible to move the airplane's ailerons or elevator. No other anomalies were found with the airplane. ## Factual narrative On June 20, 1997, at 1515 central daylight time (cdt), a Grumman- Schweizer G-164A, N48FS, operated by a commercial pilot, sustained substantial damage when during its takeoff run the flight controls locked up. During the subsequent abort, the airplane nosed over. Visual meteorological conditions prevailed at the time of the accident. The aerial application flight was being conducted under 14 CFR Part 137. No flight plan was on file. The pilot reported no injuries. The local flight was originating from a private airstrip 5 miles northeast of Benton, Missouri, when the accident occurred. In his written statement, the pilot said that he was departing to the south from the mid-point of a private dirt strip. The airplane accelerated normally. Just after the pilot moved the stick full forward to lift the tail wheel off of the ground, he realized that the control lock was hung up on the control stick. The pilot could not pull back on the stick. The pilot said that he "throttled back too late. The propeller struck the ground. The airplane did a somersault, landing on its back." A Federal Aviation Administration (FAA) inspector examined the wreckage at the site. The airplane's empennage was broken downward and aft. The upper half of the airplane's vertical stabilizer and top half of the rudder were crushed downward. The top surfaces of the upper wings were bent and wrinkled. The forward leading edges of the lower wings were crushed downward and aft. The forward main spar and ribs near the wing roots were bent aft. The propeller exhibited torsional bending, chordwise scratching and tip curling. The engine was restarted and ran normally. A secondary ground control lock was found hooked onto the pin of the control stick making it impossible to move the airplane's ailerons or elevator. No other anomalies were found with the airplane. The airplane manufacturer stated that the control lock which is manufactured for the airplane consists of a "Y-shaped" bar which comes up from under the airplane's control panel with a small tab affixed to it. The tab has 3/8 inch hole in it. The hole fits over a pin mounted on the upper front side of the control stick. The manufacturer's control lock is designed to lock all of the airplane's flight controls. The secondary control lock found hooked on the control stick was installed by the pilot/owner of the airplane. It consisted of a small tab of metal with a 3/8 inch hole in it, mounted to a metal "A-frame" brace on the center floor of the cockpit. It was designed to lock the airplane's ailerons and elevator, leaving the rudder and tailwheel free to move. This allowed for better ground handling of the airplane. ## Aircraft - Registration: [N48FS](https://openairdocs.org/deregistered/N48FS-2000-10-25), registration cancelled 2000-10-25, S/N 1660 (OpenAirDocs) - Reported make and model: Grumman-Schweizer G-164A - Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs) - Category: Airplane - Serial number: 1660 - Airframe hours: 3975 - Engines: P&W R-1340-AN-1 450 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Cecil Beeson - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, June 13, 1997 - Airport: Private Strip, runway 18, 2,600 × 50 ft, dirt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 17,000 total, 15,500 in this make and model, 100 in the last 90 days, 10 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 90 °F ## 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 19970620047339A](https://openairdocs.org/incident/19970620047339A), Jun 20, 1997: Scwzer G164A, Benton, MO, Substantial damage. (-16) While pilot had stick full forward during early part of the takeoff roll as the tail came off the ground the pilot said a secondary gust lock, (that had… ## Other investigations on N48FS (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 CHI98LA114](https://openairdocs.org/ntsb/CHI98LA114), Apr 4, 1998: Grumman G-164A (N48FS), Benton, MO, destroyed. Probable cause: an engine fire for undetermined reasons. 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.