# NTSB CHI98LA366: Beech BE-35, N8946M, Point Lookout, MO, September 29, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 29, 1998, 16:20 local (21:20 UTC) - Place: Point Lookout, MO - Location: 36.6259° N, 93.2289° W: Placed by OpenAirDocs at M GRAHAM CLARK DOWNTOWN (PLK), within about a mile (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=36.6259&lon=-93.2289&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report March 31, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 45117 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI98LA366 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/45117/pdf - Page: https://openairdocs.org/ntsb/CHI98LA366 ## Probable cause The pilot's continued flight with a known deficiency in equipment. Contributing to the accident was the maintenance adjustment that was not completed by the mechanic. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, climb - mixture control - output low (cause) - maintenance,adjustment - not performed, other maintenance personnel (contributing factor) - operation with known deficiencies in equipment - attempted, pilot in command (contributing factor) - Forced landing, descent - emergency - On ground/water encounter with terrain/water, emergency landing ## Analysis The aircraft impacted terrain, while returning to Runway 29 at M. Graham Clark Airport, Point Lookout, Missouri, after experiencing a partial loss of engine power. The pilot reported that the mechanic, who inspected the mixture control, had replaced the outer mixture control clamps. The pilot also stated that the mechanic recommended to leave the control full rich until a mechanic could troubleshoot the reason that the control linkage allowed the mixture to go over center. The pilot stated that no paperwork was generated on the clamp replacement and that the mechanic did not want to charge for the work. The mechanic stated, that he had replaced a cable housing clamp and rigged the mixture control to the full rich stop. He also told the pilot that it was still not rigged correctly and would take a week to troubleshoot and repair. The mechanic further reported, that he showed the discrepancy to the pilot and told him he could do whatever he wanted to do. Inspection of the aircraft revealed that there was fuel present in both fuel tanks. Both magnetos were tested and no anomalies were noted. Inspection of the mixture control revealed that it was not travelling to the idle cut-off stop and that the full rich stop pin was not in place. ## Factual narrative On September 29, 1998, at 1620 central daylight time, a Beech 35, N8946M, piloted by a private pilot, received substantial damage on impact with terrain while returning to Runway 29 (3,730 feet by 100 feet, asphalt/dry) at M. Graham Clark Airport (PLK), Point Lookout, Missouri. The aircraft experienced a partial loss of engine power. Visual meteorological conditions prevailed at the time of the accident. The pilot and passengers reported no injuries. The 14 CFR Part 91 personal flight was not operating on a flight plan. The flight departed PLK, at 1620, and was en route to Slidell, Louisiana. The pilot reported that during his initial departure at 1400, there was a high exhaust gas temperature (EGT) indication. The pilot then returned to PLK where a mechanic looked at the mixture control. The pilot stated that during a second departure attempt, the aircraft would not continue to climb after the gear was retracted at an altitude of approximately 100 feet. He further stated that the engine apparently continued to decrease in power output and that he maintained a low downwind to Runway 29, turned to line up with the runway, and impacted the tarmac. The Airport Operations Manager reported that he saw the aircraft with its landing gear in the down position and that he had heard the engine running very rough. He also noted that the aircraft was banking steeply trying to turn to the centerline of the runway. He further reported that the aircraft's left wing struck the gravel on the south side of the runway, the right main gear broke free and, the nose gear folded up. He added that the aircraft slid towards the centerline of the runway and came to rest approximately 300 feet after its initial impact point which was located approximately 450 feet beyond the threshold of Runway 29. The Airport Manager also stated that the nose of the aircraft was orientated 30 - 40 degrees right of the runway's centerline. The pilot reported that the mechanic, who inspected the mixture control, had replaced the outer mixture control clamps. The pilot also stated that the mechanic recommended to leave the control full rich until a mechanic could troubleshoot the reason that the control linkage allowed the mixture to go over center. The pilot stated that no paperwork was done on the clamp replacement and that the mechanic did not want to charge for the work. The mechanic stated that he was told that the pilot could not shut down the engine with the mixture control, and that the pilot had to use the key. The mechanic stated that he was not told about the attempted departure, or that the pilot had noted a high EGT and had experienced a "partial power loss". The mechanic stated, that he had replaced a cable housing clamp and rigged the mixture control to the full rich stop. He also told the pilot that it was still not rigged correctly and would take a week to troubleshoot and repair. The mechanic further reported, that he showed the discrepancy to the pilot and told him he could do whatever he wanted to do. The mechanic stated that he did not make a logbook entry and did not issue a work order. Inspection of the aircraft by a Federal Aviation Inspector revealed that there was fuel present in both fuel tanks. Both magnetos were tested and no anomalies were noted. Inspection of the mixture control revealed that it was not travelling to the idle cut-off stop and that the full rich stop pin was not in place. ## Aircraft - Registration: [N8946M](https://openairdocs.org/deregistered/N8946M-2013-07-17), registration cancelled 2013-07-17, S/N CD-707, built 1963 (OpenAirDocs) - Reported make and model: Beech BE-35 - Registry model: [Beech 35-B33](https://openairdocs.org/model/beech-35-b33) (registry code 1151406) (OpenAirDocs) - Registry engine: [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series) (registry code 17027, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: CD-707 - Airframe hours: 4897 - Engines: Continental IO-470K 225 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Dennis Watermann - Registered owner: Ray Lezina - Airworthiness certificate: Standard, Utility - Last inspection: Annual, April 3, 1998, 27 hours before - Destination: SLIDELL, LA - Flight plan: VFR - Airport: PLK, M. Graham Clark, runway 29, 3,739 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,312 total, 22 in this make and model, 1,124 as pilot in command, 22 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 72 °F - Altimeter: 29.00 inHg - Observed at: SGF ## 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 19980929027459A](https://openairdocs.org/incident/19980929027459A), Sep 29, 1998: Beech 35B33, Point Lookout, MO, Substantial damage. Acft experienced a loss of power on takeoff, returned to the aprt, and sustained substantial damage. (-23)the mixture control was improperly rigged. The pilot… ## Other investigations on N8946M (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 SEA68D0064](https://openairdocs.org/ntsb/SEA68D0064), Jun 3, 1967: Beech 35-B33 (N8946M), Westby, MT, substantial damage - [NTSB FTW67D0217](https://openairdocs.org/ntsb/FTW67D0217), Sep 21, 1966: Beech 35 (N8946M), Guymon, OK, substantial damage 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.