# NTSB CHI96LA197: Grumman American AA-1C, N39048, Custer, SD, June 8, 1996 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: June 8, 1996, 07:45 local (13:45 UTC) - Place: Custer, SD - Coordinates: 43.76015, -103.600418 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.7602&lon=-103.6004&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor, 1 uninjured - Status: Completed, report December 16, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 10275 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI96LA197 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10275/pdf - Page: https://openairdocs.org/ntsb/CHI96LA197 ## Probable cause the pilot did not maintain aircraft control or abort the takeoff. The factors involved were the pilot encountered a stall/mush condition, exhaust valves were leaking, low compression on all cylinders, and all pistons were scored. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, takeoff - initial climb - engine assembly,piston - scored (contributing factor) - aborted takeoff - not performed, pilot in command (cause) - engine assembly,cylinder - low compression (contributing factor) - engine assembly,valve,exhaust - leak (contributing factor) - Forced landing, emergency landing after takeoff - airport facilities,runway overrun area - downhill - aircraft control - not maintained, pilot in command (cause) - stall/mush - encountered, pilot in command (contributing factor) - In flight collision with terrain/water, emergency landing ## Analysis After takeoff, the airplane would not climb and began to settle back on the runway. The passenger heard the stall horn come on and off. The pilot made an emergency landing beyond the overrun area. Examination of the engine revealed low compression readings on all cylinders, all four pistons badly scored and burned and leaking exhaust valves. ## Factual narrative On June 08, 1996, at 0745 mountain daylight time (mdt), a Grumman American AA-1C, N39048, owned and operated by a commercial pilot, was substantially damaged during a forced landing, shortly after takeoff from runway 25 at Custer County Airport, South Dakota, following a loss of engine power. The pilot reported no injuries and passenger reported minor injuries. Visual meteorological conditions prevailed at the time of the accident. The personal 14 CFR Part 91 flight was not operating on a flight plan. The flight departed Custer County Airport, Custer, South Dakota, at 0745 mdt. According to the pilot's written statement, he performed a successful runup and departed runway 25 with a five to seven knot quartering headwind. After takeoff, the pilot noticed a decrease in climb performance. The terrain was downsloping with trees ahead, so he elected to perform a forced landing in a field. He said that the night before the engine was running rough on the right magneto and he corrected the problem by leaning the mixture at full power. The pilot believes there was a magneto failure. A written statement from the left seat passenger stated the airplane would not climb after takeoff and said, "I did hear the stall horn come on and off. We did touch back down on the overrun area, I think for just an instant." A forced landing followed. A local mechanic was flying that day and heard over the unicom frequency "you take it, you take it" at the time of the accident. He flew back to investigate. He examined the engine, and found low compression readings on all cylinders, leaking exhaust valves, a grit residue on the cylinder walls, all four pistons badly scored and burned and excessive carbon buildup on the pistons. ## Aircraft - Registration: [N39048](https://openairdocs.org/deregistered/N39048-1999-01-22), registration cancelled 1999-01-22, S/N AA1C0202 (OpenAirDocs) - Reported make and model: Grumman American AA-1C - Registry model: [Grumman American Avn. AA-1C](https://openairdocs.org/model/grumman-american-avn-aa-1c) (registry code 3960100) (OpenAirDocs) - Category: Airplane - Serial number: 0202 - Airframe hours: 2066 - Engines: Lycoming O-235-L2C 115 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Gary C. Holst - Airworthiness certificate: Standard, Utility - Last inspection: Annual, July 25, 1996, 45 hours before - Departed: SD01 - Destination: EFC, BELLE FOURCHE, SD - Airport: SD01, Custer County Airport, runway 25, 4,700 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 890 total, 50 in this make and model, 800 as pilot in command, 40 in the last 90 days, 12 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °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 19960608013249A](https://openairdocs.org/incident/19960608013249A), Jun 8, 1996: Amrgen AA1C, Custer, SD, Substantial damage. Aircraft descended into an off airport landing after reaching approax 200FT AGL during departure from airport. (.4)after takeoff, the airplane would not climb… 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.