# NTSB ATL04LA065: Aero Commander 500, N800SL, Allendale, SC, January 11, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 11, 2004, 14:10 local (19:10 UTC) - Place: Allendale, SC - Coordinates: 32.990276, -81.268608 - Nearby events: https://openairdocs.org/map.md?lat=32.9903&lon=-81.2686&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 28, 2005 - Report: Approved by Office Director - Parties: Columbia FSDO - NTSB case key (mKey): 58598 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL04LA065 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/58598/pdf - Page: https://openairdocs.org/ntsb/ATL04LA065 ## Probable cause The failure of the hydraulic brake system accumulator due to a ruptured diaphragm. A factor was the ditch. ## 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 - landing gear,normal brake system (cause) - hydraulic system,accumulator - failure (cause) - Loss of control - on ground/water, takeoff - roll/run - directional control - not possible, pilot in command (contributing factor) - On ground/water encounter with terrain/water, takeoff - roll/run - terrain condition - ditch (contributing factor) ## Analysis According to the pilot, while on takeoff roll the airplane began to "track right", differential braking input was applied to line up the airplane with the runway center line. When brakes were applied to stop the airplane, they failed and the airplane veered off the left side of the runway into a ditch. Examination of the wheel brakes revealed that the hydraulic pucks were leaking, and the brake disc and linings were worn. Examination of the accumulator revealed the diaphragm was ruptured and the system would not maintain pressure. No other flight control or mechanical problems were reported by the pilot. ## Factual narrative On January 11, 2004, at 1410 eastern standard time, an Aero Commander 500, N800SL, registered to and operated by an airline transport pilot, collided with a ditch during an attempted takeoff at Allendale County Airport, Allendale, South Carolina. The personal flight was operated under the provision of Title 14 CFR Part 91 with no flight plan filed. Visual meteorological conditions prevailed at the time of the accident. The pilot and passenger were uninjured and the airplane sustained substantial damage. The flight was originating from Allendale County Airport, Allendale, South Carolina, on January 11, 2004 at 1400. According to the pilot, while on takeoff roll the airplane began to "track right", differential braking input was applied to line up the airplane with the runway center line. The pilot noticed that the brake pedal felt "soft" and aborted the takeoff. When brakes were applied to stop the airplane, they failed and the airplane veered off the left side of the runway into a ditch. Examination of the airplane revealed the outboard right wing was bent aft and curled upwards. The fuselage was buckled in the wing root area of left and right wing. No mechanical or flight control problems were reported by the pilot. Examination of the wheel brakes revealed that the hydraulic pucks were leaking, and the brake disc and linings were worn. Examination of the accumulator revealed the diaphragm was ruptured and the system would not maintain pressure. ## Aircraft - Registration: [N800SL](https://openairdocs.org/deregistered/N800SL-2005-02-25), registration cancelled 2005-02-25, S/N 740, built 1959 (OpenAirDocs) - Reported make and model: Aero Commander 500 - Registry model: [Aero Commander 500](https://openairdocs.org/model/aero-commander-500) (registry code 0141102) (OpenAirDocs) - Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 740 - Airframe hours: 2750 - Engines: Lycoming O-540 250 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: James H Plulee - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 1, 2003, 100 hours before - Departed: 88J, ALLENDALE, SC - Destination: 88J, ALLENDALE, SC - Flight plan: VFR - Airport: 88J, Allendale County, runway 35, 5,000 × 100 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: none; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; last flight review September 5, 2003; seat: left; flight hours: 2,263 total, 78 in this make and model, 2,188 as pilot in command, 10 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 39 °F, dew point 46 °F - Altimeter: 30.45 inHg - Observed at: KOGB, 34 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 20040111000649A](https://openairdocs.org/incident/20040111000649A), Jan 11, 2004: Gulstm 500, Allendale, SC, Substantial damage. (-23) On January 11, 2004, at 1410 local, an aero commander 500, N800SL, registered to and operated by an airline transport pilot, collided in a ditch during… 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.