# NTSB LAX99LA312: Rockwell S-2R, N4168X, Acampo, CA, September 19, 1999 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 19, 1999, 16:56 local (23:56 UTC) - Place: Acampo, CA - Coordinates: 38.189407, -121.250213 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.1894&lon=-121.2502&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report April 6, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 47433 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX99LA312 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47433/pdf - Page: https://openairdocs.org/ntsb/LAX99LA312 ## Probable cause The pilot's failure to maintain runway alignment, which resulted in the aircraft encountering high vegetation, the loss of directional control, and collision with trees. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, takeoff - roll/run - terrain condition - high vegetation - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause) - proper alignment - not maintained, pilot in command (cause) - In flight collision with object, takeoff - initial climb - object - tree(s) - directional control - not maintained, pilot in command ## Analysis The private dirt strip is the size of a single lane road with vegetation, approximately 2 - 3 feet tall, and small trees on either side. On the takeoff roll, the left wheel and spreader became entangled in tall vegetation, which slewed the airplane to the left. The airplane became airborne and the left wing struck two trees. ## Factual narrative On September 19, 1999, at 1656 hours Pacific daylight time, a Rockwell S-2R, N4168X, collided with trees during takeoff from a private dirt airstrip near Acampo, California. The airplane, operated under the provisions of 14 CFR Part 91, was destroyed in a postimpact fire. The commercial pilot received minor injuries. Visual meteorological conditions existed for the local positioning flight, and no flight plan was filed. The flight was scheduled to terminate at the Lodi Airport, Lodi, California An on-scene investigation by a Federal Aviation Administration (FAA) inspector revealed that the airstrip is approximately the size of a single lane road. Grass, shrubs, and weeds approximately 2- to 3-feet tall, are located on both sides of the runway, with a series of trees that run along a railroad track on the left side of the runway. The inspector reported that the aircraft and engine logbooks, located onboard the airplane, were destroyed by a postimpact fire. The pilot stated in an interview with the FAA that he was moving his airplane to the Lodi airport because of the pending closure of the airstrip. The pilot stated that on the takeoff roll the left main wheel and the spreader got caught on the vegetation. This slewed the airplane to the left and then the left wing end cap struck a small tree. Before the pilot could recover directional control, the left wing struck a second tree. He stated that approximately 3 feet of the left wing was torn from the airplane, which then pitched up, turned 180 degrees, and impacted railroad tracks approximately 40 yards from the second tree. The pilot stated that the airplane had not flown since January, but the engine was started every couple of weeks to keep it lubricated. Witnesses to the accident stated that during the run-up no discrepancies were noted with the engine. They further reported that through the takeoff and accident sequence the engine sounded as if it was producing full power. Witnesses reported that during the takeoff roll the wings were level and it appeared that the spreader had become caught in the weeds. After the accident they assisted the pilot out of the airplane and noted smoke coming from the engine nacelle. They stated that there was an ensuing fire that spread from the engine nacelle downward and then up into the cockpit. The pilot did not complete the NTSB Form 6120.1/2, Pilot/Operator Aircraft Accident Report, despite repeated attempts by Safety Board investigators to obtain the information. ## Aircraft - Registration: [N4168X](https://openairdocs.org/deregistered/N4168X-2013-07-19), registration cancelled 2013-07-19, S/N 1937R, built 1974 (OpenAirDocs) - Reported make and model: Rockwell S-2R - Registry model: [Rockwell International S-2R](https://openairdocs.org/model/rockwell-international-s-2r) (registry code 7630202) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1937R - Engines: P&W R1340 600 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Positioning, Part 91 - Registered owner: William E. Chapman - Airworthiness certificate: Special, Restricted (Special) - Destination: 1O3, LODI, CA - Airport: Pvt Dirt Airstrip ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 16,200 total ## Weather - Conditions: Visual (VMC), Day - Wind: 330° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 57 °F - Altimeter: 29.00 inHg - Observed at: SKC, 40 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 19990919027809A](https://openairdocs.org/incident/19990919027809A), Sep 19, 1999: Ayres S2R, Acampo, CA, Substantial damage. (.19) On September 19, 1999, at 1706 hours pacific daylight time, a rockwell S-2R, N4168X, collided with trees after takeoff from a Private airstrip near… ## Other investigations on N4168X (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 FTW79DRJ14](https://openairdocs.org/ntsb/FTW79DRJ14), Jun 19, 1979: Rockwell S2R (N4168X), Garland, AR, 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.