# NTSB LAX98LA233: Air Tractor AT-400, N2373V, Tranquillity, CA, July 17, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 16, 1998, 22:05 local (Jul 17, 1998, 05:05 UTC) - Place: Tranquillity, CA - Coordinates: 36.649967, -120.279647 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.6500&lon=-120.2796&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 22, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 43189 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98LA233 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/43189/pdf - Page: https://openairdocs.org/ntsb/LAX98LA233 ## Probable cause The pilot's failure to detect and avoid a set of wires during a night aerial application flight. Factors in the accident were the pilot's failure to perform an adequate preflight inspection of the field to determine obstruction locations and the dark night lighting conditions. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, maneuvering - aerial application - object - wire,transmission - light condition - dark night (contributing factor) - preflight planning/preparation - inadequate, pilot in command (cause) - visual/aural detection, pilot in command - visual lookout - restricted, pilot in command - clearance - inadequate, pilot in command (cause) ## Analysis The pilot said that this was the first flight at a new field, and he had not visually inspected the field before spraying it. He made a pass over the field to check for wires, and did not see any. On the second pass he saw a steel power cable strung between poles that was in his flight path. The pilot stated that it was too late to pull up to avoid the cable, and he pushed the nose of the aircraft down to fly underneath it. The aircraft, equipped with a wire deflector, struck a telephone wire underneath the initial steel cable. The wire deflector and the vertical stabilizer separated from the aircraft. The pilot began to lose directional and roll control, and he pushed the nose towards the ground and made a forced landing. The pilot stated that there were no mechanical malfunctions with the engine or flight controls prior to striking the wires. The night was dark with no moon. ## Factual narrative On July 16, 1998, at 2205 hours Pacific daylight time, an Air Tractor AT-400, N2373V, struck a telephone wire and made a forced landing in a tomato field near Tranquillity, California. The aircraft, operated by Western AG Aviation under 14 CFR Part 137, was on an aerial application flight and sustained substantial damage. The commercial pilot was not injured. Visual meteorological conditions existed for the night flight and no flight plan was filed. The pilot stated that this was the first flight at this field, and that he had not visually checked the field before going to spray it. He stated that he had made one pass from the north to the south to check for wires, and did not see any. On his second pass, he saw the steel cable strung between poles, but he was flying right into it and believed it was too late to pull up, so he pushed the nose of the aircraft down to fly underneath the wire. The aircraft was equipped with a wire deflector that hit a telephone wire underlying the steel cable. The pilot stated that the wire deflector broke, as well as the vertical stabilizer. The aircraft started to rotate to the left, as if it were going to roll over, and to stop that from happening he "pushed the nose into the ground," and landed immediately. In an interview with a Federal Aviation Administration inspector from the Fresno, California, Flight Standards District Office, the pilot reported that he flew under a power line, but did not see that there was a telephone line approximately 3-4 feet lower. The rudder of the aircraft struck the telephone line and he made a forced landing. The pilot did not note any mechanical malfunctions with the engine. The night was dark with no moon. ## Aircraft - Registration: [N2373V](https://openairdocs.org/deregistered/N2373V-2000-07-12), registration cancelled 2000-07-12, S/N 400-0426 (OpenAirDocs) - Reported make and model: Air Tractor AT-400 - Registry model: [Air Tractor AT-400](https://openairdocs.org/model/air-tractor-at-400) (registry code 0390202) (OpenAirDocs) - Category: Airplane - Serial number: 400-0426 - Airframe hours: 8189 - Engines: P&W PT-6A-15AG 680 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Western Ag. Aviation Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, July 2, 1998, 762 hours before - Departed: TRANQUILITY, CA ## 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: 20,000 total, 8,000 in this make and model, 20,000 as pilot in command, 200 in the last 90 days, 70 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Night/dark - Wind: 320° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 63 °F - Observed at: NLC, 25 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 19980716021219A](https://openairdocs.org/incident/19980716021219A), Jul 16, 1998: Airtrc AT400, Tranquillity, CA, Substantial damage. Severed top of vertical stabilizer on a unseen telephone line during night spray run. Ground looped landing. (-23) pilot performing aerial application at night… 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.