# NTSB SEA04LA099: Grumman G-164B, N8440K, Midvale, ID, June 5, 2004 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: June 5, 2004, 08:30 local (14:30 UTC) - Place: Midvale, ID - Coordinates: 44.500831, -116.804725 - Nearby events: https://openairdocs.org/map.md?lat=44.5008&lon=-116.8047&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report October 28, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 59390 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA04LA099 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59390/pdf - Page: https://openairdocs.org/ntsb/SEA04LA099 ## Probable cause The failure of the pilot to maintain clearance from the high tension powerline. A factor was the powerline. ## 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 - clearance - not maintained, pilot in command (cause) - object - wire,transmission (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis While spraying a field from east to west and working under high tension powerlines, which ran diagonally across the field from the southeast to the northwest, the aircraft impacted one of the powerlines that was lower than the others. The aircraft impacted terrain and was subsequently destroyed as it was consumed by fire. ## Factual narrative On June 5, 2004, approximately 0830 mountain daylight time, a Grumman G-164B agricultural airplane, N8440K, was destroyed after impacting high tension power lines while maneuvering near Midvale, Idaho. The commercial pilot, sole occupant of the airplane, sustained serious injuries. The airplane was registered to Weiser Air Service, Weiser, Idaho, and operated under 14 CFR Part 137. Visual meteorological conditions prevailed for the aerial application flight, and a flight plan was not filed. The flight departed the Lee Williams Memorial Airport, Midvale, Idaho, at approximately 0745. According to the Pilot/Operator Aircraft Accident Report (NTSB form 612.1/2), the pilot reported that he was dispensing his load in an east to west direction while working under high tension power lines which traversed the field diagonally. The pilot stated that he impacted one of the power lines, which was lower than the others while making a spray pass to the west. The aircraft subsequently impacted terrain where it came to rest in an upright position prior to being destroyed as it was consumed by fire. The pilot reported to the NTSB investigator-in-charge that no anomalies existed prior to or during the flight which would have precluded normal operations. ## Aircraft - Registration: [N8440K](https://openairdocs.org/deregistered/N8440K-2014-11-20), registration cancelled 2014-11-20, S/N 694B, built 1982 (OpenAirDocs) - Reported make and model: Grumman G-164B - Registry model: [Grumman Acft ENG Cor-Schweizer G-164B](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164b) (registry code 3952802) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 694B1 - Airframe hours: 7804 - Engines: Pratt & Whitney R-1349 600 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Aerial application, Part 137 - Registered owner: Weiser Air Air Service Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, May 15, 2004 - Departed: 0U9, Midvale, ID ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; injuries: serious; commercial; airplane ratings: single-engine land, multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; last flight review February 15, 2003; seat: center; flight hours: 18,055 total, 11,049 in this make and model, 17,566 as pilot in command, 148 in the last 90 days, 54 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 54 °F - Altimeter: 29.89 inHg - Observed at: ONO, 15 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 20040605010229A](https://openairdocs.org/incident/20040605010229A), Jun 5, 2004: Scwzer G164B, Midvale, ID, Destroyed. (-23) The pilot was spraying alfalfa flying east and west in rolling terrain, while flying under high voltage powerlines/towers. On the last pass witnesses… ## Other investigations on N8440K (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 SEA02LA123](https://openairdocs.org/ntsb/SEA02LA123), Jul 6, 2002: Grumman-Schweizer G-164B (N8440K), Weiser, ID, substantial damage. Probable cause: The fracture of the number 3 cylinder exhaust pushrod resulting in the exhaust valve's inability to open during the exhaust cycle and the subsequent engine stoppage. Contributing factors were the… 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.