# NTSB SEA98LA171: Dornbos BD-4, N91LJ, Kent, WA, August 26, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 25, 1998, 19:15 local (Aug 26, 1998, 02:15 UTC) - Place: Kent, WA - Coordinates: 47.360065, -122.099983 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.3601&lon=-122.1000&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report February 15, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 43898 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA98LA171 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/43898/pdf - Page: https://openairdocs.org/ntsb/SEA98LA171 ## Probable cause Directional control was not maintained by the pilot in command. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, landing - roll - directional control - not maintained, pilot in command (cause) - On ground/water encounter with terrain/water, landing - roll ## Analysis The flight instructor reported that he performed a normal wheel-landing. During the landing roll, the airplane began to veer to the left of centerline. The flight instructor indicated to the commercial pilot, who was following on the controls, not to apply brakes. The flight instructor stated that he corrected the direction of travel back to centerline as the tail wheel was lowered. The airplane remained on centerline for several hundred feet, then began to veer to the right. The airplane continued to veer to the right and traveled off the runway at approximately mid-field. The airplane subsequently ground-looped before coming to rest on the grassy area between the runway and taxiway. The flight instructor reported that there were no mechanical failures or malfunctions with the airplane at the time of the accident. ## Factual narrative On August 25, 1998, approximately 1915 Pacific daylight time, an experimental BD-4, N91LJ, registered to and operated by the second pilot as a 14 CFR Part 91 instructional flight, ground-looped during the landing roll on runway 33 at Crest Airpark, Kent, Washington. Visual meteorological conditions prevailed and no flight plan was filed. The airplane was substantially damaged. Both the flight instructor and commercial pilot were uninjured. The flight originated from Crest Airpark for the local flight. During a telephone interview and subsequent written statement, the flight instructor reported that this flight was the first in a series of ten flights to check out the commercial pilot in the aircraft, and to prepare for his flight review. The flight instructor stated that a normal wheel-landing was made to runway 33 with the second pilot following on the controls. During the roll out, the airplane began to veer to the left. The flight instructor stated that he called out "no brakes" to the commercial pilot with the intention of no brake application until called for, as the right side position does not have brakes available. The flight instructor stated that he corrected the direction or travel back to centerline as the tail wheel was lowered. The airplane remained on the centerline for several hundred feet, then began to veer to the right. The airplane continued to veer to the right and traveled off the runway at approximately mid-field. The airplane subsequently ground-looped before coming to rest on the grassy area between the runway and taxiway. Both pilots reported that there were no mechanical failures or malfunctions with the airplane at the time of the accident. ## Aircraft - Registration: [N91LJ](https://openairdocs.org/aircraft/N91LJ), registered now, S/N 1, built 1992 (OpenAirDocs) - Reported make and model: Dornbos BD-4 - Registry model: [Dornbos John DORNBOS BD-4](https://openairdocs.org/model/dornbos-john-dornbos-bd-4) (registry code 11304H5) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1 - Airframe hours: 171 - Engines: Lycoming VO-360-A1B 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Duane J. Grindstaff - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, June 21, 1998, 3 hours before - Departed: S36, KENT, WA - Airport: S36, Crest Airpark, runway 33, 3,267 × 40 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; airline transport, flight engineer, commercial, flight instructor; airplane ratings: multi-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 3,331 total, 5 in this make and model, 1,940 as pilot in command, 85 in the last 90 days, 45 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 320° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 54 °F - Altimeter: 29.00 inHg - Observed at: SEA, 10 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 19980825047009A](https://openairdocs.org/incident/19980825047009A), Aug 25, 1998: Kent, WA, No damage. (-23)Aircraft was equipped with fully functioning dual controls, except there were no brakes on the right hand side. Aircraft was landed by instructor/pic… 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.