# NTSB LAX98LA209: Glaser-Dirks DG-800B, N98NL, Jean, NV, June 21, 1998 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: June 21, 1998, 11:30 local (18:30 UTC) - Place: Jean, NV - Coordinates: 35.749191, -115.529655 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.7492&lon=-115.5297&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report August 3, 1999 - Report: Approved by Office Director - NTSB case key (mKey): 30129 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98LA209 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30129/pdf - Page: https://openairdocs.org/ntsb/LAX98LA209 ## Probable cause The disconnection of the elevator control attachment nut due to improper installation by the manufacturer, which resulted in the pilot's loss of control. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, approach - flt control syst,elevator control cable/rod - disconnected (cause) - maintenance,installation - improper, manufacturer (cause) - aircraft control - not possible, pilot in command - In flight collision with terrain/water, descent - uncontrolled ## Analysis The glider impacted terrain and the pilot reported that he lost elevator control. The bolt connecting the pushrod to the elevator was found, but the attaching nut was not found. The European production glider had a total time of 4 hours since manufacture. The metallurgist who examined the bolt reported the first three threads of the accident bolt did not have debris in the roots; however, proper engagement of the locknut would cause six threads to be free of debris. An exemplar locknut in the hand-tightened only position (without engaging the blue plastic lining of the locknut) caused the nut threads to wipe material from the roots of the first three bolt threads ## Factual narrative On June 21, 1998, at 1130 hours Pacific daylight time, a Glaser-Dirks DG-800B, N98NL, crashed short of the runway at the Jean, Nevada, airport. The glider sustained substantial damage. The commercial pilot, the sole occupant, suffered serious injuries. The personal flight was returning to the airport at the time and no flight plan was filed. Visual meteorological conditions prevailed. Witnesses reported that the aircraft was very low on the final approach and was oscillating. The aircraft impacted the terrain short of the runway in a level attitude. The cockpit was crushed and the pilot was removed by paramedics. The pilot reported that he lost elevator control. A Federal Aviation Administration inspector from the Las Vegas, Nevada, Flight Standards District Office examined the aircraft. He reported that the bolt connecting the pushrod to the elevator was found in the fuselage, but the attaching nut was not found. The European production aircraft had a total time since manufacture of 4 hours. The bolt and exemplar parts were examined with an optical microscope at Seal Laboratories in Los Angeles, California, on July 31, 1998, in the presence of the Safety Board. A copy of the laboratory report is appended to this file. According to the metallurgist, the first three threads of the accident bolt did not have debris in the roots, and installation of an exemplar locknut in the hand-tightened position would cause the nut threads to wipe material from the roots of the first three bolt threads. For proper tightening of the locknut, the threads must be engaged over the full height of 6 mm (six turns) so that the blue plastic lining which provides thread locking is deformed. This would require three more turns than are indicated by the lack of debris in the thread roots. The metallurgist concluded that a nut was installed on the bolt but not fully tightened. ## Aircraft - Registration: [N98NL](https://openairdocs.org/deregistered/N98NL-1998-11-10), registration cancelled 1998-11-10, S/N 8126B55 (OpenAirDocs) - Reported make and model: Glaser-Dirks DG-800B - Registry model: [DG Flugzeugbau DG-800B](https://openairdocs.org/model/dg-flugzeugbau-dg-800b) (registry code 3805015) (OpenAirDocs) - Category: Glider - Serial number: 8126B55 - Airframe hours: 4 - Engines: Solo 2-625-01 54 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: David Noyes - Registered owner: Safari-Glide Inc - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Unknown, April 1, 1998, 1 hours before - Departed: 0L7 - Airport: 0L7, Jean, runway 20R, 4,600 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; commercial, private, flight instructor; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: center; flight hours: 2,483 total, 1 in this make and model, 2,163 as pilot in command, 28 in the last 90 days, 2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 16 knots, gusting 20 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 91 °F, dew point 25 °F - Altimeter: 29.00 inHg - Observed at: LAS ## 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 19980621014519A](https://openairdocs.org/incident/19980621014519A), Jun 21, 1998: Glsdks DG800B, Jean, NV, Substantial damage. Glider lost elevator control and made an emerg landing in the desert. 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.