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Accidents · NTSB SEA08CA122 · Final report

Schempp-Hirth Nimbus-4M accident near Ephrata, Washington, May 4, 2008

On May 4, 2008 at about 9:22 pm local time, a Schempp-Hirth Nimbus-4M (glider), registered N747JN, was substantially damaged in an accident during initial climb near Ephrata, Washington (Ephrata Municipal Airport). It was a personal flight under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).

The NTSB's probable cause their words, unchanged

The pilot's inadequate preflight inspection and his failure to connect the left aileron control rod during assembly.

Source: NTSB aviation accident database, copy made October 12, 2026. Docket and reports at the NTSB.

What the record shows

Date
May 4, 2008 · about 9:22 pm local time · cases in 2008
Place
Ephrata, Washington · Ephrata Municipal Airport · cases near this airport · map
Type
Accident
Injuries
1 person was seriously injured.
Weather
visual conditions (good weather)
Aircraft
Schempp-Hirth Nimbus-4M · all Nimbus-4Ms on the register
Registration
N747JN · registry record · serial 14
Damage
Substantial damage
Flight
Personal flight · general aviation rules (Part 91)

The NTSB's narrative final · quoted from the NTSB record

This was the first flight after removal of the glider from storage and its reassembly. The pilot reported that during takeoff initial climb, the glider started to roll to the left despite his control inputs. He decided to abort the takeoff and land straight ahead while attempting to maintain control of the powered glider. Subsequently, the left wing struck the ground, and the glider began to cartwheel. Examination of the airframe revealed that the left and right wings were structurally damaged and the empennage was partially separated. Examination of the flight control system revealed that the left aileron connecting rod was disconnected at the fuselage/wing quick connection point and was undamaged. The pilot stated that during assembly of the glider prior to the flight, the left aileron control tube was inadvertently not attached, and that he did not verify that all flight controls moved free and correct prior to takeoff.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.

The factual record from the NTSB's investigation tables, in plain English

What happened, in order

  1. Loss of control in flight during initial climb defining event
  2. Collision with terrain or object (not controlled flight into terrain) during takeoff

The NTSB's findings

  • cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Not inspected other cases naming the flight controls
  • cause Personnel issues › Task performance › Inspection › Preflight inspection › Pilot
  • cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot

Pilot

  • Certificate: commercial pilot
  • Ratings: single-engine land; rotorcraft: glider
  • Flight time: 5,000 hours in all; 1,500 in this make and model
  • Medical certificate: Class 3
  • Seat: ctr
  • Injury: serious injuries

The aircraft

  • Seats: 1
  • Landing gear: fixed
  • Engine: Solo 2625-02 (piston); 0 hours total

The flight

  • Departed from: KEPH Ephrata WA at 9:22 pm
  • Flight plan: none
  • Runway 21, 3,467 ft by 150 ft

Weather at the time

  • Light: daylight
  • Wind: at 4 knots
  • Visibility: 10 statute miles
  • Sky: clear
  • Temperature: 70°F (21°C), dew point 37°F (3°C)
  • Altimeter: 30.05 inHg
  • Observation at 8:53 pm from KEPH

Injuries

FatalSeriousMinorNone
Flight crew1

Documents from the investigation the NTSB's docket: the evidence folder behind the report

The NTSB has not released the docket for this case yet. The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), is usually released when the investigation is nearly complete, and the list here is refreshed when it appears. Check at the NTSB.

Connections how this case links to the rest of the register

Aircraft
Place

The whole map of how records connect · these connections as data: /graph/accident/SEA08CA122.json.

The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.

Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.