Eiriavion Oy PIK 20B accident near Sterling, Massachusetts, June 16, 2011
On June 16, 2011 at about 7:00 pm local time, a Eiriavion Oy PIK 20B (glider), registered N99136, was substantially damaged in an accident during landing near Sterling, Massachusetts (Sterling Airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's misjudgment of the amount of flaps required to attain the proper touchdown point. Contributing to the accident was the pilot's limited experience in the high performance glider.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 16, 2011 · about 7:00 pm local time
- Place
- Sterling, Massachusetts · Sterling Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Eiriavion Oy PIK 20B · all PIK 20Bs on the register
- Registration
- N99136 · registry record · serial 20147C
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
According to the pilot, this was his first flight in this flap only, high performance glider. The glider was towed to 5,000 feet, where the pilot practiced pattern work as well as extending and retracting the flaps, from zero degrees to 90 degrees, while maintaining an adequate airspeed for landing. The pilot entered a tight traffic pattern at the airport and extended the flaps to 30 degrees. On the final leg of the traffic pattern, the glider was in line with the runway, and the pilot intended to extend the flaps to 45 degrees, but was unsure if he did so. When the glider was halfway down the runway, the pilot knew he had excessive airspeed and was going to land further down the runway than intended. Near the end of the runway, the pilot thought he landed so he pushed the controls forward in order to gain ground control, but the glider continued over trees past the end of the runway. Since the glider did not have enough altitude to safely turn back to the runway, the pilot landed it in trees resulting in substantial damage to the fuselage. The pilot stated that he accumulated 107 hours of total flight time in a glider, of which, no hours were in the same make and model as the accident glider. The pilot reported there were no preexisting mechanical anomalies with the glider.
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
- Landing area overshoot during landing defining event
- Collision during takeoff/land during landing
The NTSB's findings
- cause Personnel issues › Action/decision › Action › Incorrect action performance › Pilot
- factor Personnel issues › Experience/knowledge › Experience/qualifications › Total experience w/ equipment › Pilot
- cause Aircraft › Aircraft systems › Flight control system › TE flap control system › Incorrect use/operation
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Landing flare › Not attained/maintained
Pilot
- Certificate: private
- Ratings: rotorcraft: glider
- Flight time: 107 hours in all; 0 in this make and model; 2 in the last 90 days; 2 in the last 30 days; 63 as pilot in command
- Last flight review: June 29, 2009
- Medical certificate: None
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 2,200 hours
- Last inspection: annual inspection, May 7, 2011
- Maximum gross weight: 990 lb
- Seats: 1
- Landing gear: fixed
The flight
- Departed from: 3B3 Sterling MA at 6:15 pm
- Destination: 3B3 Sterling MA
- Flight plan: none
- Runway 34, 3,086 ft by 40 ft
Weather at the time
- Light: daylight
- Wind: from 240° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 88°F (31°C), dew point 52°F (11°C)
- Altimeter: 29.86 inHg
- Observation at 6:52 pm from FIT, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
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 never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.