# NTSB NYC02LA046: Let L-23, N117BB, Sterling, MA, January 1, 2002 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 1, 2002, 14:58 local (18:58 UTC) - Place: Sterling, MA - Coordinates: 42.454723, -71.733329 - Nearby events: https://openairdocs.org/map.md?lat=42.4547&lon=-71.7333&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 25, 2003 - Report: Approved by Office Director - Parties: FAA - NTSB case key (mKey): 53996 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC02LA046 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/53996/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=53996 - Page: https://openairdocs.org/ntsb/NYC02LA046 ## Probable cause The student pilots inadequate compensation for wind conditions which resulted in an off-field landing, and the CFI's improper decision to allow the student to fly solo. Factors related to the accident were the gusting wind conditions, and the students lack of total experience in gliders. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, emergency descent/landing - compensation for wind conditions - inadequate, pilot in command (cause) - lack of total experience in kind of aircraft, pilot in command (contributing factor) - object - fence - weather condition - gusts (contributing factor) - planning/decision - improper, flight instructor(on ground) (cause) ## Analysis As the glider neared the airport, the student pilot entered the downwind leg further out from the runway than she normally would. As the glider was turned on to the base leg, the student realized that she would not make the runway and elected to perform a forced landing to a two-lane highway. The glider touched down on the southbound lane of the elevated roadway, impacted a metal guardrail, and came to rest upright. The student had accumulated about 13 hours of dual instruction in gliders, with 7 or 8 different flight instructors, and about 1.4 hours of solo time. The student added that previous to the accident flight, she had no plans to fly solo due to the wind conditions. After her flight instructor reassured her that the pervious dual flight had been good, and student climbed into the glider alone. The recorded weather at a nearby airport, about the time of the accident, included winds from 250 degrees at 13 knots, gusts to 22 knots. ## Factual narrative On January 1, 2002, about 1458 eastern standard time, a LET L-23 glider, N117BB, was substantially damaged during a forced landing near the Sterling Airport, Sterling, Massachusetts. The student pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the instructional flight conducted under 14 CFR Part 91. According to the student pilot, the accident flight was the second flight of the day, which was conducted solo. The first flight was about 3-1/2 hours earlier, and was conducted with an instructor. The student added that it was windy on the flight, and she had no plans to solo due to the wind conditions. When the flight instructor asked her if she wanted to fly again, she said yes, assuming the flight would be conducted as dual instruction. When the student realized that the flight would be conducted solo, she replied that she did not want to go solo, and that it was still too rough. After the flight instructor reassured her that the pervious dual flight had been good, the student climbed into the glider alone. On the solo flight, as the glider was towed behind a tow plane, the student observed that the wind was blowing down the favored runway, runway 34. During the tow to altitude, the conditions were rough, with the towline going slack, and then tight, requiring the student to make corrections more often then she had done in the past. As the glider approached 2,500 feet, the towline was released and the student began to practice maneuvers. During the maneuvers, the student stated that she hit her head twice on the canopy due to the turbulent conditions. About 12 minutes into the flight, the student decided to return to the airport. She entered the traffic pattern, on the downwind leg, at 1,500 feet, but further out from the runway than she normally would have flown. While on the downwind leg, the student checked the operation of the airbrake and kept her hand on it as she had been taught. As the glider was turned on to the base leg, the student realized that she would not make the runway and elected to perform a forced landing to a two-lane highway. The glider touched down on the southbound lane of the elevated roadway and impacted a metal guardrail, coming to rest upright on the highway. The student additionally stated that she might have been moving the speed brake handle inadvertently during the approach due to the turbulence. The student reported she had accumulated about 13 hours of dual instruction, with 7 or 8 different flight instructors, at the Massachusetts Institute of Technology Soaring Club. She also accumulated about 1.4 hours of solo time. All of her previous flights had been conducted on days with light or calm wind conditions, with some crosswind landings. The recorded weather at a nearby airport, about the time of the accident, included winds from 250 degrees at 13 knots, gusts to 22 knots. ## Aircraft - Registration: [N117BB](https://openairdocs.org/deregistered/N117BB-2004-05-05), registration cancelled 2004-05-05, S/N 917815, built 1991 (OpenAirDocs) - Reported make and model: LET L-23 - Registry model: [Let L-23 SUPER BLANIK](https://openairdocs.org/model/let-l-23-super-blanik) (registry code 1360308) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Glider - Serial number: 917815 - Airframe hours: 911 - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: M.I.T. Soaring Association - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, August 27, 2001, 25 hours before - Departed: 3B3, Sterling, MA - Airport: 3B3, Sterling Airport, runway 34, 3,010 × 40 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Student pilot; age 36; injuries: none; student; seat: front; flight hours: 17 total, 17 in this make and model, 2 as pilot in command, 10 in the last 90 days, 4 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 18 knots, gusting 22 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 30 °F, dew point 9 °F - Altimeter: 29.93 inHg - Observed at: FIT, 5 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 20020101000299A](https://openairdocs.org/incident/20020101000299A), Jan 1, 2002: Let L23SUPERBLAN, Sterling, MA, No damage. (-23) The student pilot was unable to glide to the airport on the turns from downwind, to base, and to final in windy and turbulent conditions. The glider… ## Docket (3 files) The files NTSB released with the investigation on May 15, 2003, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=53996. 674 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 347 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40377050&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Statements (item 2, .PDF, 284 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40377051&FileExtension=.PDF&FileName=Pilot%20Statements-Redacted.PDF - Weather Reports and Records (item 3, .PDF, 42 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40182686&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF 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.