# NTSB NYC07CA151: Let Super Blanik L-23, N8022, Warren, VT, June 27, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 27, 2007, 16:30 local (20:30 UTC) - Place: Warren, VT - Coordinates: 44.116664, -72.826667 - Nearby events: https://openairdocs.org/map.md?lat=44.1167&lon=-72.8267&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report October 31, 2007 - Report: Approved by Office Director - Parties: FAA/FSDO - NTSB case key (mKey): 66628 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC07CA151 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66628/pdf - Page: https://openairdocs.org/ntsb/NYC07CA151 ## Probable cause The glider's inadvertent encounter with windshear. A factor was the outflow from a nearby thunderstorm. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - vfr pattern - final approach - weather condition - windshear (cause) - weather condition - thunderstorm,outflow (contributing factor) - Loss of control - in flight, approach - vfr pattern - final approach - proper descent rate - not possible, pilot in command(cfi) - Hard landing, approach - vfr pattern - final approach - terrain condition - ground ## Analysis The LET Super Blanik L23 flight instructor and a student pilot were towed to 2,700 feet above the airport, where the student pilot performed a series of maneuvers. Afterwards, the student pilot descended the glider toward a midfield downwind entry, about 1,500 feet above the airport. While descending, turbulence from an approaching rain shower increased, so the flight instructor took the controls. The flight instructor flew the remainder of the downwind leg, followed by a base leg, at 70 knots with full spoilers deployed since the glider would not descend. Turning onto final, while heading into the wind, the glider experienced an "extremely strong" sink rate, from which, the flight instructor could not recover. The glider subsequently landed hard about 100 feet short of the runway causing substantial damage. Shortly after the landing, light rain fell on the airport, and there was thunder in the distance. Ten minutes later, there was lightning 2 miles southeast of the airport, and the winds dropped and remained at less than 10 knots the rest of the afternoon. The flight instructor reported over 9,600 hours of flight time with 3,700 hours as a pilot in command of gliders. ## Factual narrative According to the LET Super Blanik L23 flight instructor, he and a student pilot were towed to 2,700 feet above the airport, where the student pilot performed a series of maneuvers. Afterwards, the student pilot descended the glider toward a midfield downwind entry, about 1,500 feet above the airport. While descending, turbulence from an approaching rain shower increased, so the flight instructor took the controls. The flight instructor flew the remainder of the downwind leg, followed by a base leg, at 70 knots with full spoilers deployed since the glider would not descend. Turning onto final, while heading into the wind, the glider experienced an "extremely strong" sink rate, from which, the flight instructor could not recover. The glider subsequently landed hard about 100 feet short of the runway causing substantial damage. Shortly after the landing, light rain fell on the airport, and there was thunder in the distance. Ten minutes later, there was lightning about 2 miles southeast of the airport, and the winds dropped and remained at less than 10 knots the rest of the afternoon. The flight instructor reported over 9,600 hours of flight time with 3,700 hours as a pilot in command of gliders. ## Aircraft - Registration: [N8022](https://openairdocs.org/deregistered/N8022-2014-11-25), registration cancelled 2014-11-25, S/N 938022, built 1993 (OpenAirDocs) - Reported make and model: LET Super Blanik L-23 - Registry model: [Let L-23 SUPER BLANIK](https://openairdocs.org/model/let-l-23-super-blanik) (registry code 1360308) (OpenAirDocs) - Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs) - Category: Glider - Serial number: 938022 - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Sugarbush Soaring Association - Airworthiness certificate: Standard, Normal - Departed: 0B7, Warren, VT - Airport: 037, Warren-Sugarbush, runway 22, 2,300 × 30 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 59; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2; flight hours: 9,610 total, 1,800 in this make and model - Student pilot; injuries: none ## Weather - Conditions: Visual (VMC), Day - Wind: 240° at 10 knots, gusting 24 - Visibility: 10 statute miles - Temperature: 70 °F - Altimeter: 29.89 inHg - Observed at: MPV, 12 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 20070627830549A](https://openairdocs.org/incident/20070627830549A), Jun 27, 2007: Let L23SUPERBLAN, Warren, VT, Substantial damage. (-23) Not on scene. Weather was VMC per mvp weather reporting at the time of the operation. Wind was reported as 300' @12 with 4700-6000 scattered visibility… 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.