Let L-23 SUPER BLANIK accident near Gregory, Michigan, June 21, 2023
On June 21, 2023 at about 7:30 pm local time, a 1991 Let L-23 SUPER BLANIK (glider), registered N10BR, was substantially damaged in an accident during approach (VFR pattern final) near Gregory, Michigan. It was an instructional flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The flight instructor’s failure to maintain adequate airspeed and his exceedance of the glider’s critical angle of attack, leading to an aerodynamic stall during the off-field landing.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 21, 2023 · about 7:30 pm local time
- Place
- Gregory, Michigan · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Let L-23 SUPER BLANIK, built 1991 · all L-23 SUPER BLANIKs on the register
- Registration
- N10BR · registry record · serial 917826
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The student pilot reported that he was flying the glider until about 10 minutes before the accident, when the flight instructor took over control and started looking for thermals to gain altitude. He said the flight instructor was mostly quiet until he said they were going to perform an off-field landing. The glider flew across a tree line about 150 ft above ground level and turned to land in a bean field. Neither the student nor the flight instructor had any recollection of the accident. Postaccident examination showed that the forward fuselage was crushed upward, and rearward and the outboard 6 ft of the left wing was separated. The separation point had signatures indicating upward bending of the tip. The damage to the glider was consistent with a nose-low, left-wing-low impact. Flight control continuity was verified from the cockpit to all control surfaces. No anomalies were detected. Based on the available information, the glider likely had insufficient altitude to return to the departure airstrip and the flight instructor attempted an off-field landing. The nose-low, left-wing-low impact suggested that the instructor likely exceeded the glider’s critical angle of attack and encountered an aerodynamic stall at low altitude during the landing attempt.
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
- Aerodynamic stall/spin during approach (VFR pattern final) defining event
The NTSB's findings
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Capability exceeded
- Personnel issues › Task performance › Use of equip/info › Aircraft control › Instructor/check pilot
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: glider; instructor: instrument airplane; instrument: airplane; rotorcraft: glider
- Flight time: 24,700 hours in all; 130 in this make and model
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rear
- Injury: serious injuries
Dual student
- Flight time: 4 hours in all; 3 in this make and model
- Medical certificate: None
- Seat: frt
- Injury: minor injuries
The aircraft
- Last inspection: annual inspection, May 5, 2023
- Seats: 2
- Landing gear: fixed
- Operator: Sandhill Soaring Club INC
Weather at the time
- Light: daylight
- Wind: from 100° at 9 knots
- Visibility: 10 statute miles
- Sky: scat at 6,000 ft
- Temperature: 84°F (29°C), dew point 55°F (13°C)
- Altimeter: 30.13 inHg
- Observation at 3:35 pm from KOZW, 12 miles away
Weather report (METAR): METAR KOZW 211935Z AUTO 10009KT 10SM SCT060 SCT080 29/13 A3013 RMK AO2 T02910127=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
5 documents, released by the NTSB on November 21, 2024. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Maintenance Records | PDF, 4 pages | View Download |
| 2 | Email Correspondence with FAA Inspector | PDF, 4 pages | View Download |
| 3 | Email Correspondence with Flight Instructor | PDF, 2 pages | View Download |
| 4 | Email Correspondence with Father of Minor Student Pilot | PDF, 2 pages | View Download |
| 5 | Aircraft Examination Notes and Photographs | PDF, 9 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number CEN23LA254.