Burkhart Grob Flugzeugbau G103 TWIN ASTIR accident near Gregory, Michigan, June 3, 2026
On June 3, 2026 at about 8:00 pm local time, a 1983 Burkhart Grob Flugzeugbau G103 TWIN ASTIR (glider), registered N4101M, was substantially damaged in an accident during landing near Gregory, Michigan (Richmond Field Airport). It was an instructional flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The flight instructor’s improper planning during the simulated aborted launch which resulted in a touchdown on unsuitable terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 3, 2026 · about 8:00 pm local time
- Place
- Gregory, Michigan · Richmond Field Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Burkhart Grob Flugzeugbau G103 TWIN ASTIR, built 1983 · all G103 TWIN ASTIRs on the register
- Registration
- N4101M · registry record · serial 3796
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight instructor reported that while practicing an immediate landing after liftoff, with the student pilot at the flight controls, the glider landed past the end of the runway in tall grass on a downward sloping hill. The left wing lowered and the glider pivoted and came to rest in a muddy area. The rudder sustained substantial damage during the landing. The flight instructor reported that there were no preaccident mechanical malfunctions or failures with the glider that would have precluded normal operation. The flight instructor remarked that in the future he would plan to terminate the tow earlier so there would be sufficient runway remaining to land on and brief whether the terrain beyond the runway was suitable for landings.
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
- Simulated/training event during initial climb
- Dragged wing/rotor/float/other during landing defining event
The NTSB's findings
- Personnel issues › Task performance › Communication (personnel) › Issuing instructions › Instructor/check pilot
- Aircraft › Aircraft oper/perf/capability › (general) › (general) › Incorrect use/operation
- Environmental issues › Physical environment › Terrain › Sloped/uneven terrain › Awareness of condition
Pilot
- Certificate: airline transport pilot, flight instructor, flight engineer
- 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: 24,908 hours in all; 24 in the last 90 days; 1 in the last 30 days; 14,806 as pilot in command; 3,237 on instruments
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: rear
- Injury: no injuries
Dual student
- Certificate: student
- Flight time: 52.5 hours in all; 28.3 in this make and model; 5.1 in the last 90 days; 0.9 in the last 30 days; 8.9 as pilot in command
- Medical certificate: None
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 4,764.9 hours
- Last inspection: inspection type not recorded, November 15, 2025
- Maximum gross weight: 1,435 lb
- Seats: 2
- Landing gear: fixed
- Operator: Sandhill Soaring Club Inc.
The flight
- Departed from: 69G Gregory MI at 8:00 pm
- Flight plan: none
- Runway 18, 2,471 ft by 100 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 240° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 79°F (26°C), dew point 52°F (11°C)
- Altimeter: 30.01 inHg
- Observation at 3:53 pm from KHTL, 27 miles away
Weather report (METAR): METAR KHTL 031953Z AUTO 24004KT 10SM CLR 26/11 A3001 RMK AO2 SLP159 T02560111=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Photographs from the investigation 3 pictures from the NTSB's docket, as the NTSB released them
Photograph 1 – Accident glider vertical stabilizer
Photograph 2 – Accident glider rudder damage
Photograph 3 – Accident glider composite damageThe NTSB's photographs with the NTSB's captions, at screen size. Open a picture to see it full size or to report one that should not be shown.
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on September 11, 2026. 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 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 10 pages | View Download |
| 2 | Photos | PDF, 4 pages · our copy | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Other NTSB records under N4101M the same tail number, which may have belonged to a different aircraft at the time
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.