Burkhart Grob G103 TWIN ASTIR incident near Williamson, Georgia, January 31, 1987
On January 31, 1987 at about 5:25 pm local time, a Burkhart Grob G103 TWIN ASTIR (glider), registered N429BG, suffered minor damage in an incident near Williamson, Georgia (Peach State Gliderport airport). It was an instructional 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 NTSB has not yet published a probable cause for this incident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 31, 1987 · about 5:25 pm local time
- Place
- Williamson, Georgia · Peach State Gliderport · map
- Type
- Incident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Burkhart Grob G103 TWIN ASTIR G103 TWIN · all G103 TWIN ASTIRs on the register
- Registration
- N429BG · registry record · serial 3737
- Damage
- Minor damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
AS THE GLIDER PLT WAS APCHG THE ENTRY POINT FOR LANDING, HE CHECKED THE SPOILERS FOR OPERATION. THE SPOILERS EXTENDED, BUT WOULD NOT RETRACT. THERE WAS A SIGNIFICANT INCREASE IN THE SINK RATE & THE PLT REALIZED HE WOULD BE UNABLE TO REACH THE ARPT. SUBSEQUENTLY, HE LANDED THE GLIDER (SAILPLANE) APRX 1/4 MI NORTH OF THE ARPT. AN INVESTIGATION REVEALED THAT ABELLCRANK (PN 103B-4433) IN THE SPOILER CONTROL SYSTEM HAD FAILED AT TWO LOCATIONS ON THE CENTER BEARING HOUSING. A METALLURGICAL EXAM REVEALED THE BELLCRANK HAD FAILED FROM HIGH CYCLE, LOW STRESS FATIGUE. THE FAILURES OCCURRED AT THE EDGE OF FILLET-WELDS IN RELATIVELY SOFT, HEAT AFFECTED ZONES (HAZ). THE BELLCRANK HAD NOT BEEN SUBJECTED TO POST WELD HEAT TREATMENT. TESTS VERIFIED A SIGNIFICANT LOSS OF HARDNESS IN THE HAZ. THE GLIDER HAD A TOTAL FLT TIME OF 318 HRS WHEN THE BELLCRANK FAILED.
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
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 4,965 hours in all; 6 in this make and model; 164 in the last 90 days; 4,780 as pilot in command
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: frt
The aircraft
- Airframe total time: 1,341 hours
- Last inspection: 100-hour inspection; 20 hours since
- Maximum gross weight: 1,435 lb
- Seats: 2
- Landing gear: fixed
- Engine: Unknown UNK (type not recorded); 0 hours total
The flight
- Flight plan: none
- Runway 31, 3,300 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 330° at 13 knots
- Visibility: 15 statute miles
- Sky: scat
- Temperature: 46°F (8°C), dew point 19°F (-7°C)
- Altimeter: 30.00 inHg
- Observation at 5:53 pm from ATL, 15 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| 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.