CHI97LA239 · Briegleb BG-12A
Briegleb BG-12A · Accident: airframe, component or system failure en route
From Richard I Bong Memorial Airport (SUW) to an unrecorded destination
Event
- NTSB case
- CHI97LA239
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Briegleb BG-12A
- Aircraft type
- Briegleb BG-12
- Category
- Glider
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N5516V
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Richard I Bong Memorial Airport (SUW)To not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · climb to cruise
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Wing › Separation
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The glider was being towed when the pilot of the tow plane felt two hard tugs on the aircraft. He released the glider and started to turn to see the glider, but never saw it. A witness on the ground reported seeing objects falling from the sky. The right wing separated from the glider. The remainder of the glider impacted the ground inverted and nearly vertical. The wing was found 2 blocks from the main wreckage. Weight and balance computations showed the glider was 78 pounds over maximum gross weight, and the center of gravity was 19.7 inches. The limits for center of gravity are 17-18 inches over 100 miles an hour, and 17-19 inches under 100 miles an hour, due to the possibility of oscillations at the higher speeds. The glider pilot requested that the tow pilot tow the glider at 80-85 knots. 100 miles an hour equates to 86.7 knots.
Probable cause
the separation of the wing from the glider for undetermined reasons.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI97LA239
- Event ID
- 20001208X08572
- Case number
- CHI97LA239
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: c27087df9c06e025a87d938a2e20f3427034516d3be84913f698b56bb943d3a9; retrieved 2026-09-20T22:52:33.235Z.