FTW98FA299 · Grumman American AA-1A
Grumman American AA-1A · Accident: in flight encounter with weather en route
From 1C5 · Boulder, CO to Pueblo Memorial Airport (PUB)
Event
- NTSB case
- FTW98FA299
- 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
Grumman American AA-1A
- Aircraft type
- Grumman American AA-1
- Category
- Airplane
- 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
- N9453L
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From 1C5 · Boulder, COTo Pueblo Memorial Airport (PUB), Pueblo, CO
- 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 · 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
- In flight encounter with weather
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Stall/spin
- 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
- Pilot in command › Stall/spin, inadvertent
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The 265-hour private pilot filed a VFR flight plan from Boulder, Colorado, to Pueblo, Colorado, and requested VFR flight following services. Thirty minutes later, the pilot reported he was encountering 'moderate turbulence,' then 'quite a bit of turbulence,' that he was turning around, and requested flight following services back to Boulder. Shortly thereafter, the pilot advised he was in a spin and unable to correct and that he was turning off his transponder. The airplane struck the ground in a near-vertical attitude. There was no evidence of a spin. His logbook indicated he had never been demonstrated a spin or had been given spin instruction. The Pilot's Operating Handbook prohibits spins and states: 'There is evidence that permitting a spin to go beyond one turn without initiating proper recovery procedures can allow a spin mode to develop from which recovery is not possible.'
Probable cause
The pilot inadvertently stalling the airplane and entering an unrecoverable spin. A factor was clear air turbulence.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW98FA299
- Event ID
- 20001211X10553
- Case number
- FTW98FA299
- 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: 471bcbdd4e32d82539d9062fb8e40f31356f92736032a93f9e330b6596f51828; retrieved 2026-09-20T22:30:59.590Z.