DEN01LA117 · Piper PA-12
Piper PA-12 · Accident: in flight encounter with weather on approach
From 1V5 · Boulder, CO to 1V5 · Boulder, CO
Event
- NTSB case
- DEN01LA117
- 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
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- 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
Piper PA-12
- Aircraft type
- Piper PA-12
- 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
- N7850H
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From 1V5 · Boulder, COTo 1V5 · Boulder, 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
- Approach · VFR pattern final
- 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
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Pilot in command › In-flight planning/decision, inadequate
- Pilot in command › Weather evaluation, inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was practicing off runway landings in the tundra at approximately 11,000 feet. He selected a landing area, made a few passes to inspect the site, and decided to land uphill. On short final, he "realized that my sink rate was higher than I was comfortable with, and my groundspeed was too high." He applied full power, but contacted the ground while the airplane was in a crab. Both main landing gear were broken off, and the wings were bent. The pilot said that after he exited the airplane, he noted that he had landed with a 20 knot quartering tailwind. He also stated that the ambient air temperature at the crash site was 60 degrees Fahrenheit. The calculated density altitude was 13,418 feet.
Probable cause
the pilot's inadequate wind evaluation, and his inadequate planning/decision to land with a tailwind, at a density altitude of 13,418 feet. Contributing factors were the tailwind and the high density altitude weather condition.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN01LA117
- Event ID
- 20010706X01317
- Case number
- DEN01LA117
- 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: c1f8685e4693d12fe8a0797d4a8c1dd02730dec2a1408a787d3eb47c196ee224; retrieved 2026-09-22T11:50:34.118Z.