- Date
- September 23, 2019, 14:20 local (20:20 UTC)
- Place
- Boulder, CO
- Injuries
- 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N4785FPiper PA18
- Defining event
- Landing: Loss of control on ground
- Weather
- Visual (VMC) · Day
- Status
- Completed · report March 17, 2020
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20190923013579A
- Case key
- 100336
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot's failure to maintain directional control during the landing roll, which resulted in a ground loop.
Findings · 2
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
The pilot reported that he conducted a normal three-point landing. During the landing roll, the airplane ground looped to the left, and the left wing struck the ground. The airplane sustained substantial damage to the left wing spar and the rudder. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Factual narrative
The pilot in the tailwheel-equipped airplane reported that, he made a normal three-point landing. During the landing roll, the airplane ground-looped to the left, and the left wing struck the ground. The airplane sustained substantial damage to the left wing spar and the rudder. The airport's METAR reported that about the time of the accident, the wind was calm. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
Aircraft
- Registration
- N4785F
- Reported as
- Piper PA18 (150)
- Category
- Airplane
- Serial number
- 18-7906
- Built
- 1962
- Airframe hours
- 15,624.7
- Engine
- Lycoming O-360-A3A, 180 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Soaring Society Of Boulder Inc
- Registered owner
- Soaring Society Of Boulder Inc
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · June 7, 2019
- Departed
- BDU · Boulder, CO
- Destination
- BDU · Boulder, CO
- Airport
- BDU · Boulder Muni, runway 08, 4,100 × 75 ft, asphalt
- Equipment
- ADS-B
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 57
- Injuries
- None
- Certificates
- Flight instructor, Airline transport, Commercial
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, With waivers/limitations
- Last flight review
- August 16, 2019
- Seat
- Front
- Restraint
- 5-point
- Flight hours
- 20,403 total · 24 in this make and model · 6,169 as pilot in command · 58 in the last 90 days · 5 in the last 30 days · 0.5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Calm
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 77 °F, dew point 28 °F
- Altimeter
- 30.07 inHg
- Observed at
- KBDU, 1 nm away
Docket · 2
The files NTSB released with the investigation on January 3, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.7 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.
Other investigations on N4785F · 3
Matched to the same aircraft by N-number and date.