- Date
- July 21, 2001, 13:31 local (19:31 UTC)
- Place
- Great Falls, MT
- Injuries
- 3 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N2TSPilatus PC-6/B2-H4
- Weather
- Visual (VMC) · Day
- Status
- Completed · report August 26, 2003
- Report
- Approved by Office Director
- Parties
- Federal Aviation Administration
- FAA report
- 20010721025059A
- Case key
- 52799
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
Pilot's failure to maintain directional control of the aircraft while landing.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
According to a written report submitted by the operator, the pilot was landing the tail-wheel equipped airplane on runway 03. Shortly after touchdown, during the roll-out, the pilot manually unlocked the airplane's tail wheel. Upon releasing the tail-wheel lock, "...directional control of the airplane was lost." The airplane subsequently ground looped resulting in substantial damage to the right wing. The 1257 METAR observation at Great Falls reported winds from 070 degrees at 6 knots. The accident report submitted by the operator indicated that there were no mechanical malfunctions or failures with the aircraft that may have contributed to the accident.
Factual narrative
On July 21, 2001, at 1331 mountain daylight time, a Pilatus PC-6, airplane, N2TS, sustained substantial damage during the landing roll-out at Great Falls International Airport, Great Falls, Montana. The airplane is registered to N Bar Ranch, LLC, and was being operated as a visual flight rules (VFR) personal/pleasure flight under the provisions of Title 14, CFR Part 91, when the accident occurred. The airline transport pilot, and two passengers aboard the airplane, were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the cross-country flight. The flight originated from a private airstrip near Wolf Creek, Montana, approximately 15 minutes prior to the accident.
According to a written report submitted by the operator, the pilot was landing the tail-wheel equipped airplane on runway 03. Shortly after touchdown, during the roll-out, the pilot manually unlocked the airplane's tail wheel. Upon releasing the tail-wheel lock, "...directional control of the airplane was lost." The airplane subsequently ground looped resulting in substantial damage to the right wing.
The 1257 METAR observation at Great Falls reported winds from 070 degrees at 6 knots.
The accident report submitted by the operator indicated that there were no mechanical malfunctions or failures with the aircraft that may have contributed to the accident.
Aircraft
- Registration
- N2TS
- Reported as
- Pilatus PC-6/B2-H4
- Category
- Airplane
- Serial number
- 936
- Airframe hours
- 119.5
- Engine
- P&W Canada PT6A-27, 550 horsepower, turbo prop
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Thomas M. Siebel
- Registered owner
- N Bar Ranch LLC, C/O Dearborn Ranch
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · May 1, 2001 · 43.3 hours before
- Departed
- PVT · Wolf Creek, MT
- Destination
- GTF · Great Falls, MT
- Airport
- GTF · Great Falls Intl, runway 030, 10,500 × 150 ft, asphalt
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
- 48
- Injuries
- None
- Certificates
- Commercial, Airline transport
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 3, Valid Medical--no waivers/lim.
- Last flight review
- February 21, 2001
- Seat
- Left
- Flight hours
- 2,850 total · 50 in this make and model · 2,080 as pilot in command · 110 in the last 90 days · 40 in the last 30 days · 2 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 52° at 6 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 77 °F, dew point 52 °F
- Altimeter
- 29.90 inHg
- Observed at
- GTF
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.