- Date
- May 7, 2001, 19:56 local (May 8, 2001, 03:56 UTC)
- Place
- Fairbanks, AK
- Injuries
- 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N3143ACessna 170B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report February 20, 2002
- Report
- Approved by Office Director
- NTSB office
- Alaska Regional Office
- Parties
- FAA-AL-FAI FSDO 01
- FAA report
- 20010507007849A
- Case key
- 52229
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
A failure of the tailwheel spring assembly due to fatigue during touch and go landings. A factor in the accident was an inadequate annual inspection by maintenance personnel.
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
The commercial certificated pilot/flight instructor was conducting a local area instructional flight with the student pilot/owner of the airplane. The flight instructor reported that he was doing wheel landings with the student to a gravel runway. During the touch down on the third or fourth landing, the tailwheel assembly suddenly broke off. An FAA airworthiness inspector examined the airplane after the accident and found a preexisting crack in the tailwheel spring assembly that was about 1/16 inch deep, and about 1/2 inch long. The spring failed at the crack. When the tail wheel departed the airplane, it struck the bottom of the rudder, and the rudder trim tab. The bottom and aft portion of the rudder assembly was torn open. The spring assembly had accrued 126 hours, and 65 hours since the last annual inspection.
Factual narrative
On May 7, 2001, at 1956 Alaska daylight time, a wheel-equipped Cessna 170B airplane, N3143A, sustained substantial damage during landing at the Fairbanks International Airport, Fairbanks, Alaska. The airplane was being operated as a visual flight rules (VFR) local area instructional flight when the accident occurred. The airplane was operated by the student pilot/owner. The commercial certificated pilot/flight instructor, and the student pilot, were not injured. Visual meteorological conditions prevailed. The flight originated at the Fairbanks International Airport at 1917.
During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on May 9, 2001, the flight instructor reported that he was seated in the right seat, and was conducting wheel landings with the student on the ski strip, runway 19, at Fairbanks. During the touchdown on the third or fourth landing, the tailwheel assembly suddenly broke off.
A Federal Aviation Administration (FAA) airworthiness inspector, Fairbanks Flight Standards District Office (FSDO), examined the airplane after the accident. He reported he found a preexisting crack in the tailwheel spring assembly that was about 1/16 inch deep, and about 1/2 inch long. He said the spring failed at the crack, and when the tailwheel departed the airplane, it struck the bottom of the rudder, and the rudder trim tab. The bottom and aft portion of the rudder assembly was torn open.
In the Pilot/Operator Report (NTSB form 6120.1/2) submitted by the student pilot/owner, the owner indicated the tailwheel spring had a total time of 162 hours. The 6120.1/2 report noted an annual inspection was conducted on November 6, 2000, 65 hours before the accident.
Aircraft
- Registration
- N3143A
- Reported as
- Cessna 170B
- Category
- Airplane
- Serial number
- 25787
- Airframe hours
- 4,904
- Engine
- Continental C-145, 145 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Instructional · Part 91
- Registered owner
- Cordell T. Gray
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · November 6, 2000 · 65 hours before
- Departed
- PAFA · Fairbanks, AK
- Airport
- PAFA · Fairbanks International, runway 19, 3,980 × 75 ft, gravel
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 · 2
As NTSB recorded them. NTSB leaves out names.
- Role
- Flight instructor
- Age
- 62
- Injuries
- None
- Certificates
- Commercial, Flight instructor
- Airplane ratings
- Multi-engine land, Single-engine sea, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Last flight review
- May 9, 2000
- Seat
- Right
- Flight hours
- 4,591 total · 210 in this make and model · 3,891 as pilot in command · 56 in the last 90 days · 48 in the last 30 days · 6 in the last 24 hours
- Role
- Student pilot
- Age
- 39
- Injuries
- None
- Certificate
- Student
- Medical
- Class 3, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 83 total · 83 in this make and model · 28 as pilot in command · 39 in the last 90 days · 17 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 184° at 3 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- 5,500 ft broken
- Temperature
- 45 °F, dew point 30 °F
- Altimeter
- 29.63 inHg
- Observed at
- PAFA
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.