- Date
- September 25, 2014, 08:30 local (15:30 UTC)
- Place
- Sedona, AZ
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N93DBWilliam M Oprendek Pitts S1S
- Defining event
- Maneuvering: Sys/Comp malf/fail (non-power)
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 5, 2014
- Report
- Approved by Office Director
- NTSB office
- Western Pacific Region
- Parties
- Federal Aviation Administration FSDO
- FAA report
- 20140925019389A
- Case key
- 90158
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
Failure of the tailwheel steering assembly during maneuvering flight, which resulted in a loss of directional control during the landing roll.
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/builder of the experimental amateur-built, tailwheel-equipped airplane had just completed a flight as part of phase one flight testing. He reported an uneventful approach to landing, with the main landing gear touching down first. However, as soon as the tailwheel made contact with the runway, the airplane yawed violently to the right. The pilot applied full left rudder and brake control input, but the airplane did not respond, and departed the runway descending down an embankment. The airplane sustained substantial damage to the upper wing spar and fuselage structure at the landing gear attach points. Postaccident examination revealed that the tailwheel was locked 90 degrees to the right. The tailwheel assembly was disassembled, and the steering arm cam spring appeared jammed between the shaft and housing. The inner surface of the housing exhibited scoring marks, consistent with a pre-existing failure of the spring. The pilot reported that he had purchased the tailwheel assembly used, and that he did not have any records indicating its manufacturer or serial number.
Factual narrative
The pilot/builder of the experimental amateur-built, tailwheel-equipped airplane had just completed a flight as part of phase one flight testing. He reported an uneventful approach to landing, with the main landing gear touching down first. However, as soon as the tailwheel made contact with the runway, the airplane yawed violently to the right. The pilot applied full left rudder and brake control input, but the airplane did not respond, and departed the runway descending down an embankment. The airplane sustained substantial damage to the upper wing spar and fuselage structure at the landing gear attach points. Postaccident examination revealed that the tailwheel was locked 90 degrees to the right. The tailwheel assembly was disassembled, and the steering arm cam spring appeared jammed between the shaft and housing. The inner surface of the housing exhibited scoring marks, consistent with a pre-existing failure of the spring. The pilot reported that he had purchased the tailwheel assembly used, and that he did not have any records indicating its manufacturer or serial number.
Aircraft
- Registration
- N93DB
- Reported as
- William M Oprendek Pitts S1S (NO SERIES)
- Category
- Airplane, amateur-built
- Serial number
- PITTS S1SS-3
- Built
- 2013
- Airframe hours
- 53.1
- Engine
- Superior XP-IO-360-E1D, 185 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Condition · July 3, 2014 · 43.2 hours before
- Departed
- SEZ · Sedona, AZ
- Destination
- SEZ · Sedona, AZ
- Airport
- SEZ · Sedona, runway 03, 5,132 × 100 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
- 70
- Injuries
- None
- Certificates
- Commercial, Flight engineer, Airline transport
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 3, Waiver time limited special
- Last flight review
- June 12, 2013
- Seat
- Single
- Restraint
- 5-point
- Flight hours
- 31,293 total · 690 in this make and model · 23,909 as pilot in command · 14.1 in the last 90 days · 3.9 in the last 30 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 80° at 3 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 75 °F, dew point 48 °F
- Altimeter
- 30.22 inHg
- Observed at
- KSEZ
Docket · 6
The files NTSB released with the investigation on November 25, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.9 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.