# Accident 20140925019389A: William M Oprendek PITTS S1S, Sedona, AZ, September 25, 2014 - Type: FAA accident report (Accident/Incident Data System), as reported - Date: September 25, 2014, 08:30 local time - Place: Sedona, AZ - Airport: Sedona - Damage: Substantial damage - Phase of flight: Landing: Touchdown - Operating rules: General operating rules (Part 91) - Location: 34.8486° N, 111.7883° W: From the FAA - Nearby events: https://openairdocs.org/map.md?lat=34.8486&lon=-111.7883&mi=10 - Aircraft: N93DB, a cancelled registration (https://openairdocs.org/deregistered/N93DB-2017-01-05) (OpenAirDocs) - Registry model: William M Oprendek PITTS S1S (registry code 05632LV, https://openairdocs.org/model/william-m-oprendek-pitts-s1s) (OpenAirDocs) - Registry engine: Superior IO-360 series (registry code 59251, https://openairdocs.org/engine/superior-io-360-series) (OpenAirDocs) - Reported make and model: WILLIAM M OPRENDEK PITTS S1S - Reported engine: SUPERIOR IO-360 - People aboard: 1 - Fatal injuries: 0 - Other injuries: 0 - Pilot certificates: Airline transport, flight instructor - Pilot flight hours: 31,300 total, 690 in this make and model, 14 in the last 90 days - NTSB investigation: [NTSB WPR14CA390](https://openairdocs.org/ntsb/WPR14CA390) (OpenAirDocs) - FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/) - Page: https://openairdocs.org/incident/20140925019389A ## Narrative As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^. THE AIRCRAFT WAS CONDUCTING A PHASE 1 FLIGHT FOR EXPERIMENTAL AMATEUR BUILT OPERATING LIMITATIONS OUT OF THE SEDONA AIRPORT AREA. THE PILOT STATED THE AIRCRAFT HAD HANDLED NORMALLY DURING TAXI AND TAKE OFF ROLL. AS PART OF THIS PHASE 1 FLIGHT REGIME THE PILOT CONDUCTED AEROBATIC MANEUVERS TO INCLUDE A 4-POINT ROLL. HE DESCRIBED THIS AS A MANEUVER WHICH REQUIRES RAPID STOP-TO-STOP RUDDER INPUT. THE PILOT STATED THAT HE INITIATED A SLIP ON FINAL APPROACH WHICH WAS THE NORMAL PROCEDURE FOR LANDING THIS AIRCRAFT. ALL WAS PROCEEDING NORMALLY AS THE AIRCRAFT TOUCHED DOWN ON THE MAIN GEAR. WHEN THE TAIL WHEEL LOWERED AND TOUCHED DOWN THE AIRCRAFT MADE A VIOLENT 90 DEGREE TURN/YAW TO THE RIGHT. THE PILOT ATTEMPTED TO APPLY LEFT RUDDER AND BRAKE, BUT THE AIRCRAFT DEPARTED THE RUNWAY TO THE RIGHT AND DUG INTO SOFT DIRT OFF THE SIDE OF THE RUNWAY. THE RIGHT GEAR DUG INTO THE DIRT AND THE AIRCRAFT CARTWHEELED. THE PILOT ATTEMPTED TO STOP THE ROLL BY APPLYING LEFT AILERON AND THE AIRCRAFT ROLLED LEVEL. THE AIRCRAFT THEN TRAVELED DOWN A 5 FOOT EMBANKMENT AND CAME TO A STOP AFTER THE PROP & ENGINE STRUCK THE GROUND. THE PILOT SHUT ALL POWER AND FUEL OFF TO THE AIRCRAFT AND EXITED THE AIRCRAFT. THE AIRCRAFT SUSTAINED DAMAGE TO THE RIGHT UPPER AND LOWER WING TIP, THE UPPER RIGHT HAND WING SPAR WAS CRACKED, THE LEFT LOWER WING TIP AND LOWER AILERON WERE DAMAGED, LEFT HAND LANDING GEAR BENT, DAMAGE TO THE FAIRINGS & WHEELPANTS, DAMAGE TO THE FUSELAGE FRAME IN THE LANDING GEAR ATTACH AREA, AND POTENTIAL DAMAGE TO THE FUEL TANK AREA. THE PROP WAS DESTROYED AND THE ENGINE ENCOUNTERED SUDDEN STOPPAGE AS WELL. THE PILOT WALKED AWAY FROM THE AIRCRAFT WITH NO INJURIES. HE STATED THAT HE WAS WEARING THE 5 POINT SEATBELT AND HELMET WHICH HE ALWAYS WEARS. HE SAID HE COULD REMEMBER RATCHETING THE SEATBELT TIGHT PRIOR TO LANDING. THE PILOT IS AN EXPERIENCED PILOT WITH A BACKGROUND IN COMPETITION AEROBATIC FLYING. THIS AIRCRAFT WAS HIS THIRD PITTS WHICH HE HAD BUILT AND FLOWN FROM THE FIRST FLIGHT. HE EXPLAINED THAT PRIOR TO THIS FLIGHT THIS AIRCRAFT HAD APPEARED NORMAL DURING PREFLIGHT AND HAD HANDLED NORMALLY THROUGHOUT THE IN-FLIGHT PORTION OF OPERATION. HE STATES THIS AIRCRAFT WAS THE BEST HANDLING PITTS AIRCRAFT HE HAD BUILT AND FLOWN. THIS LANDING WAS APPROXIMATELY THE 90TH ON THIS AIRCRAFT TAILWHEEL ASSEMBLY. THE TAILWHEEL WAS OBSERVED TO BE COCKED 90 DEGREES TO THE RIGHT AT THE ACCIDENT SCENE. WHEN THE AIRCRAFT WAS MOVED IT WAS NOTED THE TAILWHEEL ASSEMBLY DID NOT RETURN TO CENTER AND APPEARED TO BE FROZEN IN THE COCKED POSITION. THE RUDDER TO TAILWHEEL ATTACH CABLE/CHAIN WAS ALSO BROKEN. IT IS UNCLEAR WHETHER THE CABLE/CHAIN BROKE AS A RESULT OF THE ACCIDENT OR WAS BROKEN PRIOR TO LANDING. THE PILOT/BUILDER ASKED A LOCAL MECHANIC/IA TO ASSIST BY INSPECTING & DISASSEMBLING THE TAILWHEEL ASSEMBLY. IT TOOK CONSIDERABLE EFFORT TO DISASSEMBLE THE TAILWHEEL UNIT AS THERE WAS SOMETHING JAMMED IN THE ASSEMBLY. IT WAS DETERMINED THAT THE WHEEL CENTERING SPRING HAD JAMMED BETWEEN THE WHEEL FORK POST AND THE HOUSING ASSY. CAUSING THE WHOLE UNIT TO JAMB IN POSITION. THE PILOT BELIEVES THAT THE TAILWHEEL JAMMED INTO POSITION 90 DEGREE TO CENTERLINE DURING THE AEROBATIC MANEUVERS HE HAD CONDUCTED DURING THE FLIGHT. ## The NTSB's investigation of this event (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB WPR14CA390](https://openairdocs.org/ntsb/WPR14CA390), Sep 25, 2014: William M Oprendek Pitts S1S (N93DB), Sedona, AZ, substantial damage. Probable cause: Failure of the tailwheel steering assembly during maneuvering flight, which resulted in a loss of directional control during the landing roll. From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.