# Accident 19991010028989A: Piper PA18150, Granite, OK, October 10, 1999

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: October 10, 1999, 19:05 local time
- Place: Granite, OK
- Airport: Twin Lakes Ranch Airport
- Damage: Destroyed
- Phase of flight: To Init Climb(1st Pwr Reduct)
- Operating rules: General operating rules (Part 91)
- Location: 34.9596° N, 99.3701° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=34.9596&lon=-99.3701&mi=10
- Aircraft: N4473A, a cancelled registration (https://openairdocs.org/deregistered/N4473A-2013-08-13) (OpenAirDocs)
- Registry model: Piper PA-18-150 (registry code 7101828, https://openairdocs.org/model/piper-pa-18-150) (OpenAirDocs)
- Registry engine: Lycoming 0-320 series (registry code 41508, https://openairdocs.org/engine/lycoming-0-320-series) (OpenAirDocs)
- Reported make and model: PIPER PA18150
- Reported engine: LYC O320*
- Fatal injuries: 0
- Pilot flight hours: 1,200 total, 150 in this make and model, 35 in the last 90 days
- NTSB investigation: [NTSB FTW00LA010](https://openairdocs.org/ntsb/FTW00LA010) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19991010028989A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

(.19) ON OCTOBER 10, 1999, AT 1759 CENTRAL DAYLIGHT TIME, A PIPER PA-18-150, N4473A, SUSTAINED SUBSTANTIAL DAMAGE DURING AN ABORTED TAKEOFF FROM A PRIVATE GRASS AIRSTRIP NEAR GRANITE, OKLAHOMA. THE AIRCRAFT WAS OWNED AND OPERATED BY GREAT PLAINS AVIATION LLC, GRANITE, OKLAHOMA, UNDER 14 CODE OF FEDERAL REGULATIONS PART 91. THE PRIVATE PILOT AND THE PASSENGER RECEIVED SERIOUS INJURIES. VISUAL METEOROLOGICAL CONDITIONS PREVAILED FOR THE LOCAL PERSONAL FLIGHT, AND A FLIGHT PLAN WAS NOT FILED. THE FLIGHT WAS ORIGINATING AT THE TIME OF THE ACCIDENT. LOCAL AUTHORITIES AND THE PASSENGER REPORTED THAT THE AIRPLANE HIT THE GROUND AND ROLLED. FAA INSPECTORS, WHO RESPONDED TO THE SITE, FOUND CONTINUITY TO THE FLIGHT CONTROL SURFACES. (-23)DURING A NORTHBOUND TAKEOFF FROM PRIVATE OWNED GRASS AIRSTRIP THE AIRCRAFT BECAME UNCONTROLLABLE JUST AFTER LIFT OFF.  IT MADE A SHARP LEFT TURN AND THE LEFT WING IMPACTED THE GROUND CAUSING THE AIRCRAFT TO CARTWHEEL, COMING TO REST FACING SOUTH APPROXIMATELY 100 FEET FROM THE END OF THE AIRSTRIP.  THERE WAS NO POST ACCIDENT FIRE.                                                                                                                                  (.4)THE AIRPLANE WAS DESTROYED UPON IMPACT WITH TERRAIN FOLLOWING A LOSS OF CONTROL DURING THE TAKEOFF/INITIAL CLIMB. SEVERE CORROSION WAS FOUND AT TWO STRUCTURAL TUBE CLUSTERS (ONE WITH A WINDSHIELD PILLAR) LOCATED DIRECTLY BELOW THE RIGHT WING FORWARD AND AFT ATTACH FITTINGS. THE PORTION OF THE FORWARD STRUCTURE AVAILABLE FOR CARRYING LOADS PRIOR TO THE ACCIDENT WAS LESS THAN 30% OF THE CIRCUMFERENCE OF THE PILLAR TUBE.  DEFORMATION ASSOCIATED WITH THE SEPARATION OF THE PILLAR TUBE INDICATES THAT THE PILLAR FAILED UNDER COMPRESSION LOADS.  THE MANUFACTURER'S REPRESENTATIVE STATED THAT THE 'WINDSHIELD PILLAR IS NORMALLY SUBJECTED TO A TENSILE LOAD DURING FLIGHT.'  IT IS POSSIBLE THAT COMPRESSION LOADS GENERATED DURING THE TAKEOFF ROLL LED TO A COMPRESSION FAILURE OF THE PILLAR.  THIS FAILURE WOULD HAVE CHANGED THE LIFT CHARACTERISTICS OF THE WING SINCE THE SEPARATION POINT WAS DIRECTLY BELOW THE RIGHT WING FORWARD ATTACH FITTING.  THE MOST RECENT ANNUAL INSPECTION WAS PERFORMED IN JANUARY 1999; THE MAINTENANCE ENTRY FOR THE ANNUAL STATED, IN PART, 'TREATED STEEL TUBING AS REQUIRED.'  IN JUNE 1999, A MAJOR REPAIR WAS MADE TO A TUBE CLUSTER IN THE AFT FUSELAGE AREA 'DUE TO EXTERNAL  RUST THROUGH FROM PAST ACID SPILL.'

## 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 FTW00LA010](https://openairdocs.org/ntsb/FTW00LA010), Oct 11, 1999: Piper PA-18-150 (N4473A), Granite, OK, substantial damage. Probable cause: Corrosion failure of the fuselage support tubing below the right wing forward attach fitting due to inadequate maintenance.

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.

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