NTSB Identification: DEN86LA239.
The docket is stored on NTSB microfiche number 31369.
Accident occurred Tuesday, August 26, 1986 in GRAND FORKS, ND
Aircraft: PIPER PA-23E-250, registration: N900TS
Injuries: 6 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

THE ACFT WAS EN ROUTE FROM FLIN FLON AIRPORT, MANITOBA, CD, TO MASON CITY, IA, AND HAD STOPPED AT GRAND FORKS, ND, FOR FUEL AND TO CLEAR CUSTOMS. DURING TAXI FOR TAKEOFF, THE ACFT STRUCK A 1-INCH CONCRETE LIP ON THE RAMP AND THE RIGHT MAIN LANDING GEAR COLLAPSED. POST ACCIDENT EXAMINATION REVEALED THE ACTUATOR ROD END WAS BENT AND ONE OF FOUR SPRINGS ON THE OVERCENTER CAM DEVICE WAS DETACHED FROM ITS PROPER ATTACH POINT AND WAS EXCESSIVELY STRETCHED. WITH THE ACFT ON JACKS THE SPRING WAS REATTACHED AND THE GEAR WAS EXTENDED, TRAPPING THE SPRING BETWEEN THE DOWNLOCK SWITCH AND THE DOWNLOCK OVERCENTER MECHANISM. WITH SOME WEIGHT APPLIED TO THE LANDING GEAR, A FIRM UPWARD PRESSURE WAS APPLIED TO THE OVERCENTER DEVICE AND THE RIGHT MAIN LANDING GEAR RETRACTED. FURTHER TESTS REVEALED THAT THE LANDING GEAR SELECTOR HANDLE DID NOT ALWAYS CATCH THE SAFETY LATCH WHEN PLACED IN THE NEUTRAL POSITION, AND THAT IT WAS POSSIBLE FOR THE SELECTOR TO GO FROM DOWN TO UP WITHOUT TRIGGERING THE LATCH.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

LANDING GEAR,NORMAL RETRACTION/EXTENSION ASSEMBLY..BENT

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

LANDING GEAR,NORMAL RETRACTION/EXTENSION ASSEMBLY..DISCONNECTED


Contributing Factors

AIRPORT FACILITIES,RUNWAY/LANDING AREA CONDITION..ROUGH/UNEVEN

Index for Aug1986 | Index of months