NTSB Identification: NYC91FA178.
The docket is stored on NTSB microfiche number 45310.
Accident occurred Friday, July 12, 1991 in YARMOUTH, MA
Probable Cause Approval Date: 04/14/1992
Aircraft: PIPER PA-32RT-300T, registration: N36272
Injuries: 2 Fatal.

NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.

AFTER RECEIVING CLEARANCE TO LAND, THE PILOT CALLED THAT HE WAS IN TROUBLE AND WAS GOING DOWN. WITNESSES SAW THE AIRPLANE AT A LOW ALTITUDE, AND HEARD THE ENGINE SPUTTERING AND THEN QUIT. THE LEFT WING STRUCK A TREE; THE AIRPLANE IMPACTED THE GROUND AND WAS COMPLETELY DESTROYED BY THE POST CRASH FIRE. ENGINE TEARDOWN REVEALED THAT THE CYLINDER #1 FUEL INJECTOR LINE HAD FAILED AT THE OUTER DIAMETER (OD) SURFACE AT THE MANIFOLD END NEAR THE B-NUT FITTING. METALLURGICAL EXAMINATION INDICATED THAT THE SEPARATION WAS DUE TO FATIGUE CRACKING THAT ORIGINATED AT THE OD SURFACE OF THE TUBE AT THE EDGE WITH THE BRAZED FILLER METAL. INTERGRANULAR CORROSION WAS OBSERVED AT THE FRACTURE ORIGIN WHICH OCCURRED DURING MANUFACTURE, WHEN THE LINE WAS SENSITIZED NEAR THE BRAZING JOINT. THERE WAS NO EVIDENCE OF CLAMPING OF THE TUBE AT MIDPOINT PER THE ENGINEERING DRAWING.

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

THE FAILURE OF THE NUMBER ONE CYLINDER FUEL INJECTOR LINE DUE TO FATIGUE CRACKING INDUCED BY CORROSION AND PROPAGATED BY CYCLIC LOADING WHICH RESULTED IN A TOTAL LOSS OF ENGINE POWER. THE CORROSION WAS DUE TO THE MANUFACTURER'S PROCESS OF BRAZING THE METAL JOINT, AND THE CYCLIC LOADING WAS DUE TO THE ABSENCE OF A CLAMP TO MINIMIZE THE EFFECT OF VIBRATION. A CONTIBUTING FACTOR WAS THE LACK OF SUITABLE TERRAIN DURING THE SUBSEQUENT FORCED LANDING.

Index for Jul1991 | Index of months