NTSB · Safety Recommendation
Safety Recommendation A-76-117
Recommendation
REVIEW APPLICABILITY OF AD 72-21-07 FOR PA 23 MODELS OTHER THAN THE -250 AND EXTEND THE APPLICABILITY AS NECESSARY. (URGENT)
Safety Issue and Context
ON MARCH 28, 1976, NEAR PULLMAN, WASHINGTON, A PIPER PA23-250 C (N6199Y) STRUCK THE GROUND IN A HIGH SPEED SPIRAL. DURING ITS INVESTIGATION OF THE CRASH, THE NATIONAL TRANSPORTATION SAFETY BOARD DISCOVERED THAT A MAJOR STRUCTURAL ALTERATION HAD BEEN APPROVED AND ACCOMPLISHED WITHOUT PROPER ENGINEERING EVALUATION. THE MAJOR ALTERATION WAS AN EXTENSION OF THE FUSELAGE NOSE BY INSTALLING P/N 32958-00--SECTION ASSEMBLY - FUSELAGE NOSE. APPROVAL FOR THE INSTALLATION WAS GIVEN BY THE GENERAL AVIATION DISTRICT OFFICE (GADO)ON A "MAJOR REPAIR AND ALTERATION" FAA FORM 337, DATED MARCH 14, 1975.
THE BASIS FOR APPROVAL WAS THE PIPER SERVICE MANUAL.CHANGES IN WEIGHT WERE LISTED AND A STATEMENT THAT THE WEIGHT AND BALANCE DATA HAD BEEN REVISED WAS INCLUDED.
Response History
November 9, 1976 · Recipient Response · FAA
WE HAVE REVIEWED AD 72-21-07 AND CONSIDER IT APPLICABLE TO PIPER PA-23-250 AIRPLANES ONLY. WE WOULD REQUIRE SEPARATE ASSESSMENTS, SUBSTANTIATION, INCLUDING FLIGHT TESTING, FOR APPROVAL OF LONG NOSE MODIFICATIONS TO OTHER MODELS.