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Safety Recommendation Details

Safety Recommendation A-79-007
Details
Synopsis: ON AUGUST 30, 1978, A PIPER MODEL 31-350 AIRCRAFT, N44LV, CRASHED SHORTLY AFTER TAKEOFF FROM LAS VEGAS, NEVADA; THE 10 PERSONS ON BOARD WERE KILLED. WITNESSES SAW THE AIRCRAFT REACH A STEEP NOSE-HIGH ATTITUDE AFTER TAKEOFF BEFORE IT FELL OFF ON THE RIGHT WING, REVERSED DIRECTION, AND DOVE TOWARD THE GROUND. THE AIRCRAFT HAD ACHIEVED A NEARLY FLAT ATTITUDE IN AN APPARENT ATTEMPT TO RECOVER WHEN IT STRUCK THE GROUND WITH HIGH VERTICAL FORCES.
Recommendation: ISSUE AN AIRWORTHINESS DIRECTIVE TO REQUIRE THE IMMEDIATE INSPECTION OF ALL PIPER AIRCRAFT EQUIPPED WITH CONTROL STOP BOLT INSTALLATIONS WHERE EXTENSION OF THE STOP BOLT CAN LIMIT CONTROL SURFACE TRAVEL TO DETERMINE IF STOP BOLT POSITION OR JAM NUT TORQUE HAS CHANGED. REQUIRE READJUSTMENT OF THE STOP BOLT AND RETORQUING OF THE JAM NUT AS NECESSARY. REQUIRE THAT THE STOP BOLT INSTALLATION BE MODIFIED TO INCLUDE SAFETY WIRE OR SOME OTHER POSITIVE NONFRICTION MEANS OF PREVENTING ROTATION OF THE STOP BOLT DURING THE APPLICATION OF VIBRATORY LOADS. (URGENT)
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Aviation
Location: Las Vegas, NV, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: 80075
Accident Reports: Las Vegas Airlines, Piper PA-31-350, N44LV
Report #: AAR-79-08
Accident Date: 8/30/1978
Issue Date: 3/5/1979
Date Closed: 5/24/1984
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Alternate Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 5/24/1984
Response: The events that have taken place relative to this recommendationsince august 30, 1978, are: 1. General aviation airworthiness alerts-6/79 (alert no. 11) under maintenance notes contained a discussion of the problem. 2. General aviation airworthiness alerts-11/79 (alert no. 16) listedthree incidents related to the stop bolt issue. In two cases, no elevator stop bolt discrepancies were found. In one, during a 100-hour inspection, the elevator bottom bolt lock nut was loose and the bolt head was missing. 3. A general aviation airworthiness alert of unknown date included a dis- cussion of the stop bolt problem and advised maintenance personnel, operators, and pilots to check control surface travel (1979 information system statistics quoted). 4. July 2, 1979, ad-79-12-02 became effective stating:compliance required with the next 25 hrs time in service after the effective date . . to prevent the possible restriction of elevator surface tra- vel . . inspect and fix stop bolts. 5. 1980-81 piper current production airplanes incorporate a redundant safety wire feature on elevator stop bolts. 6. February 10, 1981, piper pa-31 commuter crashed at prescott, az with a finding that the elevator down stop bolt and backed out 8/9 threads.. . Your efforts are appreciated.

From: FAA
To: NTSB
Date: 11/28/1983
Response: FAA LETTER: "ON JUNE 21, 1979, THE FAA ISSUED AIRWORTHINESS DIRECTIVE (AD) 79-12-02. THIS AD REQUIRED THE INSPECTION OF THE ELEVATOR STOP BOLTS, VERIFICATION OF PROPER ELEVATOR TRAVEL, TORQUING OF ELEVATOR STOP BOLT LOCK NUTS, AND PAINTING OR INSTALLATION OF A SLIP STRIP OR TORQUE SEAL. A REVIEW OF THE FAA'S SERVICE DIFFICULTY REPORTING SYSTEM INDICATES NO REPORTS HAVE BEEN RECEIVED AFTER JULY 6, 1979, INDICATING THE PRESENT AD HAS BEEN EFFECTIVE. FOR THE BOARD'S FURTHER INFORMATION, PIPER AIRCRAFT CORPORATION ISSUED PIPER SERVICE LETTER NO. 916 (COPY ENCLOSED), DATED JULY 17, 1981, WHICH PROVIDES INFORMATION FOR IMPROVED SECURITY OF THE ELEVATOR STOP BOLT."

From: NTSB
To: FAA
Date: 7/30/1981
Response: In response to safety recommendation a-79-7 we note that piper aircraft corporation has introduced a production change in the pa-31 seriesto provide for positive locking in the stop bolt and lock nut by safety wiring the bolt and nut to the airplane structure. We also not that piper is preparing a service bulletin recommending safety wire installations on airplanes in the field. Pending the issuance of the service bulletin and the faa's further notification of completed action, a-79-7 will be main- tained in an open--acceptable alternate action status.

From: FAA
To: NTSB
Date: 6/15/1981
Response: FEDERAL AVIATION ADMINISTRATION LTR: AS CORRECTLY STATED IN YOUR LETTER OF APRIL 17, 1981, PIPER AIRCRAFT CORPORATION HAS INCORPORATED A PRODUCTION CHANGE IN THE PA-31 SERIES THAT PROVIDES FOR POSITIVE LOCKING OF THE STOP BOLT AND LOCK NUT BY SAFETY WIRING THE BOLT AND NUT TO AIRPLANE STRUCTURE. PIPER IS ALSO PREPARING A SERVICE BULLETIN RECOMMENDING SAFETY WIRE INSTALLATION ON AIRPLANES IN THE FIELD. THE FAA WILL EVALUATE THE SERVICE BULLETIN WHEN ISSUED TO DETERMINE WHAT FURTHER ACTION MIGHT BE APPROPRIATE. WE WILL ADVISE THE BOARD OF OUR EVALUATION AND PROVIDE A COPY OF THE SERVICE BULLETIN WHEN ISSUED.

From: NTSB
To: FAA
Date: 4/17/1981
Response: . . . however, we are now investigating a similar type accident.A piper pa-31 navajo chieftain crashed on takeoff at prescott, arizona, on february 10, 1081. After the gear was retracted, the nose pitched up and a still occurred. Prior to the pilot reducing power, he and the right front passenger vainly tried to push the yoke forward to recover from the stall. Investigation revealed that the elevator down- stop bolt, that limits the down elevator travel, had backed out eight threads. The requirements of the ad and been complied with on may 10, 1979. This recent accident has added to our concern in that a positive locking method is not utilized to prevent such occurrences. We request a further response to our two recommendations and to be informed of the results of the faa's maintenance analysis center review.

From: NTSB
To: FAA
Date: 7/3/1979
Response: Recommendation a-79-7 called upon the faa to issue an ad requiring immediate inspections of all piper aircraft equipped with simi- lar control stop bolts, and modifications of such installations with either safety wiring or another positive nonfriction means to prevent stop bolt rotation under vibration. We note that the faa is in the process of issuing an ad for the pa-31. We also note that the faa is reviewing the problem to determine whether all aircraft equipped with the stop bolt/lock nuts should be inspected. Pending the faa's conclusive action, a-79-7 is being maintained in an 'open--acceptable action status.

From: FAA
To: NTSB
Date: 6/7/1979
Response: FAA LTR: A TELEPHONIC DIRECTED SAFETY INVESTIGATION (DSI) TO INSPECT ELEVATOR STOP BOLTS AND ELEVATOR SURFACE TRAVEL ON PA-31 AIRPLANES RESULTED IN ONE REPORT OF A LOOSE BOLT. AS A RESULT OF THIS FINDING AN AIRWORTHINESS DIRECTIVE IS BEING PREPARED. THIS AD WILL REQUIRE A CHECK OF ELEVATOR TRAVEL, INSPECTION OF THE CONDITION OF THE STOP BOLT/LOCK NUTS. AT THIS TIME, WE DO NOT HAVE SUFFICIENT EVIDENCE OF UNSATISFACTORY PERFORMANCE TO JUSTIFY A REGULATORY REQUIREMENT TO MODIFY OR REDESIGN STOP BOLT/ LOCK NUT CONTROL SURFACE STOPS ON OTHER MAKES AND MODELS OF AIRCRAFT. WE ARE CONDUCTING A REVIEW OF SERVICE EXPERIENCE AT THE FEDERAL AVIATION ADMINISTRATION MAINTENANCE ANALYSIS CENTER.