Skip Ribbon Commands
Skip to main content
Safety Recommendation Details

Safety Recommendation A-85-001
Details
Synopsis: ON DECEMBER 6, 1984, A PROVINCETOWN-BOSTON AIRLINES, INC., EMBRAER BANDEIRANTE (EMB-110), N96PB, OPERATING AS FLIGHT 1039, CRASHED SHORTLY AFTER TAKEOFF FROM THE JACKSONVILLE INTERNATIONAL AIRPORT, JACKSONVILLE, FLORIDA. ALL 13 PERSONS ON BOARD WERE KILLED, AND THE AIRPLANE WAS DESTROYED. THE NATIONAL TRANSPORTATION SAFETY BOARD'S CONTINUING INVESTIGATION HAS DISCLOSED THAT THE AIRPLANE'S ELEVATORS AND HORIZONTAL STABILIZER SEPARATED IN FLIGHT, RENDERING THE AIRPLANE UNCONTROLLABLE. EVIDENCE TO DATE INDICATES THAT THE HORIZONTAL STABILIZER SEPARATED FROM THE FUSELAGE AT BULKHEAD 33 ALONG THE TOP RIGHTHAND CORNER OF THE STABILIZER ATTACHMENT FITTING. THIS AREA OF THE BULKHEAD IS SUPPORTED BY C-SHAPED, P/N 4A-1411-08, AND U-SHAPED, P/N 4A-1411-07-17, CHANNELS WHICH ARE RIVETED TOGETHER. THE FUNCTION OF THESE CHANNELS APPEARS TO BE TO TRANSFER THE AFT AND DOWNWARD LOADS ON THE FORWARD ATTACHMENT POINTS OF THE STABILIZER TO THE MONOCOQUE STRUCTURE THROUGH LONGERONS AND THE OUTER FUSELAGE SKIN.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: ISSUE AN AIRWORTHINESS DIRECTIVE (AD) TO REQUIRE, THAT BEFORE FURTHER COMMERCIAL OPERATION IN THE UNITED STATES, THE HORIZONTAL STABILIZER ATTACHMENT OF EMB-110P1 AND -110P2 MODEL AIRPLANES NOT PREVIOUSLY MODIFIED IN ACCORDANCE WITH AD 83-14-09, AMENDMENT 39-4527, PARAGRAPH (D) OR (E), BE INSPECTED USING AN IMPROVED INSPECTION PROCEDURE TO ENHANCE DETECTION OF LOOSE OR SHEARED RIVETS, PARTICULARLY WHERE BULKHEAD 33 TRANSMITS THE LOADS FROM THE STABLIZIER FORWARD ATTACHMENT TO THE FUSELAGE MONOCOQUE STRUCTURE. THE INSPECTION PROCEDURE SHOULD REQUIRE REMOVAL OF CONTROLS AS NEEDED FOR ACCESS TO RIVETED JOINTS AND APPLICATION OF EXTERNAL LOADS TO DETECT RELATIVE MOVEMENT BETWEEN STRUCTURAL MEMBERS. THE AD SHOULD REQUIRE THAT DEFICIENCIES DETECTED DURING INSPECTION BE REPORTED TO THE FAA AND THAT THEY BE CORRECTED IN ACCORDANCE WITH AN APPROVED PROCEDURE BEFORE FURTHER FLIGHT. (URGENT)
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Aviation
Location: JACKSONVILLE, FL, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA85AA004
Accident Reports: Provincetown-Boston Airlines Flight 1039, Embraer Bandeirante, EMB-110P1, N96PB
Report #: AAR-86-04
Accident Date: 12/6/1984
Issue Date: 1/8/1985
Date Closed: 8/3/1987
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Alternate Action)
Keyword(s):

Safety Recommendation History
From: FAA
To: NTSB
Date: 8/3/1987
Response:

From: NTSB
To: FAA
Date: 6/24/1986
Response: In response to Safety Recommendation A-85-1 the FAA issued Emergency Airworthiness Directive 85-01-51 on January 10, 1985, which required a comprehensive inspection of the EMB-110P1 and 110P2 model airplanes addressed in the above recommendations. As a result, the Safety Board classified Safety Recommendation A-85-1 as "Closed-- Acceptable Alternate Action."

From: FAA
To: NTSB
Date: 1/11/1985
Response: FAA LTR: TELEGRAPHIC AIRWORTHINESS DIRECTIVE T85-01-51 WAS ISSUED ON JANUARY 10 TO REQUIRE ALL U.S. OPERATORS OF EMBRAER MODELS EMB-110P1 AND -110P2 AIRPLANES TO COMPLETE THE INSPECTIONS ADDRESSED BY RECOMMENDATION A-85-1 WITHIN THE NEXT 18 HOURS TIME IN SERVICE. ON JANUARY 9 THE BRAZILIAN AIRWORTHINESS AUTHORITY (CTA) CONFIRMED BY TELEGRAM THAT IN MARCH 1983, EMBRAER HAD COMPLETED STRUCTURE TESTS WHICH SUBSTANTIATED THE RESIDUAL STRENGTH OF THE ATTACHMENT STRUCTURE WITH FAILED RIVETS AND A CRACK IN THE BULKHEAD 33 WEB. A TEST WAS CONDUCTED WITH ALL FIVE RIVETS WHICH ATTACH THE TOP FLANGE OF THE "U" SHAPED MACHINE PART TO THE UPPER "C" CHANNEL ON ONE SIDE REMOVED. IN ADDITION, THE FIRST THREE RIVETS FORWARD FROM BULKHEAD 33 - THESE ATTACHED THE "C" CHANNEL TO THE SKIN - WERE REMOVED; AND THERE WAS A 3-INCH CRACK CUT IN THE BULKHEAD 33 WEB. THIS DEGRADED STRUCTURE HELD THE MOST CRITICAL LIMIT LOAD WITHOUT ADDITIONAL FAILURE OR EXCESSIVE DEFLECTION. THE TEST, WHICH WAS WITNESSED BY THE CTA, PROVIDE STRONG EVIDENCE THAT LOOSE OR FAIL FASTENERS CONNECTING THE "U" SHAPED MACHINE PART TO THE "C" CHANNEL WOULD NOT CONSTITUTE AN EMINENT SAFETY HAZARD. THEREFORE, THE FAA WAS UNABLE TO FIND A SAFETY NEED TO "GROUND" THE AFFECTED AIRPLANES. A COPY OF AD T85-01-51 AND A COPY OF THE JANUARY 9 TELEGRAM FROM THE CTA IS ENCLOSED.