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Safety Recommendation Details

Safety Recommendation A-94-188
Details
Synopsis: THE NATIONAL TRANSPORTATION SAFETY BOARD'S INVESTIGATION OF A RECENT ACCIDENT INVOLVING A LANDING APPROACH, IN INSTRUMENT METEOROLOGICAL CONDITIONS, AT WASHINGTON DULLES INTERNATIONAL AIRPORT (IAD), HAS REVEALED SOFTWARE DISCREPANCIES WITH THE MINIMUM SAFE ALTITUDE WARNING SYSTEM (MSAW) AND LOW LEVEL WINDSHEAR ALERT SYSTEM (LLWAS) OPERATING AT IAD AT THE TIME OF THE ACCIDENT. THE DISCREPANCIES ARE BELIEVED TO AFFECT THE ACCURACY OF THE WARNING SYSTEMS. THE SAETY BOARD BELIEVES THAT ACTION IS REQUIRED TO CORRECT THE DISCREPANCIES AT IAD, AND MAY BE REQUIRED TO CORRECT SIMILAR DISCREPANCIES AT OTHER AIRPORTS THROUGHOUT THE COUNTRY.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: ENSURE THAT ALL AIRPORTS EQUIPPED WITH THE PHASE II (ENHANCED) LLWAS ARE USING GEOMETRIC CONFIGURATION FILES APPROPRIATE TO THOSE FACILITIES.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: CHANTILLY, VA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA94MA061
Accident Reports: Controlled Collision with Terrain Transportes Aereos Ejecutivos, S.A. (TAESA) Learjet 25D, XA-BBA
Report #: AAR-95-02
Accident Date: 6/18/1994
Issue Date: 11/21/1994
Date Closed: 8/29/1995
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 8/29/1995
Response: THE BOARD NOTES THAT WHEN THE FAA RELEASES NEW SOFTWARE TO THE FIELD, A CHECKLIST IS ATTACHED TO ENSURE THAT THE SOFTWARE HAS BEEN LOADED CORRECTLY & THAT GEOMETRIC CONFIGURATION FILES FOR THE AIRPORT HAVE BEEN REINSTALLED. THESE PROCEDURES, AS PROMULGATED IN FAA REVISED ORDER 6560.13B, "MAINTENANCE OF AVIATION METEOROLOGICAL SYSTEMS & MISCELLANEOUS AIDS." APPEAR TO APPROPRIATELY ENSURE THAT OPTIMUM MICROBUST DETECTION CAPABILITY WILL BE ACHIEVED AT ALL PHASE II LLWAS AIRPORTS. THEREFORE, THE BOARD CLASSIFIES A-94-188 "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 6/1/1995
Response: AS STATED IN THE FAA LETTER DATED 1/24/95, WHEN NEW SOFTWARE IS RELEASED TO THE FIELD, THE FAA ATTACHES A CHECKLIST TO ENSURE THAT THE SOFTWARE HAS BEEN LOADED CORRECTLY & THAT THE GEOMETRIC CONFIGURATION FILES FOR THE AIRPORT HAVE BEEN REINSTALLED. THESE CURRENT PROCEDURES PROPERLY ADDRESS THE INSTALLATION & LOADING OF NEW SOFTWARE IN THE THE FIELD.

From: NTSB
To: FAA
Date: 4/27/1995
Response: THE BOARD NOTES THAT THE FAA IS ISSUING A REVISION TO ORDER 6560.13B, MAINTENANCE OF AVIATION METEOROLOGICAL SYSTEMS & MISCELLANEOUS AIDS, TO INCLUDE A PERFORMANCE CHECK WHICH WILL VERIFY THAT THE CORRECT GEOMETRIC CONFIGURATION FILES ARE INSTALLED IN LLWAS SYSTEMS. ISSUANCE OF A NOTICE TO ALL FIELD PERSONNEL TO INSTALL THE CORRECT GCF AFTER THE COMPUTER HAS BEEN REPAIRED IS APPROPRIATE. UNTIL THE REVISION TO ORDER 6560.13B IS RECEIVED, A-94-188 CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 1/24/1995
Response: THE FAA AGREES WITH THE INTENT OF THIS RECOMMENDATION. WHEN NEW SOFTWARE IS RELEASED TO THE FIELD, THE FAA ATTACHES A CHECKLIST TO ENSURE THAT THE SOFTWARE HAS BEEN LOADED CORRECTLY & THAT THE GEOMETRIC CONFIGURATION IS REPLACED, PROCEDURES ARE CONTAINED IN THE INSTRUCTION BOOK APPROPRIATED AIRPORT. THE FAA WILL REVISE ORDER 6560.13B, MAINTENANCE OF AVIATION METEOROLOGICAL SYSTEMS & MISCELLANEOUS AIDS, TO INCLUDE A PERFORMANCE CHECK TO VERIFY THE CORRECT GEOMETRIC CONFIGURATION FILE ARE INSTALLED. IN THE INTERIM, THE FAA WILL ISSUE A NOTICE TO ALL FIELD PERSONNEL TO REMIND THEM TO INSTALL THE CORRECT GEOMETRIC CONFIGURATION FILES AFTER THE COMPUTER HAS BEEN REPAIRED. I WILL PROVIDE THE BOARD WITH A COPY OF THE REVISION TO ORDER 6560.13B AS SOON AS IT IS REVISED.