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Safety Recommendation Details

Safety Recommendation A-94-187
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: CONDUCT A COMPLETE NATIONAL REVIEW OF ALL RADAR ENVIRONMENTS USING MSAW SYSTEMS. THIS REVIEW SHOULD ADDRESS ALL USER-DEFINED SITE VARIABLES FOR THE MSAW PROGRAMS THAT CONTROL GENERAL TERRAIN WARNINGS, AS WELL AS RUNWAY CAPTURE BOXES, TO ENSURE COMPLIANCE WITH PRESCRIBED PROCEDURES.
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: 4/8/1996
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 4/8/1996
Response: THE BOARD NOTES THAT THE FAA HAS COMPLETED ITS REVIEW OF 128 OPERATIONAL AUTOMATED RADAR TERMINAL SYSTEM (ARTS) IIA SITES & 62 OPERATIONAL ARTS IIIA SITES TO ENSURE THAT ALL USER-DEFINED SITE VARIABLES FOR THE MSAW PROGRAM COMPLY WITH PRESCRIBED PROCEDURES. THE BOARD UNDERSTANDS THAT PROPER ALIGNMENT OF THE MSAW CAPTURE BOXES AT ALL ARTS IIA & ARTS IIIA SITES HAS BEEN VERIFIED AS OF OCTOBER 1995. THEREFORE, THE BOARD CLASSIFIES A-94-187 "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 1/26/1996
Response: THE FAA HAS COMPLETED ITS REVIEW OF 190 AIR TRAFFIC CONTROL FACILITIES (128 OPERATIONAL ARTS IIA SITES & 62 OPERATIONAL ARTS IIIA SITES) TO ENSURE THAT ALL USER-DEFINED SITE VARIABLES FOR THE MSAW PROGRAM ARE IN COMPLIANCE WITH PRESCRIBED PROCEDURES. AS OF OCTOBER 1995, PROPER ALIGNMENT OF THE MSAW CAPTURE BOXES HAS BEEN VERIFIED AT ALL ARTS IIA & ARTS IIIA SITES. I CONSIDER THE FAA'S ACTION TO BE COMPLETED ON THIS RECOMMENDATION.

From: NTSB
To: FAA
Date: 11/20/1995
Response: THE BOARD UNDERSTANDS THAT REVIEWS ARE BEING CONDUCTED AT 190 AIR TRAFFIC CONTROL FACILITIES TO ENSURE THAT ALL USER-DEFINED SITE VARIABLES FOR MSAW PROGRAM COMPLY WITH PRESCRIBED PROCEDURES. THIS VERIFICATION REVIEW IS TAKING LONGER THAN ORIGINALLY ANTICIPATED, & THE FAA COMPLETE VERIFICATION OF THE PROPER ALIGNMENT OF MSAW CAPTURE BOXES AT ALL FACILITIES BY DECEMBER 1995. PENDING COMPLETION & RESPONSE FROM THE FAA THAT THIS REVIEW IS COMPLETED AT ALL FACILITIES, THE BOARD CLASSIFIES A-94-187 "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 9/27/1995
Response: REVIEW ARE BEING CONDUCTED AT 190 AIR TRAFFIC COANTROL FACILITIES (128 OPERATIONAL ARTS IIA SITES & 62 OPERATIONAL ARTS IIIA SITES) TO ENSURE THAT ALL USER-DEFINED SITE VARIABLES FOR THE MSAW PROGRAM ARE IN COMPLIANCE WITH PRESCRIBED PROCEDURES. TO DATE, PROPER ALIGNMENT OF THE MSAW CAPTURE BOXES HAS BEEN VERIFIED AT 56 ARTS IIA SITES & 30 ARTS IIIA SITES. THE VERIFICATION REVIEW IS TAKING LONGER THAN ORIGINALLY ANTICIPATED. THE FAA WILL COMPLETE VERIFICATION OF THE PROPER ALIGNMENT OF MSAW CAPTURE BOXES AT THE REMAINING FACILITIES BY DECEMBER 29/95. I WILL KEEP THE BOARD INFORMED OF THE FAA'S PROGRESS ON THIS SAFETY RECOMMENDATION.

From: NTSB
To: FAA
Date: 5/25/1995
Response: THE BOARD NOTES THAT THE FAA PLANS TO HAVE EACH AIR TRAFFIC FACILITY USING AN MSAW SYSTEM REVIEW THE USER-DEFINED SITE VARIABLES FOR THE GENERAL TERRAIN WARNING & RUNWAY CAPTURE BOXES TO ENSURE COMPLIANCE WITH PRESCRIBED RPOCEDURES. THE REVIEW COMPLETION DATE, JULY 1995, IS CONSIDERED A TIMELY RESPONSE. THEREFORE, THIS RECOMMENDATION IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE, PENDING NOTIFICATION THAT THIS REVIEW HAS BEEN COMPLETED.

From: NTSB
To: FAA
Date: 4/27/1995
Response: THE BOARD NOTES THAT THE FAA IS DEVELOPING A PROGRAM TO CORRECT THE ERRORS IN THE MSAW ARRANGEMENT AT DULLES, & TO REVIEW ALL OTHER MSAW INSTALLATIONS. PENDING THE ISSUANCE OF THE PROGRAM, & CONFIRMATION OF THE PROPER MSAW INSTALLATION AT ALL U.S. AIRPORTS, A-94-186 & A-187 ARE CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 3/20/1995
Response: EACH AIR TRAFFIC CONTROL FACILITY IN THE RADAR ENVIRONMENT USING MSAW SYSTEMS WILL REVIEW THE MSAW SITE VARIABLES TO ENSURE COMPLIANCE WITH PRESCRIBED PROCEDURES. THIS REVIEW WILL ADDRESS ALL USER-DEFINED SITE VARIABLES FOR THE MSAW PROGRAM THAT CONTROL GENERAL TERRAIN WARNINGS & RUNWAY CAPTURE BOXES TO ENSURE COMPLIANCE WITH PRESCRIBED PROCEDURES. THE REVIEW WILL BEGIN IN APRIL & CONCLUDE IN JULY 1995. I WILL KEEP THE BOARD INFORMED OF THE FAA'S PROGRESS ON THIS RECOMMENDATION.

From: FAA
To: NTSB
Date: 1/24/1995
Response: THE FAA AGREES WITH THESE SAFETY RECOMMENDATION NA PROGRAM IS BEING DEVELOP FOR THE REVIEW OF WASHINGTON DULLES INTERNATIONAL AIRPORT & OTHER AIRPORTS WHICH USE MINIMUM SAFE ALTITUDE WARNING SYSTEMS. I WILL PROVIDE THE BOARD WITH THE FAA COURSE OF ACTION TO ADDRESS THESE RECOMMENDATION BY 3/31/95.