Skip Ribbon Commands
Skip to main content
Safety Recommendation Details

Safety Recommendation A-86-078
Details
Synopsis: ON AUGUST 2, 1985, AT 1805:52 CENTRAL DAYLIGHT TIME, DELTA AIR LINES (DELTA) FLIGHT 191, A LOCKHEED L-1011-385-1, N726DA, CRASHED WHILE APPROACHING TO LAND ON RUNWAY 17L AT THE DALLAS/FORT WORTH INTERNATIONAL (DFW) AIRPORT, TEXAS. WHILE PASSING THROUGH THE RAIN SHAFT BENEATH A THUNDERSTORM, FLIGHT 191 ENTERED A MICROBURST WHICH THE PILOT WAS UNABLE TO TRAVERSE SUCCESSFULLY. THE AIRPLANE STRUCK THE GROUND ABOUT 6,300 FEET NORTH OF THE APPROACH END OF RUNWAY 17L, HIT A CAR ON A HIGHWAY NORTH OF THE RUNWAY KILLING THE DRIVER, STRUCK TWO WATER TANKS ON THE AIRPORT, AND BROKE APART. EXCEPT FOR A SECTION OF THE AIRPLANE CONTAINING THE AFT FUSELAGE AND EMPENNAGE, THE REMAINDER OF THE AIRPLANE DISINTEGRATED DURING THE IMPACT SEQUENCE, AND A SEVERE FIRE ERUPTED DURING THE IMPACT SEQUENCE. OF THE 163 PERSONS ABOARD, 134 PASSENGERS AND CREWMEMBERS WERE KILLED; 26 PAS SENGERS AND 3 CABIN ATTENDANTS SURVIVED.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION AND THE NATIONAL WEATHER SERVICE: EXPEDITE THE IMPLEMENTATION OF EQUIPMENT TO UPGRADE ALL CENTER WEATHER SERVICE UNITS TO THE STATE OF THE TECHNOLOGY IN DATA ACQUISITION AND DISPLAY CAPABILITY.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: DALLAS/FT WORTH, TX, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA85AA031
Accident Reports: Delta Air Lines, Inc., Lockheed L-1011-385-1, N726DA
Report #: AAR-86-05
Accident Date: 8/2/1985
Issue Date: 9/3/1986
Date Closed: 12/11/1991
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service (Closed - Acceptable Action)
Keyword(s): Air Traffic Control, Weather, Weather Equipment/Products/Reports

Safety Recommendation History
From: NTSB
To: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
Date: 1/19/1990
Response:

From: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
To: NTSB
Date: 7/22/1988
Response: DIFAX EQUIPMENT WILL REPLACE NAFAX EQUIPMENT. FUNDING APPROVED & PROCUREMENT BEGUN IN ACQUIRING ZENTITH PERSONAL COMPUTER FOR THE CWSU'S, ALLOWING DIRECT LINK TO THE PRIMARY NWS COMMUNICATIONS NETWORK. FAA SPECIFICATION FOR THE METEOROLOGICAL WEATHER PROCESSOR HAVE BEEN REVIEWED & AN RFP WILL BE RELEASED SHORTLY.

From: NTSB
To: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
Date: 10/19/1987
Response:

From: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
To: NTSB
Date: 6/4/1987
Response: NO RESPONSE RECEIVED.

From: NTSB
To: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
Date: 6/4/1987
Response:

From: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
To: NTSB
Date: 6/1/1987
Response: THE NWS WHOLEHEARTEDLY WELCOMES FAA EFFORTS AND IS WORKING CLOSELY WITH THE FAA IN EVALUATING AND PLANNING FOR THE ACQUISITION OF IMPROVED METEOROLOGICAL WORKSTATIONS IN THE CWSU'S.

From: NTSB
To: FAA
Date: 12/11/1991
Response: The Safety Board notes that the FAA is in the process of implementing the real-time weather processor and the meteorologist weather processor at each air route traffic control center/area control facility. In addition, the Center Weather Service Units are scheduled to receive the Next Generation Weather Radar displays as they become available. Based on the above information, the Safety Board classifies Safety Recomendation A-86-78 as "Closed--Acceptable Action." However, we request that the FAA continue to keep the Board informed of all progress in the implementation of equipment to upgrade all Center Weather Service Units.

From: FAA
To: NTSB
Date: 7/5/1991
Response: THE FAA IS TESTING THE LEASED MWP AT THE ATLANTA, FORTH WORTH, AND KANSAS CITY CENTER WEATHER SERVICE UNITS, AND THE CENTRAL FLOW CONTROL FACILITY IN WASHINGTON, D.C. AFTER EVALUATION OF SITE ACCEPTANCE TESTING, THE MWP'S ARE SCHEDULED TO BE DELIVERED, BEGINNING IN JULY 1991, TO THE REMAINING SITES. THE RWP WILL BE DEPLOYED AT ALL AIR ROUTE TRAFFIC CONTROL CENTERS/AREA CONTROL FACILITIES, THE FAA ACADEMY, AND THE FAA TECHNICAL CENTER. DELIVERY OF THE RWP SYSTEM IS SCHEDULED TO BEGIN IN FISCAL YEAR 1995. THE CENTER WEATHER SERVICE UNITS WILL RECEIVE NEXT GENERATION WEATHER RADAR DISPLAY BEGINNING IN LATE 1991.

From: NTSB
To: FAA
Date: 5/24/1989
Response: Thank you for your May 3, 1989, response to the National Transportation Safety Board's Safety Recommendation A-86-78, which concerns expediting the implementation of equipment to upgrade all Center Weather Service Units. As the Safety Board has been working with the FAA's National Airspace System Plan, we are aware of what is contained regarding the development and installation of improved weather capabilities. Your letter did help to further understand some components of the Plan. Pending further action, Safety Recommendation A-86-78 is classified as "Open- -Acceptable Action."

From: FAA
To: NTSB
Date: 5/3/1989
Response: THE FAA'S CENTRAL WEATHER PROCESSOR (CWP) PROGRAM IS AN IMPORTANT ELEMENT OF THE OVERALL NATIONAL AIRSPACE SYSTEM MODERNIZATION EFFORT. THE CWP SYSTEM IS REQUIRED TO PROCESS WEATHER INFORMATION FROM VARIOUS SOURCES AND PROVIDE OUTPUTS TO OTHER SYSTEMS. IT IS UNIQUE IN THAT SOME OF THESE INTERFACING SYSTEMS EXIST TODAY AND ARE WELL DEFINED, WHILE OTHERS ARE STILL UNDER DEVELOPMENT. THE MOST CRITICAL OF THE SYSTEMS STILL UNDER DEVELOPMENT ARE THE ADVANCED AUTOMATION SYSTEM (AAS) WITH ITS SECTOR SUITE CONTROLLER POSITION EQUIPMENT AND THE NEXT GENERATION WEATHER RADAR (NEXRAD) SYSTEM. THE FAA'S EFFORT TO IMPLEMENT THE CWP INVOLVES IMPLEMENTING A COMBINATION OF COMMERCIALLY AVAILABLE EQUIPMENT AND SERVICES AND A CONTRACTOR-DEVELOPED SYSTEM. THIS EFFORT INCLUDES THE IMPLEMENTATION OF THE REAL-TIME WEATHER PROCESSOR (RWP) AND THE METEOROLOGIST WEATHER PROCESSOR (MWP) AT EACH AIR ROUTE TRAFFIC CONTROL CENTER/AREA CONTROL FACILITY. (DESCRIPTIONS OF THE RWP AND MWP FUNCTIONS ARE DELETED FROM THIS RESPONSE SUMMARY FOR BREVITY.) THE RWP IS IN FULL SCALE DEVELOPMENT. A PRELIMINARY DESIGN REVIEW WAS CONDUCTED IN NOVEMBER 1988, THE CRITICAL DESIGN REVIEW IS SCHEDULED FOR FOURTH QUARTER 1989, COMPLETION OF FULL-SCALE DEVELOPMENT IS SCHEDULED FOR 2ND QUARTER 1991, ALONG WITH THE START OF PRODUCTION. FIRST INSTALLATION IS SCHEDULED FOR JANUARY 1995. THE MWP WILL BE PROCURED BY A SERIES OF 5 YEAR LEASES WITH DEPLOYMENT SCHEDULED FOR EARLY 1990. THIS WILL ALLOW MAINTENANCE OF EVOLVING MARKET TECHNOLOGY. I WILL KEEP THE BOARD APPRISED.

From: NTSB
To: FAA
Date: 3/29/1989
Response: This is to request an update for Safety Recommendation A-86-78. We asked the FAA to expedite the implementation of equipment to upgrade all Center Weather Service Units to the state-of-the-art technology in data acquisition and display capability. On June 16, 1986, the FAA indicated that we would be kept informed of the FAA's actions on this recommendation. We would appreciate receiving a progress report. This recommendation remains classified as "Open--Acceptable Action."

From: NTSB
To: FAA
Date: 3/12/1987
Response: The Safety Board continues to believe that there are available technologies which could be used to expedite upgrading the CWSU's. Pending further correspondence on the FAA's efforts to implement the upgrading of CWSU equipment, Safety Recommendation A-86-78 has been classified as "Open-Acceptable Action."

From: FAA
To: NTSB
Date: 12/16/1986
Response: THE FAA AGREES WITH THIS RECOMMENDATION; HOWEVER, THIS RECOMMENDATION DEALS WITH LEADING EDGE TECHNOLOGY ITEMS FOR WHICH THERE ARE NO SHORTCUTS OR IMMEDIATELY AVAILABLE ALTERNATIVES. THE PRIMARY CWSU SYSTEMS ARE ALL PROGRAMMED FOR UPGRADES, AS WELL AS THE PROCESSING AND DISSEMINATION CAPABILITY OF THE CWSU, THE GEOSTATIONARY OPERATIONAL ENVIRONMENTAL SATELLITE, THE AUTOMATED WEATHER OBSERVING SYSTEM, THE LOW LEVEL WIND SHEAR SYSTEM, AND THE LIGHTING DETECTION SYSTEM. THE FAA HAS BEEN INVOLVED IN THE PROCUREMENT OF A NEXT GENERATION WEATHER RADAR FOR MORE THAN 5 YEARS. NO OTHER TECHNOLOGICALLY SUITED DOPPLER WEATHER SYSTEM COULD BE IDENTIFIED, TESTED, AND DEPLOYED IN A MORE TIMELY, COST EFFECTIVE MANNER.