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Safety Recommendation Details

Safety Recommendation A-83-023
Details
Synopsis: ON JULY 9, 1982, PAN AMERICAN WORLD AIRWAYS FLIGHT 759 CRASHED AFTER TAKING OFF FROM RUNWAY 10 AT NEW ORLEANS INTERNATIONAL AIRPORT, KENNER, LOUISIANA. WHEN FLIGHT 759 TOOK OFF, THERE WERE ISOLATED HEAVY SHOWERS OVER THE AIRPORT AND TO THE EAST OF THE AIRPORT ALONG THE AIRPLANE'S INTENDED DEPARTURE PATH. LOW LEVEL WIND SHEAR CONDITIONS HAD BEEN DETECTED BY THE AIRPORT'S LOW LEVEL WIND SHEAR ALERT SYSTEM (LLWSAS), AND THE SYSTEM HAD ALARMED SEVERAL TIMES, THE LAST TIME ABOUT 4 MINUTES BEFORE FLIGHT 759'S TAKEOFF. THE SYSTEM WAS NOT ALARMING AT THE TIME THE TAKEOFF CLEARANCE WAS ISSUED; HOWEVER, A WIND SHEAR ADVISORY WAS BROADCAST 2 SECONDS AFTER THE ACCIDENT.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: EXPEDITE THE DEVELOPMENT, TESTING, AND INSTALLATION OF ADVANCED DOPPLER WEATHER RADAR TO DETECT HAZARDOUS WIND SHEARS IN AIRPORT TERMINAL AREAS AND EXPEDITE THE INSTALLATION OF MORE IMMEDIATELY AVAILABLE EQUIPMENT SUCH AS ADD-ON DOPPLER TO PROVIDE FOR DETECTION AND QUANTIFICATION OF WIND SHEAR IN HIGH RISK AIRPORT TERMINAL AREAS.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: Kenner, LA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA82AA028
Accident Reports: Pan American World Airways, Inc., Clipper 759, Boeing 727-235, N4737
Report #: AAR-83-02
Accident Date: 7/9/1982
Issue Date: 3/25/1983
Date Closed: 6/20/1995
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Low Level Windshear, Weather, Wind

Safety Recommendation History
From: NTSB
To: FAA
Date: 6/20/1995
Response: THE INTENT OF A-83-23 IS MET BY THE ACTIONS TAKEN BY THE FAA TO SATISFY A-90-83 & A-90-84. THEREFORE, A-83-23 IS CLASSIFIED "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 2/21/1995
Response: A-83-23 WAS ISSUED IN MARCH 1983. SINCE THAT TIME, THIS RECOMMENDATION HAS BEEN SUPERSEDED BY A-90-83 & 84. THE PROGRAMS THAT THE FAA HAS UNDERWAY IN RESPONSE TO A-90-83 & -84 COMPLETELY ADDRESS A-83-23. CONSEQUENTLY, I REQUEST THAT THE BOARD CLASSIFY THIS RECOMMENDATION AS CLOSED SUPERSEDED BY A-90-83 & -84.

From: NTSB
To: FAA
Date: 6/18/1990
Response: (PER GREEN SHEET A-90-83 THRU -85) The TDWR testbed demonstration programs have provided a high level of confidence that the technical obstacles to a terminal Doppler radar are solvable, yet the operational development of the TDWR may not be completed for 5 years. Further, the Safety Board believes that the FAA should pursue development of an ASR-9 modular enhancement that will provide a Doppler wind measurement capability to that system. This enhancement is especially important since the Terminal NEXRAD Program has been cancelled. The enhanced ASR-9 might be made available for interim use in locations scheduled for late installation of the TDWR and for permanent use at locations not scheduled for TDWR. (Recommendation A- 83-23, issued March 25, 1983, is classified as "Open--Acceptable Action.")

From: FAA
To: NTSB
Date: 2/15/1989
Response: The FAA is procuring 17 terminal Next Generation Weather Radar (NEXRAD) programs to be installed near major airports. The NEXRAD programs will provide windshear detection capability for an interim period until the Terminal Doppler Weather Radar (TDWR) system is available. The NEXRAD production contract was awarded in December 1987 to UNISYS. The first terminal NEXRAD is scheduled to be delivered in mid-1990, and the last unit in mid-1992. The TDWR contract for 47 systems was awarded to Raytheon in November 1988. The contract contains options for additional units if required. The first operational system is scheduled to be delivered in late 1992, and the last system in mid-1994. When the TDWR system becomes available, the terminal NEXRAD units will be reconfigured as standard NEXRAD's and redeployed to offshore NEXRAD locations. The Safety Board is aware of the technology involved in the area and the contents of the contract awarded to UNISYS. Based on the FAA's actions to date, I urge the Safety Board to classify this safety recommendation as "closed."

From: NTSB
To: FAA
Date: 9/16/1986
Response: In the course of the Safety Board's investigation of an accident involving Delta Air Lines flight 191 at Dallas/Fort Worth International Airport, Texas, on August 2, 1985, the Safety Board has performed a detailed review of all Safety Recommendations, currently classified as open, issued to the FAA on the subject of windshear. Also addressed in this review were three Safety Recommendations that discussed the timely detection of severe weather, though not specifically related to windshear or microbursts. The Safety Board's review included past FAA responses, evaluation of the FAA's letters of September 24, 1985, and May 5, 1986, and our analysis of the FAA's Integrated Wind Shear Program Plan. A more descriptive review of the FAA's responses to these Safety Recommendations and of the program plan is contained in appendix H of the Safety Board's report of the Delta flight 191 accident. The open Safety Recommendations reviewed by the Safety Board are as follows: A-74-13 A-76-34 A-77-63 A-80-118 A-83-15 A-83-18 A-83-19 A-83-20 A-83-21 A-83-22 A-83-23 A-83-24 A-83-25 A-83-26 A-83-27 The Safety Board has carefully reviewed the Integrated Wind Shear Program Plan and the two letters from the FAA mentioned above and finds that the actions concurrently being taken and planned by the FAA will comply with the intent of all of the above Safety Recommendations when implemented. Therefore, all of the above-listed Safety Recommendations have been classified as "Open--Acceptable Action" pending completion of the FAA's planned actions. The Safety Board appreciates the FAA's actions to improve windshear detection and avoidance, and in the dissemination of information on windshear.

From: NTSB
To: FAA
Date: 8/21/1986
Response: The Safety Board is pleased to learn that the FAA is reconfiguring some of the Next Generation Weather Radar (NEXRAD) units for temporary use in the terminal environment as a means of achieving more timely windshear detection capability at major airports. The Safety Board appreciates the FAA's effort to expedite the installation of terminal Doppler radar through the use of NEXRAD equipment. The Safety Board trusts that the FAA will continue to expedite efforts to improve the windshear detection capabilities in high risk areas and wishes to be kept informed of further developments. Safety Recommendation A-83-23 has been classified as "Open--Acceptable Action" pending completion of the FAA's efforts.

From: FAA
To: NTSB
Date: 7/10/1986
Response: THE FAA HAS DETERMINED THAT A RADAR SIMILAR TO NEXRAD, BUT OPERATED IN A WIND SHEAR DETECTION MODE, IS REQUIRED TO DETECT HAZARDOUS WIND SHEAR IN THE TERMINAL AREA. THE NEXRAD PROGRAM IS CURRENTLY IN THE VALIDATION PHASE. PRODUCTION CONTRACT IS SCHEDULED FOR JANUARY 1987 WITH INITIAL NEXRAD DELIVERY SCHEDULED FOR JANUARY 1989. THE FAA PLANS TO INSTALL NEXRAD SYSTEMS AT 14 MAJOR AIRPORTS AND OPERATE THESE SYSTEMS AS TERMINAL RADARS FOR AN INTERIM PERIOD. THE FAA PLANS TO PROCURE A NUMBER OF TERMINAL DOPPLER WEATHER RADARS FOR INSTALLATION AT MAJOR AIRPORTS BEGINNING IN 1991.

From: NTSB
To: FAA
Date: 5/29/1984
Response: The Safety Board believes that terminal Doppler weather radar currently represents the best means for detecting and warning of hazardous wind shears in the airport terminal area. We are pleased that the FAA is expediting the development and production of a next generation advanced Doppler weather radar system. We note that the current schedule projects the first system to be installed in late 1987 and all systems to be in place by 1992. Safety Recommendation A-83-23 also recommended that the FAA consider the use of more immediately available technology such as add-on Doppler to provide an interim means for detection and warning of hazardous wind shear. The FAA's response notes that the appropriate software to utilize this add-on Doppler has not been developed. However, on September 21, 1983, one of the Safety Board's meteorologists observed at the Montgomery, Alabama, office of the National Weather Service the use of a Doppler Weather Radar System consisting of a National Weather Service radar and an add-on Data Source: NTSB Recommendations to FAA and FAA Responses Enterprise Doppler Package to locate areas of hazardous weather. The Doppler Weather Radar System at Montgomery has been used with success operationally to provide information on radial velocities, wind shear, and areas of potential turbulence. Public and aviation weather warnings have been issued by the National Weather Service Office based on the data from the Doppler System. Although presently substantial interpretation is needed to identify areas of significant winds and wind shear, personnel at Montgomery are working on software to simplify the data presentation. They have made significant progress in these areas. We understand that the FAA has observed the Doppler Weather Radar System in operation at Montgomery. We urge the FAA to continue to explore the feasibility of using currently available Doppler Weather Radar Systems such as the one in Montgomery and to consider these systems for interim use prior to the deployment of the next generation advanced Doppler Weather Radar System. Safety Recommendation A-83-23 will be classified as "Open--Acceptable Action" pending FAA's further response concerning use of currently available equipment.

From: FAA
To: NTSB
Date: 7/21/1983
Response: FAA LETTER: THE FAA IS PURSUING THE DEVELOPMENT AND DEPLOYMENT OF AIRPORT TERMINAL DOPPLER WEATHER RADAR IN THE MOST EXPEDITIOUS MANNER POSSIBLE. WE BELIEVE THE MOST EFFICIENT MEANS OF ALERTING THE CONTROLLER TO THE PRESENCE OF HAZARDOUS WEATHER IN THE VICINITY OF THE AIRPORT IS TO PROVIDE INTENSITY CONTOURS OF PRECIPITATION AND TURBULENCE DERIVED FROM THE DOPPLER WEATHER RADAR DIRECTLY ON HIS AIRPORT SURVEILLANCE RADAR DISPLAY. ADDITIONALLY, EVERY EFFORT IS BEING MADE TO EXPEDITE THE PROCUREMENT FOR DEVELOPMENT AND PRODUCTION OF THE TERMINAL DOPPLER WEATHER RADAR BY SPECIFYING A NEXT GENERATION DERIVATIVE RADAR. THE CURRENT SCHEDULE CALLS FOR FIRST SYSTEM INSTALLATION IN LATE 1987 AND ALL SYSTEMS INSTALLED BY 1992.