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Safety Recommendation Details

Safety Recommendation A-76-034
Details
Synopsis: ON JUNE 24, 1975, EASTERN AIR LINES FLIGHT 66, A BOEING 727, CRASHED DURING A PRECISION INSTRUMENT APPROACH TO THE JOHN F. KENNEDY INTERNATIONAL AIRPORT, JAMAICA, NEW YORK. ONE HUNDRED AND THIRTEEN PERSONS DIED FROM THE INJURIES THAT THEY RECEIVED. THE NATIONAL TRANSPORTATION SAFETY BOARD'S INVESTIGATION OF THE ACCIDENT DISCLOSED THAT THE AIRCRAFT DEVELOPED A HIGH DESCENT RATE AS IT PASSED THROUGH OR BELOW THE BASE OF A MATURE THUNDERSTORM. THE STORM WAS ASTRIDE THE APPROACH COURSE AND APPROXIMATELY 1 MILE FROM THE END OF THE RUNWAY. THE PILOTS OF OTHER FLIGHTS WHICH PRECEDED FLIGHT66 ON THE APPROACH REPORTED THAT THEY TOO HAD ENCOUNTERED PROBLEMS IN CONTROLLING THEIR AIRCRAFT TO MAINTAIN A SAFE APPROACH PROFILE. THESE AIRCRAFT AVOIDED AN ACCIDENT POSSIBLY BECAUSE THE PREVAILING CONDITIONS WERE LESS SEVERE OR BECAUSE THE PILOTS RECOGNIZED AND RESPONDED TO THE SITUATION FASTER THAN THE PILOTS OF FLIGHT 66.
Recommendation: REQUIRE INCLUSION OF THE WIND SHEAR PENETRATION CAPABILITY OF AN AIRPLANE AS AN OPERATIONAL LIMITATION IN THE AIRPLANE'S OPERATIONS MANUAL, AND REQUIRE THAT PILOTS APPLY THIS LIMITATION AS A CRITERION FOR THE INITIATION OF A TAKEOFF FROM, OR AN APPROACH TO, AN AIRPORT WHERE EQUIPMENT IS AVAILABLE TO MEASURE THE SEVERITY OF A THUNDERSTORM OR THE MAGNITUDE OF CHANGE IN WIND VELOCITY.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Reconsidered
Mode: Aviation
Location: Jamaica, NY, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA75AZ015
Accident Reports: Eastern Airlines, Inc., Boeing 727-225
Report #: AAR-76-08
Accident Date: 6/24/1975
Issue Date: 3/9/1976
Date Closed: 2/22/1988
Addressee(s) and Addressee Status: FAA (Closed - Reconsidered)
Keyword(s): Low Level Windshear, Weather, Wind

Safety Recommendation History
From: NTSB
To: FAA
Date: 2/22/1988
Response: Based on the knowledge of windshear available in 1976, the board believed that it would be practical to provide pilots with quantita- tive information about their airplane's capability to penetrate windshear so that they could make informed go-no go decisions. However, the know- ledge accrued from the extensive research of the convective windshear phenomena during the past decade has prompted us to reconsider this position. We now know that the winds associated with a downburst are extremely complex, being characterized by the fanning out of the strong down flow and, in some cases, the formation of one or more strong vortex rings surrounding the center of the downshaft. The resultant combinations of horizontal and vertical shears are not describable in terms which can berelated to aircraft performance. The rapidity of changes in the microburst wind velocities makes it infeasible and perhaps unsafe to use reported conditions as a criteria for flying through a visible or otherwise evident convective windshear. The board now believes that all windshears which are associated with convective thunderstorms must be considered as potential flight hazards. As a result of today's enhanced knowledge of the windshearphenomena and other efforts being taken, a-76-34 is closed-reconsidered.

From: FAA
To: NTSB
Date: 5/7/1987
Response: AS STATED IN THE BOARD'S LETTER DATED 8/21/81, THIS RECOM MENDATION WAS CLASSIFIED AS OPEN--ACCEPTABLE ALTERNATE ACTION PENDING RECEIPT OF THE AC DEALING WITH INSTALLATION AND USE OF AIRBORNE EQUIPMENT TO BE USED BY THE AIRCREW. IN MY LETTER DATED 9/24/85, I SENT THE BOARD AC 00-50A, LOW LEVEL WIND SHEAR, ISSUED 1/23/79, AND AC 120-41, CRITERIA FOR OPERATIONAL APPROVAL OF AIRBORNE WIND SHEAR ALERTING AND FLIGHT GUIDANCE SYSTEMS, ISSUED 11/7/83. I CONSIDER THE FAA'S ACTION TO BE COMPLETED, AND I PLAN NO FURTHER ACTION ON THIS RECOMMENDATION.

From: FAA
To: NTSB
Date: 9/16/1986
Response:

From: NTSB
To: FAA
Date: 9/16/1986
Response: In the course of the safety board's investigation of an accidentinvolving delta air lines flight 191 at dallas/fort worth internatinationalairport, tx, on 8/2.85, the board has performed a detailed review of 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 letter of 9/24.85, and 5/5/86, and our analysis of the faa's integrated wind shear program plan. The open safety recommendations reviewed by the safety board are as followsa- 74-13, a-76-34, a-77-63, a-80-118, a-83-15, a-83-18, a-83-19, a-83-20,a83-21, a-83- 22, a-83-23, a-83-23, a-83-24, a-83-25, a-85-26, a-85-27. 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. These recommendations have been classified as open-acceptable action.....

From: NTSB
To: FAA
Date: 10/1/1985
Response: By letter dated may 1, 1981, the faa indicated that it was proceeding with the preparation of advisory circular material dealing with the installation and use of airborne equipment to be used by the aircrew for the purpose addressed in this recommendation and that the safety board would be kept advised. For our information, and public docket re- cord, we would appreciate being apprised of actions taken toward resolving this recommendation. Safety recommendation a-76-34 remains classification an open--acceptable alternate action status.

From: FAA
To: NTSB
Date: 9/24/1985
Response: As noted in our response dated may 1, 1981, the faa advised the board that it is possible to define the acceleration capability or windshear penetration capability of an airplane. It had also been found, however, that the translation of these parameters into operational limitationsinvolved too many variables for useful incorporation into an airplane's operational manual. The faa advised the board that we planned, as an alternative action, to prepare advisory circular (ac) material dealing withinstallation and use of airborne equipment to be used by the aircrew for the purpose addressed in the subject recommendation. As noted in the board's letter dated august 21, 1981, the board concurred with this alter- native action. However, a review of the faa's files disclosed that the board was not in receipt of the ac material that was issued. Therefore, enclosed for the board's information is a copy of ac 00-50a, low level wind shear, issued january 23, 1979, and ac 120-41, criteria for operational approval of airborne wind shear alerting and flight guidance systems, issued november 7, 1983. I consider our action completed on this recommendation.

From: NTSB
To: FAA
Date: 8/21/1981
Response: We concur with the faa regarding the difficulty of translating aircraft acceleration into operational parameters compatible with present wind shear information and believe the efforts made to date are reasonable. We will be pleased to receive the advisory circular when published. This recommendation is classified in an open--acceptable alternate action. Status.

From: FAA
To: NTSB
Date: 5/1/1981
Response: FAA LTR: " . . . IT IS POSSIBLE TO DEFINE THE ACCELERATION CAPABILITY OF WIND SHEAR PENETRATION CAPABILITY OF AN AIRPLANE. IT HAS BEEN FOUND, HOWEVER, THAT TRANSLATIONS OF THESE PARAMETERS INTO OPERATIONAL LIMITATIONS INVOLVES TOO MANY VARIABLES FOR USEFUL INCORPORATION INTO AN AIRPLANE'S OPERATIONAL MANUAL. THE FAA IS, HOWEVER, PROCEEDING WITH THE PREPARATION OF ADVISORY CIRCULAR MATERIAL DEALING WITH INSTALLATION AND USE OF AIRBORNE EQUIPMENT TO BE USED BY THE AIRCREW FOR THE PURPOSE ADDRESSED IN THE SUBJECT RECOMMENDATION. WE WILL FORWARD A COPY OF THIS MATERIAL TO THE BOARD WHEN PUBLISHED."

From: NTSB
To: FAA
Date: 4/17/1981
Response: We were advised on july 28, 1980, to expect an answer in the near future. We are anxious to evaluate the progress of these recommenda- tions and would very much appreciate an updated status report.

From: FAA
To: NTSB
Date: 7/28/1980
Response: FAA LTR: WE ARE REVIEWING THE STATUS OF ACTIONS TAKEN AND WILL ADVISE THE BOARD IN THE NEAR FUTURE.

From: NTSB
To: FAA
Date: 7/21/1980
Response: At the last ntsb/faa quarterly meeting held on march 12, 1980, the faa staff were advised that anumber of these recommendations were in an open status awaiting a further response from the faa. In order evaluate the progress of the recommendations and update the public docket, we would appreciate an updated status report.

From: FAA
To: NTSB
Date: 7/7/1976
Response: FAA LETTER: AS STATED IN OUR RESPONSE TO A-76-31, WE ARE CURRENTLY PURSUING THE RESEARCH NECESSARY TO ESTABLISH WIND SHEAR RELATED OPERATIONAL LIMITATIONS FOR GENERAL AIRCRAFT TYPES. REGULATORY STEPS MUST AWAIT THE SUCCESSFUL COMPLETION OF THE RESEARCH AND THE INSTALLATION OF APPROPRIATE MEASUREMENT EQUIPMENT.