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Safety Recommendation Details

Safety Recommendation A-77-064
Details
Synopsis: ON APRIL 4, 1977, SOUTHERN AIRWAYS, INC., FLIGHT 242, A DC-9-31, CRASHED AT NEW HOPE, GEORGIA, AS ITS CREW ATTEMPTED AN EMERGENCY LANDING ON A HIGHWAY; 70 PERSONS DIED AND 24 PERSONS WERE INJURED ASA RESULT. THE NATIONAL TRANSPORTATION SAFETY BOARD'S INVESTIGATION DISCLOSED THAT THE FLIGHT HAD ENTERED A RELATIVELY SMALL PRECIPITATION AREA CLASSIFIED BY THE NATIONAL WEATHER SERVICE (NWS) AS INTENSE, OR LEVEL-5. THIS SMALL INTENSE AREA WAS PART OF A CONSIDERABLY LARGER AREA OF LESSER INTENSITIES. BY THE TIME THE FLIGHT HAD LEFT THIS SMALL INTENSE AREA, THE LEVEL HAD RISEN TO A LEVEL-6, THE HIGHEST LEVEL CURRENTLY USED BY NWS. THE BOARD BELIEVES THAT HAD THIS INTENSE AREA BEEN IDENTIFIED ADEQUATELY AND IN REAL- TIME TO BOTH THE PILOT AND CONTROLLER, THE FLIGHTPATH OF FLIGHT 242 MIGHT HAVE DIFFERED FROM THAT ACTUALLY FLOWN.
Recommendation: ESTABLISH A STANDARD SCALE OF THUNDERSTORM INTENSITY BASED ON THE NWS' SIX-LEVEL SCALE AND PROMOTE ITS WIDESPREAD USE AS A COMMON LANGUAGE TO DESCRIBE THUNDERSTORM PRECIPITATION INTENSITY. ADDITIONALLY, INDOCTRINATE PILOTS AND AIR TRAFFIC CONTROL PERSONNEL IN THE USE OF THIS SYSTEM.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: New Hope, GA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA77AA015
Accident Reports: Southern Airways, Inc., DC-9-31, N1335U
Report #: AAR-78-03
Accident Date: 4/4/1977
Issue Date: 9/20/1977
Date Closed: 5/4/1978
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Weather, Thunderstorms/Rain/Snow, Training and Education, Air Traffic Control

Safety Recommendation History
From: FAA
To: NTSB
Date: 12/8/1977
Response: FAA LTR: ATS HAS TAKEN APPROPRIATE STEPS FOR IMPLEMENTING THE NTSB RECOMMENDATION TO ESTABLISH A STANDARD SCALE OF THUNDERSTORM INTENSITY, BASED UPON THE NWS SIX-LEVEL SCALE. ACTION HAS BEEN TAKEN TO PROMOTE WIDESPREAD USE THROUGHOUT THE AIR TRAFFIC SERVICE OF A COMMON LANGUAGE TO DESCRIBE THUNDERSTORM INTENSITY. THE DOT/FAA NOTICE N7110.510 DATED JUNE 21, 1977, SERVED TO ACQUAINT AIR TRAFFIC CONTROLLER SPECIALISTS WITH DESCRIPTIVE TERM BY THE NWS, AND AUTHORIZES THEIR USE IN THE AIR TRAFFIC SYSTEM. THUNDERSTORM INTENSITY LEVELS WERE PUBLISHED IN THE AIRMAN'S INFORMATION MANUAL, PART 3A, ON SEPTEMBER 1, 1977. THIS PUBLICATION ADVISES PILOTS OF THE NWS STANDARD SIX-LEVEL SCALE AND CITES EXAMPLES OF STANDARD PHRASEOLOGY TO BE USED BY CONTROLLERS DESCRIBING THUNDERSTORM INTENSITY LEVELS. DEFINITIONS AND AN EXPLANATION OF THE GLOSSARY OF THE AIR TRAFFIC CONTROL MANUAL AND THE FLIGHT SERVICE STATION MANUAL EFFECTIVE JANUARY 1, 1978.