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Safety Recommendation Details

Safety Recommendation A-80-140
Details
Synopsis: ON JUNE 12, 1980, AN AIR WISCONSIN, INC., SWEARINGEN SA-226 METRO CRASHED NEAR VALLEY, NEBRASKA, KILLING 13 PERSONS AND SERIOUSLY INJURING 2 OTHERS. THE AIRCRAFT ENCOUNTERED AN AREA OF SEVERE THUNDERSTORMS WHILE AT AN ALTITUDE OF LESS THAN 6,000 FT AND EXPERIENCED A SIMULTANEOUS LOSS OF POWER TO BOTH ENGINES BECAUSE OF MASSIVE WATER INGESTION. DURING ITS INVESTIGATION OF THE ACCIDENT, THE NATIONAL TRANSPORTATION SAFETY BOARD DETERMINED THAT THE NATIONAL WEATHER SERVICE METEOROLOGISTS AT THE MINNEAPOLIS CENTER WEATHER SERVICE UNIT WERE AWARE OF THE THUNDERSTORMS WHICH HAD DEVELOPED IN THE VICINITY OF THE ACCIDENT SITE AND HAD BRIEFED SUPERVISORY AIR TRAFFIC CONTROL PERSONNEL ON THE LOCATION AND SEVERITY OF THE STORM CELLS. IN ADDITION, THE METEOROLOGISTS WERE AWARE OF CONVECTIVE SIGMET'S WHICH FORECAST THE SEVERE THUNDERSTORM ACTIVITY. BOTH METEOROLOGISTS TESTIFIED AT THE PUBLIC HEARING THAT THEY BELIEVED THAT THE CONVECTIVE SIGMET'S WHICH WERE IN EFFECT DESCRIBED ADEQUATELY THE EXISTING METEOROLOGICAL CONDITIONS. THEREFORE, NO CENTER WEATHER ADVISORIES WERE ISSUED TO SUPPLEMENT THE EXISTING CONVECTIVE SIGMET'S.
Recommendation: THE NTSB RECOMMENDS THAT THE NATIONAL WEATHER SERVICE: REQUIRE THAT ALL SEVERE WEATHER WARNINGS AND SIGNIFICANT WEATHER RADAR OBSERVATIONS ISSUED BY A NATIONAL WEATHER SERVICE OFFICE EXPECTED TO AFFECT THE AIRSPACE OF AN AIR TRAFFIC CONTROL APPROACH CONTROL FACILITY BE TRANSMITTED BY THAT OFFICE TO THE FACILITY BY THE MOST EXPEDITIOUS MEANS AVAILABLE.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Alternate Action
Mode: Aviation
Location: Valley, NE, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA80AA019
Accident Reports: Air Wisconsin, Inc., Swearingen A-226 Metro, N650S
Report #: AAR-80-15
Accident Date: 6/12/1980
Issue Date: 1/5/1981
Date Closed: 4/12/1982
Addressee(s) and Addressee Status: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service (Closed--No Longer Applicable)
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: 4/12/1982
Response:

From: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
To: NTSB
Date: 12/3/1981
Response: NATIONAL WEATHER SERVICE LTR: THE NWS HAS BEEN DEEPLY CONCERNED ABOUT THE FREQUENCY OF FATAL THUNDERSTORM-RELATED AIRCRAFT ACCIDENTS AND HAS PUT CONSIDERABLE EFFORT INTO THE IMPLEMENTATION OF THE MOST EFFECTIVE AND EFFICIENT MEANS TO REDUCE SUCH OCCURRENCES. WE RECOGNIZE THAT THE DISSEMINATION OF REAL-TIME WEATHER INTELLIGENCE TO THE PILOT, BOTH ON THE GROUND AND IN THE AIR, DOMINATES THE PROBLEM, AND WE HAVE BEEN WORKING WITH THE FAA TO FIND THE SOLUTIONS. THE RECENT INAUGURATION OF THE CONVECTIVE SIGMET AND CWSU PROGRAMS REPRESENTS THE MOST VISIBLE ACTIONS TO MEET THIS GOAL. UNFORTUNATELY, THE ABILITY OF THE NWS TO ACCOMPLISH ITS MISSION AND TO SATISFY THE REQUIREMENTS AND DEMANDS OF ITS MANY AND VARIED USERS FORCES A SELECTION OF MISSION AND EMPLOYEE WORK PRIORITIES. WHEN CONFLICTS IN PRIORITIES ARISE, OUR PRIMARY OBJECTIVE IS TO GET THE WARNING OUT AS FAST AS POSSIBLE TO THE MAXIMUM NUMBER OF PEOPLE AFFECTED. WITH THIS IN MIND, THE WORDING OF THE SEVERE WEATHER WARNING AND THE MANNER IN WHICH IT IS DISSEMINATED IS DIRECTED TOWARD THE GENERAL PUBLIC AND GROUND BASE OPERATIONS. THIS SHOULD NOT BE INTERPRETED TO MEAN THAT THE NWS HAS ABROGATED ITS RESPONSIBILITY TO THE AVIATION USER. THERE ARE MANY PRODUCTS, PROGRAMS, AND SERVICES EXCLUSIVELY DEDICATED TO AND DESIGNED FOR THE NEEDS OF AVIATION. RATHER THAN UNFAVORABLY IMPACTING THE BASIC SERVICES WE NOW PROVIDE, OUR GOAL IS TO IMPROVE THE EXISTING AVIATION PRODUCTS AND PROGRAMS. WE WILL INSTRUCT OUR AREA MANAGERS TO MEET WITH THE ADMINISTRATIVE PERSONNEL OF THE LOCAL FAA FACILITIES WITHIN THEIR AREA OF RESPONSIBILITY FOR THE PURPOSE OF REVIEWING THE EXCHANGE OF WEATHER INTELLIGENCE BETWEEN OUR AGENCIES. SUBSEQUENT TO THE IDENTIFICATION OF ANY CHANGE TO THE REQUIREMENTS OF THE FAA AND LOCAL NWS OFFICE WORKLOAD CONSIDERATIONS PERMITTING, APPROPRIATE ADJUSTMENTS WILL BE MADE.

From: NTSB
To: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
Date: 7/1/1981
Response:

From: United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service
To: NTSB
Date: 2/27/1981
Response: NATIONAL WEATHER SERVICE LTR: SEVERE WEATHER WARNINGS ARE NOT INTENDED FOR IN-FLIGHT OPERATIONS. THEIR EFFECTIVENESS WOULD BE MINIMAL TO THE HIGHLY MOBILE AVIATION USER. THIS IS BECAUSE NONE OF THEIR NAVIGATIONAL AIDS CONTAIN THE LOCAL REFERENCES USED IN WARNINGS. PILOTS, AND EVEN CONTROLLERS ARE ALSO UNLIKELY TO BE FAMILIAR WITH ALL OF THESE REFERENCES. AS A RESULT, THE RELAY OF WARNINGS AS SUGGESTED BY A-80-140 WOULD NOT ENHANCE THE ACCURACY OR DETAIL OF WEATHER INTELLIGENCE AVAILABLE TO THE AVIATION COMMUNITY.