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Safety Recommendation Details

Safety Recommendation A-80-136
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 FOUND NUMEROUS DEFICIENCIES IN THE IMPLEMENTATION OF AIR TRAFFIC CONTROL PROCEDURES WHICH AFFECTED THE ACQUISITION OF WEATHER DATA AND THE DISSEMINATION OF THAT INFORMATION TO SECTOR AIR TRAFFIC CONTROLLERS AND PILOTS. THE SAFETY BOARD ALSO DISCOVERED THAT THE CAPABILITIES OF AIRBORNE WEATHER RADAR ON THE AIRCRAFT TO DETECT SEVERE WEATHER ECHOES WERE LIMITED SIGNIFICANTLY BY RAIN-INDUCED TWO-WAY ATTENUATION, BUT THAT THE PILOTS WERE PROBABLY NOT AWARE OF THE REDUCED CAPABILITY OF THE RADAR.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: REQUIRE THAT THE EFFECT OF PRECIPITATION-INDUCED ATTENUATION ON X-BAND AIRBORNE WEATHER RADAR BE INCORPORATED INTO AIRLINE TRAINING PROGRAMS AND THAT AIRBORNE WEATHER RADAR MANUFACTURERS INCLUDE ATTENUATION DATA IN RADAR OPERATORS HANDBOOKS.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable 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: 6/8/1982
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Flightcrew, RADAR, Training and Education, Weather, Weather Equipment/Products/Reports

Safety Recommendation History
From: NTSB
To: FAA
Date: 6/8/1982
Response:

From: NTSB
To: FAA
Date: 5/24/1982
Response: We are satisfied with the faa's response to these recommendations and classify them in a closed-acceptable action status.

From: FAA
To: NTSB
Date: 4/13/1982
Response: FAA LTR: ON APRIL 10, 1981, WE ISSUED CHANGE 21 TO FAA ORDER 8430.17, AIR CARRIER OPERATIONS BULLETIN, WHICH TRANSMITS A REVISION TO CHAPTER 8, WEATHER OPERATIONS AND INSTRUMENT SYSTEMS, PARAGRAPH 842, ACOB NO. 7-79-3 AIRBORNE WEATHER RADAR. THE REVISION FURTHER STRESSES THE IMPORTANCE OF OPERATOR KNOWLEDGE OF THE EFFECT PRECIPITATION-INDUCED ATTENUATION ON X-BAND AIRBORNE WEATHER RADAR.

From: FAA
To: NTSB
Date: 4/7/1981
Response: FAA LTR: THE FAA CONCURS IN THIS RECOMMENDATION. WE ARE IN THE PROCESS OF REVISING AIR CARRIER OPERATIONS BULLETIN NO. 7-79-3, AIRBORNE WEATHER RADAR. IN THIS REVISION WE HAVE FURTHER STRESSED THE IMPORTANCE OF OPERATOR KNOWLEDGE OF THE EFFECT OF PRECIPITATION-INDUCED ATTENUATION ON X-BAND AIRBORNE WEATHER RADAR.