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Safety Recommendation Details

Safety Recommendation A-92-058
Details
Synopsis: ON MARCH 3, 1991, A BOEING 737-200 AIRPLANE, OPERATED UNDER 14 CODE OF FEDERAL REGULATIONS (CFR) PART 121 AS UNITED AIRLINES FLIGHT 585, CRASHED DURING ITS APPROACH TO THE COLORADO SPRINGS MUNICIPAL AIRPORT, COLORADO SPRINGS, COLORADO. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AT THE TIME AND THE FLIGHT WAS ON AN INSTRUMENT FLIGHT RULES (IFR) FLIGHT PLAN FROM DENVER, COLORADO. AT ABOUT 0944 MOUNTAIN STANDARD TIME (MST), NUMEROUS WITNESSES REPORTED THAT SHORTLY AFTER ROLLOUT ONTO THE FINAL APPROACH COURSE TO RUNWAY 35, THE AIRPLANE ROLLED STEADILY TO THE RIGHT AND PITCHED NOSE DOWN. THE AIRPLANE CONTINUED TO ROLL TO THE RIGHT AND PITCH DOWN UNITL IT WAS ALMOST IN A VERTICAL ATTITUDE BEFORE COLLIDING WITH THE GROUND. THE AIRPLANE WAS DESTROYED, AND THE 2 FLIGHT CREWMEMBERS, 3 FLIGHT ATTENDANTS, AND 20 PASSENGERS ABOARD WERE FATALLY INJURED.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: DEVELOP A BROADER METEOROLOGICAL AIRCRAFT HAZARD PROGRAM TO INCLUDE OTHER AIRPORTS IN OR NEAR MOUNTAINOUS TERRAIN, BASED ON THE RESULTS OBTAINED IN THE COLORADO SPRINGS, COLORADO, AREA.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: COLORADO SPGS, CO, United States
Is Reiterated: Yes
Is Hazmat: No
Is NPRM: No
Accident #: DCA91MA023
Accident Reports: Uncontrolled Descent and Collision with Terrain, United Airlines Flight 585, Boeing 737-200, N999UA, 4 Miles South of Colorado Springs Municipal Airport
Report #: AAR-92-06
Accident Date: 3/3/1991
Issue Date: 7/20/1992
Date Closed: 4/24/2001
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Weather

Safety Recommendation History
From: NTSB
To: FAA
Date: 4/24/2001
Response: IN ADDITION TO THE INFORMATION SUPPLIED BY THE FAA IN ITS 11/6/00, LETTER, THE SAFETY BOARD NOTES THAT THE FAA HAS OTHER PROGRAMS IN PROGRESS TO STUDY TERRAIN-INDUCED TURBULENCE THAT MAY POSE A HAZARD TO AVIATION, INCLUDING A CURRENT PROGRAM IN JUNEAU, ALASKA. THE BOARD IS PLEASED THAT THE FAA CONDUCTED THE EXTENSIVE RESEARCH PROGRAM; ISSUED AC 00-57; AND, AS EVIDENCED BY THE PROGRAM IN JUNEAU, ALASKA, CONTINUES TO INVESTIGATE THIS METEOROLOGICAL PHENOMENA. THEREFORE, BECAUSE OF THE FAA'S EXTENSIVE WORK ON THIS SUBJECT, A-92-58 IS CLASSIFIED "CLOSED--ACCEPTABLE ACTION."

From: NTSB
To: FAA
Date: 3/27/2001
Response: From the accident report concerning the uncontrolled descent of a Boeing 737-200 four miles south of Colorado Springs Municipal Airport (adopted 3/27/2001): In addition, as a result of information developed during the course of this investigation, in its December 8, 1992, report on this accident the Safety Board reiterated the following two safety recommendations that it issued on July 20, 1992 to the Federal Aviation Administration: A-92-57 Develop and implement a meteorological program to observe, document, and analyze potential meteorological aircraft hazards in the area of Colorado Springs, Colorado, with a focus on the approach and departure paths of the Colorado Springs Municipal Airport. This program should be made operational by the winter of 1992. A-92-58 Develop a broader meteorological aircraft hazard program to include other airports in or near mountainous terrain, based on the results obtained in the Colorado Springs, Colorado, area. The FAA's response to these recommendations, dated October 8, 1992, stated that it agreed with the intent of these safety recommendations. The FAA anticipated, based on budget constraints and program priorities, that the work on these projects could start in fiscal year 1995. In its December 8, 1992, report on this accident, the Safety Board noted that the FAA agreed with the intent of these safety recommendations and that it planned to address their intent through an interagency program with the National Oceanic and Atmospheric Administration/Forecast Systems Laboratory or the National Science Foundation/National Center for Atmospheric Research. However, in that report the Safety Board expressed its concern that the FAA believed that due to budget constraints and program priorities, these projects could not be started until fiscal year 1995. The Safety Board stated it understood the difficulty in funding these projects in fiscal year 1993, but believed that the FAA should reevaluate its priorities to include them in 1993. Pending further information concerning fiscal year 1993 funding, the Safety Board classified Safety Recommendations A-92-57 and A-92-58 as “Open—Unacceptable Response.” In a letter dated April 3, 1998, the FAA stated that it had completed several actions to improve the safety of flying in mountainous areas by providing pilots, dispatchers, and others in aviation operations with a series of products that will detect, display, and forecast hazardous mountain winds. Specifically, the FAA noted that, in conjunction with NOAA and NCAR, it had published Advisory Circular 00-57, “Hazardous Mountain Winds and Their Visual Indicators,” to assist pilots in diagnosing the potential for severe wind events in the vicinity of mountainous areas and to provide information on preflight planning techniques and inflight evaluation strategies for avoiding destructive turbulence and loss of aircraft control. In addition, the FAA noted that NOAA and NCAR personnel had collected data on the intensity and direction of wind flows at the Colorado Springs Airport during the period January through March 1997, when mountain-induced activity was known to be prevalent. The FAA stated that the original scope of the experiment at Colorado Springs that had been anticipated in response to Safety Recommendations A-92-57 and –58 had been reduced because of funding constraints and the overall assessments of the priority of safety-related research and, as a result, the project had been terminated. In a letter dated January 20, 1999, the Safety Board stated that it recognized the large amount of meteorological data collected during the Colorado Springs meteorological program in 1997 and urged the FAA to make every effort to ensure the complete and detailed analysis of these data and the timely publication of the results. On the basis of the results, and pending the issuance of a final report by NOAA and NCAR, Safety Recommendation A-92-57 was classified “Open—Acceptable Response.” Regarding Safety Recommendation A-92-58, the Safety Board stated its belief that the FAA should develop a broader meteorological aircraft hazard program to include other airports in or near mountainous areas. Pending the receipt of further information from the FAA about such a program, Safety Recommendation A-92-58 was classified “Open— Unacceptable Response.” On March 2, 2000, the Safety Board requested that the FAA provide a progress report on the actions taken in response to Safety Recommendations A-92-57 and –58.

From: FAA
To: NTSB
Date: 11/6/2000
Response: Letter Mail Controlled 11/13/2000 10:49:46 AM MC# 2001660 THIS SAFETY RECOMMENDATION WAS ADOPTED AT A TIME WHEN THE MOUNTAIN WAVE PHENOMENON WAS CONSIDERED A LIKELY CAUSE OR FACTOR IN THIS ACCIDENT. THE FAA AND NCAR INSTITUTED AN EXTENSIVE PROGRAM TO ADDRESS THE MOUNTAIN WAVE SUBJECT TO INCLUDE REPORTS AND INFORMATION TO PILOTS AND AN ADVISORY CIRCULAR (AC) CONCERNING MOUNTAIN WINDS AND THE ASSOCIATED HAZARDS. RECENTLY, THE BOARD, AS PART OF THE FINAL ACCIDENT REPORT OF USAIR FLIGHT 427, DETERMINED THAT THE CAUSE OF THE UNITED AIRLINES FLIGHT 585 ACCIDENT AT COLORADO SPRINGS, CO, WAS RELATED TO THE MALFUNCTION OF THE RUDDER ON THE BOEING 737. GIVEN THIS DETERMINATION, I REQUEST THAT THE BOARD CLASSIFY A-92-58 IN A "CLOSED ACCEPTABLE" STATUS BASED ON THE EXTENSIVE WORK DONE BY THE FAA AND NCAR TO IDENTIFY THE HAZARDS OF MOUNTAIN WINDS AND TO MAKE THE INFORMATION AVAILABLE TO THE AVIATION INDUSTRY. I AM SUMMARIZING THE WORK OF THE FAA AND NCAR ON THIS SUBJECT TO UNDERSCORE THE EFFORT THAT HAS BEEN COMPLETED TO ADDRESS A-92-58: THE FAA, NOAA, AND NCAR PUBLISHED AC 00-57, "HAZARDOUS MOUNTAIN WINDS AND THEIR VISUAL INDICATORS," TO PROVIDE INFORMATION ON HAZARDOUS MOUNTAIN WINDS AND THEIR EFFECTS ON FLIGHT OPERATIONS NEAR MOUNTAINOUS REGIONS. THE PRIMARY PURPOSE OF AC 00-57 IS TO ASSIST PILOTS INVOLVED IN AVIATION OPERATIONS TO DIAGNOSE THE POTENTIAL FOR SEVERE WIND EVENTS IN THE VICINITY OF MOUNTAINOUS AREAS AND TO PROVIDE INFORMATION ON PREFLIGHT PLANNING TECHNIQUES AND INFLIGHT EVALUATION STRATEGIES FOR AVOIDING DESTRUCTIVE TURBULENCE AND LOSS OF AIRCRAFT CONTROL; NOAA AND NCAR PERSONNEL COLLECTED DATA ON THE INTENSITY AND DIRECTION OF WIND FLOWS AT THE COLORADO SPRINGS AIRPORT DURING THE PERIOD JANUARY THROUGH MARCH 1997, WHEN MOUNTAIN-INDUCED ACTIVITY WAS KNOWN TO BE PREVALENT. A DATA SET WAS DEVELOPED THROUGH THE USE OF ONE LIDAR UNIT, THREE WIND PROFILERS WITH RADIO ACOUSTIC SOUNDING SYSTEM, ANEMOMETERS, AN INSTRUMENTED KING AIR AIRCRAFT THAT TRAVERSED THE LANDING AND TAKEOFF FLIGHT PATH, SIX SURFACE METEOROLOGICAL STATIONS, AN INFRASONIC LABORATORY, AND PILOT REPORTS. NOAA AND NCAR PUBLISHED A REPORT ON THEIR FINDINGS AND; NOAA AND NCAR COMPLETED A REPORT ON LIMITED ANALYSIS OF THE COLORADO SPRINGS DATA. ONE OBJECTIVE OF THE ANALYSIS WAS TO ASSESS THE TURBULENCE DETECTION CAPABILITIES OF THE LIDAR AND GROUND ANEMOMETERS. A FURTHER OBJECTIVE WAS TO DETERMINE THE STRENGTHS OF LIDAR-DETECTED WIND TURBULENCE AS A FUNCTION OF OTHER FACTORS THAT WERE RECORDED DURING THE EXPERIMENT. I BELIEVE THAT THE FAA HAS MET THE FULL INTENT OF THIS SAFETY RECOMMENDATION, AND I CONSIDER THE FAA'S ACTION TO BE COMPLETED.

From: NTSB
To: FAA
Date: 3/16/2000
Response: ON 3/16/00 THE SAFETY BOARD REQUESTED AN UPDATE ON THE STATUS OF THIS RECOMMENDATION.

From: NTSB
To: FAA
Date: 1/20/1999
Response: BASED ON THE INTERIM RESULTS FROM THE COLORADO SPRINGS METEOROLOGICAL PROGRAM, WHICH DOCUMENTED THE EXISTENCE OF MOUNTAIN INDUCED METEOROLOGICAL AIRCRAFT HAZARDS IN THE COLORADO SPRINGS AREA, THE SAFETY BOARD STILL BELIEVES THAT THE FAA SHOULD DEVELOP A BROADER METEOROLOGICAL AIRCRAFT HAZARD PROGRAM TO INCLUDE OTHER AIRPORTS IN OR NEAR MOUNTAINOUS AREAS. THEREFORE, PENDING THE RECEIPT OF FURTHER INFORMATION FROM THE FAA ABOUT A METEOROLOGICAL PROGRAM TO OBSERVE, DOCUMENT, ANALYZE AND REPORT METEOROLOGICAL HAZARDS AT OTHER AIRPORTS IN MOUNTAINOUS AREAS, A-92-58 IS CLASSIFIED "OPEN--UNACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 4/3/1998
Response: Letter Mail Controlled 4/9/98 1:18:54 PM MC# 980453 THE FAA HAS COMPLETED SEVERAL ACTIONS TO IMPROVE THE SAFETY OF FLYING IN MOUNTAINOUS AREAS BY PROVIDING PILOTS, DISPATCHERS, AND OTHERS IN AVIATION OPERATIONS WITH A SERIES OF PRODUCTS THAT WILL DETECT, DISPLAY, AND FORECAST HAZARDOUS MOUNTAIN WINDS. TO DATE, THE FAA HAS ACCOMPLISHED THE FOLLOWING: 1. THE FAA, THE NATIONAL OCEANIC AND ATMOSPHERIC (NOAA), AND THE NATIONAL CENTER FOR ATMOSPHERIC RESEARCH (NCAR) PUBLISHED ADVISORY CIRCULAR (AC) 00-57, "HAZARDOUS MOUNTAIN WINDS AND THEIR VISUAL INDICATORS," TO PROVIDE INFORMATION ON HAZARDOUS MOUNTAIN WINDS AND THEIR EFFECTS ON FLIGHT OPERATIONS NEAR MOUNTAINOUS REGIONS. THE PRIMARY PURPOSE OF AC 00-57 IS TO ASSIST PILOTS INVOLVED IN AVIATION OPERATIONS TO DIAGNOSE THE POTENTIAL FOR SEVERE WIND EVENTS IN THE VICINITY OF MOUNTAINOUS AREAS AND TO PROVIDE INFORMATION ON PREFLIGHT PLANNING TECHNIQUES AND IN-FLIGHT EVALUATION STRATEGIES FOR AVOIDING DESTRUCTIVE TURBULENCE AND LOSS OF AIRCRAFT CONTROL. I HAVE ENCLOSED A COPY OF THE AC FOR THE BOARD'S INFORMATION. 2. NOAA AND NCAR PERSONNEL COLLECTED DATA ON THE INTENSITY AND DIRECTION OF WIND FLOWS AT THE COLORADO SPRINGS AIRPORT DURING THE PERIOD JANUARY THROUGH MARCH 1997, WHEN MOUNTAIN-INDUCED ACTIVITY WAS KNOWN TO BE PREVALENT. A DATA SET WAS DEVELOPED THROUGH THE USE OF ONE DOPPLER LIGHT DISTANCING AND RANGING (LIDAR) UNIT; THREE WIND PROFILERS WITH RADIO ACOUSTIC SOUNDING SYSTEM; ANEMOMETERS; AN INSTRUMENTED KING AIRCRAFT THAT TRAVERSED THE LANDING AND TAKEOFF FLIGHT PATH; SIX SURFACE METEOROLOGICAL STATIONS; AN INFRASONIC LABORATORY; AND PILOT REPORTS. NOAA AND NCAR ARE PUBLISHING A REPORT ON THEIR FINDINGS. 3. NOAA AND NCAR WILL COMPLETE A REPORT BY SEPTEMBER 1998 ON LIMITED ANALYSIS OF THE COLORADO SPRINGS DATA. ONE OBJECTIVE OF THE ANALYSIS IS TO ASSESS THE TURBULENCE-DETECTION CAPABILITIES OF THE LIDAR AND GROUND ANEMOMETERS. A FURTHER OBJECTIVE IS TO DETERMINE THE STRENGTHS OF LIDAR-DETECTED WIND TURBULENCE AS A FUNCTION OF OTHER FACTORS THAT WERE RECORDED DURING THE EXPERIMENT. THE ORIGINAL SCOPE OF THE EXPERIMENT AT COLORADO SPRINGS THAT WAS ANTICIPATED IN RESPONSE TO A-92-57 AND -58 HAS BEEN REDUCED BECAUSE OF FUNDING CONSTRAINTS AND THE OVERALL ASSESSMENTS OF THE PRIORITY OF SAFETY-RELATED RESEARCH. AS A RESULT, THIS PROJECT HAS BEEN TERMINATED AT THIS POINT. HOWEVER, THE RESULTS OF WHAT WAS COMPLETED ARE IMPRESSIVE, ESPECIALLY AC 00-57. THIS AC PROVIDES TO THE PILOT COMMUNITY PRACTICAL INFORMATION ON THE POTENTIAL HAZARDS TO AIRCRAFT THAT RESULT FROM MOUNTAIN WINDS. THE SPECIFIC RESEARCH THAT WAS COMPLETED BY NOAA AND NCAR ON DATA GATHERED AT COLORADO SPRINGS IS IMPORTANT IN ASSESSING THE CAPABILITIES OF LIDAR AND GROUND ANEMOMETERS. WHILE THE FAA IS NOT ABLE TO CONTINUE THIS PROGRAM TO THE EXTENT ORIGINALLY PLANNED, I BELIEVE THAT THE WORK ACCOMPLISHED DOES SATISFY THE OVERALL INTENT OF THESE SAFETY RECOMMENDATIONS.

From: NTSB
To: FAA
Date: 3/20/1996
Response: LETTER TO THESE RECOMMENDATIONS. THE BOARD IS CONCERNED ABOUT THE PROGRAM REDUCTION & URGES THE FAA TO MAKE EVERY EFFORT TO INCREASE FUNDING FOR THIS PROGRAM. HOWEVER, THE REDUCED PROGRAM OUTLINED BY THE FAA DOES PARTIALLY SATISFY THE OBJECTIVES OF THE BOARD'S RECOMMENDATIONS. PENDING FURTHER INFO, THE BOARD CLASSIFIES A-92-57 & -58 "OPEN--ACCEPTABLE ALTERNATE RESPONSE."

From: FAA
To: NTSB
Date: 12/14/1995
Response: THE FAA IS CONTINUING ITS PLANS FOR THE DATA COLLECTION EXPERIMENT AT COLORADO SPRINGS. HOWEVER, IN LIGHT OF REDUCED FAA BUDGET ALLOCATIONS & EXPECTED CONTINUED FUNDING CONSTRAINTS, A REDUCED PROGRAM FROM WHAT WAS ORGINALLY PLANNED HAS BEEN DEVELOPED. FUNDS NECESSARY TO CONDUCT AN EXHAUSTIVE DATA COLLECTION EXPERIMENT BY THE NATIONAL OCEANIC & ATMOSPERIC ADMINISTRATION'S FORECAST SYSTEMS LABORATORY TO OBSERVE, DOCUMENT, & ANALYZE METEOROLOGICAL AIRCRAFT HAZARDS AROUND COLORADO SPRINGS TO UNDERSTAND FULLY THE SCIENCE OF THE PHENOMENA WERE REDUCED. THEREFORE, THE FAA PLANS TO COMPLETE THREE PRODUCTS: 1) A COSPONSORED FAA/NOAA PILOT TRAINING MANUAL ON THE IMPACT OF MOUNTAIN-INDUCED AERONAUTICAL HAZARDS ON AIRCRAFT OPERATIONS; 2) THE COLORADO SPRINGS DATA COLLECTION & BASELINE EXPERIMENT FOR A TERMINAL AREA DETECTION SYSTEM FOR MOUNTAIN-INDUCED TURBULENCE HAZARDS; & 3) A FINAL REPORT WITH DEVELOPING A PROTOTYPE PREDICATION, DETECTION & DISPLAY SYSTEM FOR THESE HAZARDS IN THE TERMINAL AREA. BASED ON THE RESULTS OF THE COLORADO SPRINGS BASELINE EXPERIMENT, ANALYSIS, & AVAILABLE FUNDING, THE FAA WILL CONSIDER CONTINUATION & EXPANSION TO OTHER MOUNTAINOUS AREAS AS WELL AS POTENTIAL DEVELOPMENT OF A TERMINAL AREA DETECTION & DISPLAY SYSTEM FOR MOUNTAIN-INDUCED TURBULENCE HAZARDS.THE FAA IS CONTINUING ITS PLANS FOR THE DATA COLLECTION EXPERIMENT AT COLORADO SPRINGS. HOWEVER, IN LIGHT OF REDUCED FAA BUDGET ALLOCATIONS & EXPECTED CONTINUED FUNDING CONSTRAINTS, A REDUCED PROGRAM FROM WHAT WAS ORGINALLY PLANNED HAS BEEN DEVELOPED. FUNDS NECESSARY TO CONDUCT AN EXHAUSTIVE DATA COLLECTION EXPERIMENT BY THE NATIONAL OCEANIC & ATMOSPERIC ADMINISTRATION'S FORECAST SYSTEMS LABORATORY TO OBSERVE, DOCUMENT, & ANALYZE METEOROLOGICAL AIRCRAFT HAZARDS AROUND COLORADO SPRINGS TO UNDERSTAND FULLY THE SCIENCE OF THE PHENOMENA WERE REDUCED. THEREFORE, THE FAA PLANS TO COMPLETE THREE PRODUCTS: 1) A COSPONSORED FAA/NOAA PILOT TRAINING MANUAL ON THE IMPACT OF MOUNTAIN-INDUCED AERONAUTICAL HAZARDS ON AIRCRAFT OPERATIONS; 2) THE COLORADO SPRINGS DATA COLLECTION & BASELINE EXPERIMENT FOR A TERMINAL AREA DETECTION SYSTEM FOR MOUNTAIN-INDUCED TURBULENCE HAZARDS; & 3) A FINAL REPORT WITH DEVELOPING A PROTOTYPE PREDICATION, DETECTION & DISPLAY SYSTEM FOR THESE HAZARDS IN THE TERMINAL AREA. BASED ON THE RESULTS OF THE COLORADO SPRINGS BASELINE EXPERIMENT, ANALYSIS, & AVAILABLE FUNDING, THE FAA WILL CONSIDER CONTINUATION & EXPANSION TO OTHER MOUNTAINOUS AREAS AS WELL AS POTENTIAL DEVELOPMENT OF A TERMINAL AREA DETECTION & DISPLAY SYSTEM FOR MOUNTAIN-INDUCED TURBULENCE HAZARDS.

From: NTSB
To: FAA
Date: 1/4/1994
Response: THE BOARD NOTES THAT THE FAA HAS ASKED THE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION'S FORECAST SYSTEMS LABORATORY TO ORGANIZE A PLANNING GROUP TO FORMULATE A PROGRAM PLAN TO PROVIDE A DEFINITIVE STUDY OF MOUNTAIN-INDUCED WIND PHENOMENA AND THEIR EFFECT ON AIRCRAFT IN FLIGHT, AND TO DEVELOP INITIATIVES TO DEFINE AND IMPLEMENT AN AWARENESS PROGRAM TO ALERT PILOTS TO THIS POTENTIAL HAZARD. PENDING FURTHER INFORMATION, THE BOARD CLASSIFIES RECOMMENDATION A-92-57 AND -58 "OPEN--ACCEPTABLE RESPONSE."

From: NTSB
To: FAA
Date: 10/13/1993
Response: From the aircraft accident report of the in-flight engine separation of Japan Airlines, Inc, flight 46E Boeing 747-121, N473EV in Anchorage, Alaska on March 31, 1993. The Board adopted this report on 10/13/1993. Additionally, the Safety Board reiterates Safety Recommendation A-92-58.

From: FAA
To: NTSB
Date: 9/14/1993
Response: THE FAA HAS TASKED THE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION'S FORECAST SYSTEMS LABORATORY TO: (1) ORGANIZE A PLANNING GROUP TO FORMULATE A PROGRAM PLAN TO PROVIDE A DEFINITIVE STUDY OF MOUNTAIN-INDUCED WIND PHENOMENA AND THEIR EFFECT ON AIRCRAFT IN FLIGHT; AND (2) DEVELOP INITIATIVES TO DEFINE AND IMPLEMENT AN AWARENESS PROGRAM TO ALERT PILOTS TO THIS POTENTIAL HAZARD. THE FIRST TASK WILL RESULT IN A DETAILED PLAN FOCUSING ON METHODOLOGY, SCIENTIFIC ANALYSIS, AND AN ASSESSMENT OF THE EFFECT MOUNTAIN-INDUCED WIND PHENOMENA ON AIRCRAFT IN FLIGHT. THE SECOND TASK WILL RESULT IN FIRST PHASE OF A LONG-TERM PILOT AWARNESS INITIATIVE. THIS PILOT AWARENESS INITIATIVE WILL INCLUDE EDUCATIONAL MATERIAL FOR INDUSTRY AND GENERAL AVIATION USERS AND A PRELIMINARY SCIENTIFIC DEFINITION OF THE PHENOMENA TO BE USED BY AIRCRAFT MANUFACTURERS AND COMMERCIAL AIRLINES IN TRAINING PROGRAMS, PARTICULARLY THOSE THAT USE SIMULATORS.

From: NTSB
To: FAA
Date: 6/10/1993
Response: THE BOARD NOTES THAT THE FAA'S RESEARCH & DEVELOPMENT SERVICE IS PLANNING TO IMPLEMENT IN FISCAL YEAR 1994 ITS INTERAGENCY PROGRAM WITH THE NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION/FORECAST SYSTEMS LABORATORY OR THE NATIONAL SCIENCE FOUNDATION/NATIONAL CENTER FOR ATMOSPHERIC RESEARCH. THE BOARD IS PLEASED THAT THE FAA WILL BEGIN A PROGRAM BY THE FALL OF THIS YEAR BECAUSE THE BOARD IS CURRENTLY INVESTIGATING FOUR ACCIDENTS IN WHICH MOUNTAIN-INDUCED METEOROLOGICAL PHENOMENA MAY BE A CAUSE OR FACTOR. FURTHERMORE, THE FAA PLANS TO WRITE THE PROGRAM PLAN & DEVELOP A PRELIMINARY PILOT AWARENESS PROGRAM IN FISCAL YEAR 1993. BASED ON THIS INFO, THE BOARD CLASSIFIES A-92-57 & -58 AS "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 3/26/1993
Response: THE FAA AGREES WITH THE INTENT OF THESE RECOMMENDATIONS. ON OCTOBER 8, 1992, THE FAA TOLD THE BOARD THAT WORK WOULD BEGIN ON THIS PROGRAM BY FISCAL YEAR 1995. THE FAA'S RESEARCH AND DEVELOPMENT SERVICE IS NOW PLANNING TO ACCELERATE THE IMPLEMENTATION OF THIS PLAN TO FISCAL YEAR 1994. THE FAA PLANS TO WRITE THE PROGRAM PLAN AND DEVELOP A PRELIMINARY PILOT AWARENESS PROGRAM IN FISCAL YEAR 1993. A SUCCESSFUL PROGRAM TO ALLEVIATE THE HAZARDS POSED BY THIS POTENTIAL METEOROLOGICAL PHENOMENON MUST INCORPORATE A NUMBER OF KEY COMPONENTS. FIRST, THE EVOLUTION AND BASIC DYNAMICS OF THE ATMOSPHERIC PHENOMENON MUST BE UNDERSTOOD AND MODELLED. THE RELATIONSHIP OF THESE ATMOSPHERIC DYNAMICS TO AIRCRAFT STABILITY, CONTROL, AND PERFORMANCE MUST ALSO BE CHARACTERIZED. SENSOR TECHNOLOGIES, BOTH GROUND-BASED AND AIRBORNE, CAPABLE OF DETECTING AND MEASURING THE PHENOMENON MAY THEN BE DEVELOPED AND INCORPORATED INTO A SYSTEM WHICH INCLUDES THE COMPLETE HAZARD INFORMATION FLOW TO BOTH THE FLIGHT DECK AND GROUND USERS. FINALLY, THE OPERATIONAL IMPACT AND SYSTEM REQUIREMENTS NECESSARY TO REALIZE FULLY THE BENEFITS ENABLED BY THESE SYSTEMS MUST BE ADDRESSED.

From: NTSB
To: FAA
Date: 12/8/1992
Response: THE BOARD NOTES THAT THE FAA AGREED WITH THE INTENT OF THESE RECOMMENDATIONS AND THAT IT PLANS TO ADDRESS THEIR INTENT THROUGHT AN INTERAGENCY PROGRAM WITH THE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION/FORECAST SYSTEMS LABORATORY OR THE NATIONAL SCIENCE/NATIONAL CENTER FOR ATMOSPHERIC RESEARCH. HOWEVER, THE BOARD IS CONCERNED THAT THE FAA BELIEVES THAT DUE TO BUDGET CONSTRAINTS AND PROGRAM PRIORITIES, THESE PROJECTS CANNOT BE STARTED UNTIL FISCAL YEAR 1995. THE BOARD UNDERSTANDS THE DIFFICULTY IN FUNDING THESE PROJECTS IN FISCAL YEAR 1993, BUT BELIEVES THAT THE FAA SHOULD REEVALUATE ITS PRIORITIES TO INCLUDE THEM IN 1993. PENDING FURTHER INFORMATION CONCERNING FISCAL YEAR 1993 FUNDING, THE BOARD CLASSIFIES RECOMMENDATIONS A-92-57 AND A-92-058 AS "OPEN --UNACCEPTABLE RESPONSE." From the United Airlines flight 585 Boeing 737-291, N999UA Uncontrolled Collision with terrain for undetermined reasons four miles south of Colorado Springs Municipal Airport in Colorado Springs, Colorado on March 3, 1991. The Board adopted this report on 12/8/1992. In addition, as a result of information developed during the course of this investigation, the Safety Board reiterates the following two safety recommendations that it issued on July 20, 1992, to the Federal Aviation Administration: A-92-57 and A-92-58.

From: FAA
To: NTSB
Date: 10/8/1992
Response: THE FAA AGREES WITH THE INTENT OF THESE RECOMMENDATIONS WHICH PROPOSE A TWO-PHASE PROGRAM TO OBSERVE, DOCUMENT, AND ANALYZE POTENTIAL METEOROLOGICAL AIRCRAFT HAZARDS. THE PROGRAM WOULD BEGIN IN THE AREA OF COLORADO SPRINGS, COLORADO, AND IF THE RESULTS SUPPORT ADDITIONAL STUDY, EXPAND TO OTHER MOUNTAINOUS AREAS. THE FAA'S RESEARCH AND DEVELOPMENT SERVICE IS PRESENTLY ADMINISTRATING THE INTEGRATED AIRBORNE WINDSHEAR RESEARCH PROGRAM WHICH WILL RESULT IN A STUDY ON THE APPLICABILITY OF AIRBORNE SENSORS TO DETECT CLEAR AIR TURBULENCE AND MOUNTAIN WAVE PHENOMENA IN FISCAL YEAR 1994. ADDITIONALLY, THE AVIATION WEATHER SERVICES IMPROVEMENTS PROGRAM IS CURRENTLY STUDYING A NUMBER OF WIND PHENOMENA; HOWEVER, NO SPECIFIC STUDY OF MOUNTAIN ROTOR IS IN PROGRESS. THE FAA HAS TWO APPROPRIATE CONTRACT MECHANISMS ESTABLISHED WHICH CAN BE USED TO ADDRESS THE SPECIFIC INTENT OF THESE RECOMMENDATIONS. THE EXISTING INTERAGENCY AGREEMENTS ARE WITH THE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION/FORECAST SYSTEMS LABORATORY AND THE NATIONAL SCIENCE FOUNDATION/NATIONAL CENTER FOR ATMOSPHERIC RESEARCH. THE FAA ANTICIPATES, BASED ON BUDGET CONSTRAINTS AND PROGRAM PRIORITIES, THAT THE WORK ON THESE PROJECTS COULD START IN FISCAL YEAR 1995.