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Safety Recommendation Details

Safety Recommendation A-95-035
Details
Synopsis: ON 6/18/94, ABOUT 0625, A TRANSPORTES AEREOS EJECUTIVOS, S.A. (TAESA) LEARJET 25D, XA-BBA, CRASHED 0.8 NAUTICAL MILES SOUTH OF THE THRESHOLD OF RUNWAY 1R AT DULLES INTERNATIONAL AIRPORT (IAD), CHANTILLY, VIRGINIA, DURING AN INSTRUMENT LANDING SYSTEM (ILS) APPROACH IN INSTRUMENT METEOROLOGICAL CONDITIONS. ALL 10 PASSENGERS & BOTH CREWMEMBERS ABOARD WERE KILLED. THE AIRPLANE WAS DESTROYED BY IMPACT, & THERE WAS NO FIRE.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Require within 2 years that all turbojet-powered airplanes equipped with six or more passenger seats have an operating ground proximity warning system installed. (Superseded by A-99-036)
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action/Superseded
Mode: Aviation
Location: CHANTILLY, VA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA94MA061
Accident Reports: Controlled Collision with Terrain Transportes Aereos Ejecutivos, S.A. (TAESA) Learjet 25D, XA-BBA
Report #: AAR-95-02
Accident Date: 6/18/1994
Issue Date: 4/3/1995
Date Closed: 5/12/1999
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action/Superseded)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 7/13/1999
Response: ON 5/12/99, A-95-35 WAS CLASSIFIED "CLOSED--ACCEPTABLE ACTION/SUPERSEDED" IN OUR LETTER TRANSMITTING RECOMMENDATION A-99-36, WHICH SUPERSEDED A-95-35.

From: FAA
To: NTSB
Date: 5/4/1999
Response: Letter Mail Controlled 5/10/99 3:11:09 PM MC# 990495 ON 8/19/98, THE FAA ISSUED A NOTICE OF PROPOSED RULEMAKING (NPRM) PROPOSING TO REQUIRE THE INSTALLATION AND USE OF TERRAIN AWARENESS AND WARNING SYSTEM ON ANY U.S. - REGISTERED TURBINE-POWERED AIRPLANES WITH SIX OR MORE PASSENGER SEATS OPERATING UNDER 14 CFR PARTS 91, 121, AND 135. BECAUSE OPERATORS UNDER 14 CFR PART 125 AND OPERATORS OF U.S. - REGISTERED AIRPLANES UNDER 14 CFR PART 129 MUST COMPLY WITH 14 CFR PART 91, THEY WOULD ALSO HAVE TO MEET THE PROPOSED REQUIREMENTS OF THE NPRM. I HAVE ENCLOSED A COPY OF THE NPRM FOR THE BOARD'S INFORMATION. THE FAA IS ALSO ISSUING TECHNICAL STANDARD ORDER (TSO) C151, TERRAIN AWARENESS AND WARNING SYSTEM, WHICH PRESCRIBES THE MINIMUM OPERATIONAL PERFORMANCE STANDARDS THAT A TERMINAL AWARNESS AND WARNING SYSTEM MUST MEET. ON 11/4/98, THE FAA PUBLISHED A NOTICE OF AVAILABILITY FOR PROPOSED TSO C151, WITH A COMMENT PERIOD ENDING 1/26/99. THE FAA EXTENDED THE ORIGINAL COMMENT PERIOD FOR THE NPRM FROM 11/24/98, TO 1/26/99, TO COINCIDE WITH THE COMMENT PERIOD FOR THE TSO. I HAVE ENCLOSED A COPY OF THE DRAFT TSO FOR THE BOARD'S INFORMATION. I WILL PROVIDE THE BOARD WITH COPIES OF THE FINAL RULE AND TSO AS SOON AS THEY ARE ISSUED.

From: NTSB
To: FAA
Date: 2/26/1999
Response: Notation 7116: The National Transportation Safety Board has reviewed the Federal Aviation Administration's (FAA) Notice of Availability for Public Comment, Technical Standard Order (TSO) C151, "Terrain Awareness and Warning System," published in 63 FR 59494 on November 4, 1998, and the proposed TSO. The proposed TSO presents technical standards for the design of a terrain awareness and warning system (TAWS) that will be approved by the FAA. As a result of its investigation of the controlled flight into terrain (CFIT) accident that occurred on June 18, 1994, when a Transportes Aereos Ejecutivos, S.A. (TAESA) Learjet 25D crashed 0.8 miles south of the runway at Washington Dulles International Airport during restricted visual conditions, the Safety Board issued Safety Recommendation A-95-35 to the FAA. This recommendation asked the FAA to: Require within 2 years that all turbojet-powered airplanes equipped with six or more passenger seats have an operating ground proximity warning system [GPWS] installed. As a result of the December 20, 1995, CFIT accident involving an American Airlines Boeing 757 on a regularly scheduled passenger flight from Miami, Florida, to Cali, Colombia, the Safety Board issued Safety Recommendation A-96-101 to the FAA. This recommendation asked the FAA to: Examine the effectiveness of the enhanced ground proximity warning equipment and, if found effective, require all transport-category aircraft to be equipped with enhanced ground proximity warning equipment that provides pilots with an early warning of terrain. Accordingly, the FAA has proposed, in a notice of proposed rulemaking (NPRM) published in 63 FR 45627 on August 26, 1998, that TAWS be installed on all turbine-powered aircraft with 6 or more passenger seats. The Safety Board supports this action and believes that the NPRM, if promulgated, will have a positive effect on aviation safety by reducing the opportunities for CFIT accidents to occur. Consequently, the Board believes that this proposed rule is responsive to Safety Recommendations A-95-35 and A-96-101. As part of its rulemaking efforts, the FAA asked the Volpe National Transportation Systems Center (VNTSC) to evaluate the effectiveness of an enhanced GPWS (EGPWS) compared to the older GPWS. The results of the VNTSC evaluation showed that EGPWS was more effective than GPWS in providing pilots with additional time to avoid an imminent collision with terrain. The Safety Board believes that these results support the proposed requirement to install TAWS in air transport aircraft. However, as noted in the NPRM, the FAA recognizes that some pilots may inappropriately rely on TAWS for navigation. The Board strongly believes that a thorough human factors evaluation should be a routine aspect of the design and certification of new aircraft controls and displays-especially when the possibility for misuse exists. It appears that this possibility may not have been addressed in the context of a formal human factors evaluation. Although the Safety Board urges the FAA to proceed with this proposed TSO, it also recommends that the FAA monitor the use of TAWS and, if warranted, take appropriate corrective action for its design or use. Nonetheless, the Safety Board is pleased that the TAWS system is being deployed and anticipates that it will improve flight safety. The Safety Board appreciates the opportunity to comment on this proposed TSO.

From: NTSB
To: FAA
Date: 12/24/1998
Response: Notation 7101: The National Transportation Safety Board has reviewed your Notice of Proposed Rulemaking (NPRM), "Terrain Awareness and Warning System," which was published in 63 FR 45627 on August 26, 1998 The notice proposes to prohibit the operation of any turbine-powered aircraft with 1 or more passenger' seats, exclusive of the pilot and copilot seats unless that aircraft is equipped with a Federal Aviation Administration (FAA) approved terrain awareness and warning system (TAWS). The notice also proposes that, beginning 1 year after the effective date of the final rule, U.S.-registered airplanes manufactured after that date be equipped with TAWS; on all other aircraft, installation would be required within 4 years of the final rule's effective date. On June 18, 1994, about 0625 eastern standard time, a Transportes Aereos Ejecutivos, SA (TAESA) Learjet 25D crashed 0.8 nautical miles south of the threshold of runway 1R at Washington Dulles International Airport during restricted visual conditions. All 10 passengers and the 2 pilots were killed in the accident. The aircraft was not equipped, nor was it required to be equipped, with a Ground Proximity Warning System (GPWS). Safety Board analysis indicated that had a GPWS been installed on the aircraft, an aural mode 5, Descent Below Glideslope, warning would have been issued approximately 64 seconds before initial impact, at an altitude of 1,200 feet mean sea level (msl) and would have continued to the end of the flight. As a result of that accident, the Safety Board issued Safety Recommendation A-95-35 to the FAA: Require within 2 years that all turbojet-powered airplanes equipped with six or more passenger seats have an operating ground proximity warning system installed. On December 20, 1995, about 2142 eastern standard time, American Airlines (AAL) flight 965, a regularly scheduled passenger flight from.Miarni,Florida to Cali, Colombia, struck trees and then crashed into the side of a mountain near Buga, Colombia, in night, visual meteorological conditions, while descending into the Cali area. The airplane crashed 33 miles northeast of the Cali very high frequency omnidirectional radio range (VOR) navigation aid. The airplane was destroyed, and all but four of the 163 passengers and crew on board were killed. The investigation was conducted by the Aeronautica Civil of the Government of Colombia with assistance from the National Transportation Safety Board, in accordance with the provisions of Annex 13 to the Convention on International Civil Aviation. Assistance was also provided by the Federal Aviation Administration (FAA), AAL, the Allied Pilots Association, the Boeing Commercial Airplane Group, and Rolls-Royce, Inc., (the engine manufacturer). At 2141:05, about 104 seconds after the airplane had begun a right turn away from Cali, towards Bogota, Colombia, the airplane was descending through 8,839 feet msl, its airspeed was 240 knots indicated airspeed (KIAS), its descent rate was 1,400 to 1,500 feet per minute, its throttles were at idle, and its speedbrakes were fully extended. Eleven seconds later, while the airplane was passing through 8,571 feet msl, the ground proximity warning system (GPWS) began issuing aural warnings of "TERRAIN" and "PULL-UP." These warnings continued for 12 seconds, until 2141:28, the end of the recorded data. It is believed that had the airplane been equipped with TAWS, the pilots would have had notice of the impending collision with terrain considerably earlier than provided by the GPWS, and with the earlier warning they may have avoided the accident. Although the number of controlled flight into terrain (CFIT) accidents has decreased substantially since the FAA issued a requirement in 1975 to install GPWS on transport-category aircraft, the Safety Board believes that the frequency of CFIT accidents could be further reduced by employing recent technological advances such as enhanced GPWS (EGPWS). EGPWS or TAWS technology makes it possible to present terrain information on flight management system (FMS)-generated displays and weather radar displays by using a digital terrain elevation database and airplane three-dimensional position. The intended result is that pilots are provided with an earlier warning of potential terrain impact than on present GPWS-aircraft. Because this equipment may considerably reduce the potential for CFIT accidents thereby enhancing flight safety, the Safety Board issued Safety Recommendation A-96-10 1 to the FAA on October 16, 1996: Examine the effectiveness of the enhanced ground proximity warning equipment and, if found effective, require all transport-category aircraft to be equipped with enhanced ground proximity warning equipment that provides pilots with an early warning of terrain. The NPRM proposed rule is responsive to Safety Recommendations A-95-35 and A-96101 by proposing that TAWS be installed on all turbine-power aircraft with 6 or more passenger seats. The Safety Board supports this action and believes that the NPRM, if promulgated, will have a positive affect on aviation safety by reducing the opportunities for CFIT accidents. As part of its rulemaking efforts, the FAA asked the Volpe National Transportation Systems Center (VNTSC) to evaluate the effectiveness of an EGPWS compared to the older GPWS. The results of the VNTSC showed that EGPWS was more effective than GPWS in providing pilots with additional time to avoid an imminent collision with terrain. Notwithstanding these results, there is no evidence in the NPRM that the FAA solicited or performed a human factors evaluation of TAWS to determine its potential unintended effects on pilot performance. The NPRM, however, al1udes to such effects in the fol1owing excerpt: The TAWS topographical map display wil1 offer a temptation for pilots to use it for navigational purposes. Pilot training should emphasize that other aircraft systems are intended for this purpose, and any TAWS terrain display features are intended only to provide terrain awareness, not for aerial navigation. The Safety Board believes that standards for the TAWS design should be established to minimize the potential for subsequent misuse. Of equal importance, the Board also believes that pilot training programs should not be used to compensate for potential deficiencies in the TAWS design. For these reasons, the Safety Board believes that any requirement for TAWS should include a requirement that its design reflect the results of a thorough human factors evaluation to obviate the need for training and other procedural requirements that compensate for design deficiencies or misuse of design principles. On November 4, 1998, the FAA announced that it was seeking comments on a proposed Technical Standard Order (TSO) C151 on TAWS. The Safety Board plans to comment further about its concerns regarding the need to mitigate opportunities for misuse of TAWS technology when it responds to the notice of availability for public comment on TSO C151. The Safety Board appreciates the opportunity to comment on this proposed rule.

From: NTSB
To: FAA
Date: 7/31/1997
Response: The Safety Board has reviewed the results of the TSC study, which were issued in two memorandums. For the aircraft fleet operating under Title 14 Code of Federal Regulations (14 CFR) Part 91, the study concluded that the number of CFIT accidents would be dramatically reduced. Based on the potential savings of human life and economic benefits, the study urges the FAA "to implement NTSB Recommendation A-95-35," to "amend this recommendation to require installation of EGPWS," and that "the Data Source: NTSB Recommendations to FAA and FAA Responses NTSB recommendation be broadened by the FAA to installation of EGPWS," and that "the NTSB recommendation be broadened by the FAA to encompass all 'turbine powered' (i.e., not just turbojet) aircraft." The TSC study of the aircraft fleets operating under Parts 121 and 135 concluded that "EGPWS represents a major improvement in potential CFIT accident reductions," and that the FAA should amend 14 CFR Parts 121 and 135 with new rulemaking that would require mandatory installation of multicolor terrain display equipment such as that found in EGPWS. The TSC study fully supports action to revise 14 CFR Parts 91, 121, and 135 to mandate EGPWS on all turbine-powered airplanes with six or more passenger seats, and the Safety Board is pleased that the FAA has initiated rulemaking activity to accomplish this. Nearly a year has passed since the TSC study was completed; the Board hopes that this important rulemaking action is not delayed further. We look forward to receiving the notice of proposed rulemaking on this subject in the near future. Pending review of the final rule, the Safety Board has classified Safety Recommendation A-95-35 as "Open--Acceptable Response."

From: FAA
To: NTSB
Date: 4/17/1997
Response: The Federal Aviation Administration has initiated rulemaking proposing to mandate the installation of enhanced ground proximity warning systems (EPGWS) on all turbine-powered airplanes with six or more passenger seats. The FAA is also responding to a recommendation issued by the White House Commission on Aviation Safety and Security which urges the installation of EPGWS on commercial aircraft. The FAA is proposing to revise 14 CFR Parts 91, 135, and 121 to address both of these recommendations. I will provide the Board with a copy of any document that may be issued.

From: NTSB
To: FAA
Date: 8/29/1995
Response: THE BOARD NOTES THAT THE FAA HAS ORDERED A STUDY OF CONTROLLED FLIGHT INTO TERRAIN (CFIT) ACCIDENTS INVOLVING TURBOJET-POWERED AIRPLANES EQUIPPED WITH SIX OR MORE PASSENGER SEATS TO DETERMINE HOW MANY CFIT ACCIDENTS WOULD HAVE BEEN PREVENTED BY A GPFW. THE FAA WILL REVIEW THE DATA TO DETERMINE WHAT, IF ANY, REGULATORY ACTION NEEDS TO BE INITIATED. PENDING THE OUTCOME OF THE CFIT STUDY & THE FAA'S SUBSEQUENT ACTION, A-95-035 IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 6/14/1995
Response: THE FAA HAS ASKED THE TRANSPORTATION SYSTEMS CENTER TO CONDUCT A STUDY OF CONTROLLED FLIGHT INTO TERRAIN ACCIDENTS INVOLVING U.S. CERTFICATED TURBOJET-POWERED AIRPLANES EQUIPPED WITH SIX OR MORE PASSENGER SEATS. THIS STUDY WILL DOCUMENT THE CONTROLLED FLIGHT INTO TERRAIN ACCIDENTS THAT WOULD HAVE BEEN AVOIDED IF A GROUND PROXIMITY WARNING SYSTEM HAD BEEN INSTALLED. THE FAA WILL REVIEW THE RESULTS TO DETERMINE WHAT, IF ANY, REGULATORY ACTION NEEDS TO BE INITIATED. I WILL KEEP THE BOARD APPRISED OF THE FAA'S PROGRESS ON THIS RECOMMENDATION.