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 indicated the potential to reduce CFIT accidents by requiring the installation of a GPWS in turbojet-powered airplanes equipped with six or more passenger seats. The Board further stated that the 1996 DOT study provided compelling evidence that Safety Recommendation A-95-35 should be broadened to include turboprop-powered airplanes and require the installation of enhanced GPWS. As a result, the Safety Board classified Safety Recommendation A-95-35 "Closed--Acceptable Action/Superseded."

Enhanced GPWS for Transport-Category Airplanes (A-96-101)

On December 20, 1995, American Airlines flight 965, a Boeing 757, N651AA, was on a regularly scheduled 14 CFR Part 121 flight from Miami, Florida, to Cali, Colombia, when it struck trees and crashed into the side of a mountain in night VMC. Of the 8 crewmembers and 156 passengers aboard the airplane, all but 4 were killed. The airplane was equipped with a GPWS, as required. Approximately 12 seconds before impact, the GPWS began issuing aural warnings of "TERRAIN" and "PULL UP." However, the GPWS did not provide the warning in time for the flight crew to successfully avoid crashing into the mountainous terrain. As a result of this accident, the Safety Board issued Safety Recommendation A-96-101, asking 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.

On December 31, 1996, the FAA stated that it had begun evaluating the effectiveness of enhanced GPWS. Further, the FAA stated its belief that enhanced GPWS would perform as intended and should significantly increase a pilot's situational awareness. The FAA indicated that evaluations to date revealed that enhanced GPWS would be a valuable aid in preventing CFIT accidents. The FAA anticipated completing its evaluation by March 1997 and stated that it would initiate appropriate action based on the results of the evaluation.

On April 11, 1997, the Safety Board acknowledged that the FAA was considering the issuance of an NPRM to require enhanced GPWS equipment on all civil, turbinepowered aircraft with six or more passenger seats. The Board indicated that it would wait to review the FAA's final action.

On May 4, 1999, the FAA stated that, in August 1998, it issued an NPRM proposing to require the installation and use of TAWS on any U.S.-registered turbinepowered airplane with six or more passenger seats operating under 14 CFR Parts 91, 121, and 135. According to the FAA, because operators under 14 CFR Part 125 and operators