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Safety Recommendation Details

Safety Recommendation A-00-043
Details
Synopsis: ON 2/9/98, A BOEING 727, REGISTRATION NO. N845AA, OPERATING AS AMERICAN AIRLINES FLIGHT 1340, CRASHED SHORT OF THE RUNWAY WHILE ON A COUPLED INSTRUMENT LANDING SYSTEM (ILS) CATEGORY II APPROACH TO RUNWAY 14R AT CHICAGO O'HARE INTERNATIONAL AIRPORT (ORD). THE APPROACH WAS NORMAL UNTIL THE AIRPLANE PASSED THROUGH 200 FEET ABOVE GROUND LEVEL (AGL), WHERE THE AIRPLANE STARTED A PITCH OSCILLATION THAT GREW IN TIME. THE AIRPLANE DESCENDED BELOW THE ILS GLIDE SLOPE, THEN CLIMBED ABOVE IT, AND FINALLY DESCENDED BELOW IT AGAIN, IMPACTING THE GROUND 300 FEET SHORT OF THE RUNWAY THRESHOLD. UPON IMPACT, THE AIRPLANE SLID OVER THE THRESHOLD AND THEN OFF THE RIGHT SIDE OF THE RUNWAY, WHERE IT CAME TO REST. THE AIRPLANE WAS EXTENSIVELY DAMAGED, AND 22 PASSENGERS AND 1 FLIGHT ATTENDANT SUSTAINED MINOR INJURIES.
Recommendation: THE NTSB RECOMMENDS THAT THE FAA: ADVISE ALL OPERATORS OF BOEING 727 AIRCRAFT EQUIPPED WITH SPERRY AEROSPACE SP-50 AND SP-150 AUTOPILOTS TO INFORM THEIR PILOTS, MAINTENANCE, AND ENGINEERING PERSONNEL OF THE DANGERS OF CONDUCTING COUPLED INSTRUMENT LANDING SYSTEM APPROACHES AT AIRSPEEDS THAT ARE NOT CONSISTENT WITH THE DESENSITIZATION SCHEDULE OF THE AUTOPILOTS, AND NOTIFY THE OPERATORS THAT THE FEDERAL AVIATION ADMINISTRATION HAS BEEN ASKED TO DEVELOP OPERATING LIMITATIONS FOR THE USE OF THESE AUTOPILOTS ON COUPLED APPROACHES THAT WILL ENSURE THAT THE APPROACHES ARE CONDUCTED IN A MANNER CONSISTENT WITH THE AUTOPILOT DESIGN.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: CHICAGO, IL, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA98MA023
Accident Reports: Ground Impact of American Airlines 1340
Report #: AAB-01-01
Accident Date: 2/9/1998
Issue Date: 6/1/2000
Date Closed: 11/26/2001
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Autopilot, Flightcrew, Maintenance, Training and Education

Safety Recommendation History
From: NTSB
To: FAA
Date: 11/26/2001
Response: On June 13, 2001, the FAA issued Flight Standards Information Bulletin for Air Transportation (FSAT) 01-04, General Aviation (FSGA) 01-01, and Airworthiness (FSAW) 01-05, titled "Autopilots on Boeing 727 Aircraft and Other Aircraft." The bulletins direct principal operations inspectors (POIs) whose air carriers are equipped with time-based desensitization-scheduled autopilots, including the Sperry Aerospace SP- 50 and SP-150, to request that their carriers inform their pilots, and maintenance and engineering personnel, of the dangers of conducting coupled instrument landing system approaches at airspeeds that are not consistent with the autopilot desensitization schedule. The bulletins include guidance to ensure that proper airspeeds are flown in accordance with time-based desensitization schedules and directs POIs to advise their operators that the FAA will develop operating limitations for the use of these autopilots on coupled approaches that will ensure that the approaches are conducted in a manner consistent with the design of the autopilot. Issuance of FSAT 01-04, FSGA 01-01, and FSAW 01-05 fully satisfies the intent of these recommendations. Accordingly, Safety Recommendations A-00-43 and -45 are classified "Closed--Acceptable Action."

From: FAA
To: NTSB
Date: 7/30/2001
Response: Letter Mail Controlled 08/09/2001 6:26:52 PM MC# 2010632: On June 13, 2001, the Federal Aviation Administration (FAA) issued Flight Standards Information Bulletin for Air Transportation (FSAT), General Aviation (FSGA), and Airworthiness (FSAW) Number FSAT 01-04, FSGA 01-01, and FSAW 01-05 entitled "Autopilots on Boeing 727 Aircraft and Other Aircraft." The bulletin directs principal operations inspectors (POI) whose air carriers are equipped with time- based desensitization scheduled autopilots, including the Sperry Aerospace SP-50 and SP-150, to request that their carriers inform their pilots, maintenance, and engineering personnel of the dangers of conducting coupled instrument landing system approaches at airspeeds that are not consistent with the autopilot desensitization schedule. The bulletin includes guidance to ensure that proper airspeeds are flown in accordance with time-based desensitization schedules. The bulletin directs POI's to advise their operators that the FAA will develop operating limitations for the use of these autopilots on coupled approaches that will ensure that the approaches are conducted in a manner consistent with the design of the autopilot. I have enclosed a copy of the bulletin for the Board's information. I consider the FAA's action to be completed on these safety recommendations.

From: NTSB
To: FAA
Date: 11/13/2000
Response: The FAA will issue a flight standards information bulletin directing its principal operations inspectors (POI) whose air carriers are equipped with time-based desensitization scheduled autopilots, including the Sperry Aerospace SP-50 and SP-150, to request that their carriers inform their pilots, maintenance, and engineering personnel of the dangers of conducting coupled instrument landing system approaches at airspeeds that are not consistent with the autopilot desensitization schedule. This bulletin will include guidance to ensure that proper airspeeds are flown in accordance with time-based desensitization schedules. The bulletin will also direct POIs to advise their operators that the FAA will develop operating limitations for the use of these autopilots on coupled approaches to ensure that the approaches are conducted in a manner consistent with the autopilot's design. The actions being taken by the FAA are responsive to the recommendations. Pending issuance of the flight standards information bulletin, Safety Recommendations A-00-43 and A-00-45 are classified "Open-Acceptable Response."

From: FAA
To: NTSB
Date: 8/9/2000
Response: Letter Mail Controlled 08/14/2000 3:27:27 PM MC# 2001057 The FAA agrees with the intent of these safety recommendations. The FAA will issue a flight standards information bulletin directing its principal operations inspectors (POI) whose air carriers are equipped with time-based desensitization scheduled autopilots, including the Sperry Aerospace SP-50 and SP-150, to request that their carriers inform their pilots, maintenance, and engineering personnel of the dangers of conducting coupled instrument landing system approaches at airspeeds that are not consistent with the autopilot desensitization schedule. The bulletin will include guidance to ensure that proper airspeeds are flown in accordance with time-based desensitization schedules. The bulletin will direct POI's to advise their operators that the FAA will develop operating limitations for the use of these autopilots on coupled approaches that will ensure that the approaches are conducted in a manner consistent with the design of the autopilot. It is anticipated that the bulletin will be issued by October 2000.