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Safety Recommendation Details

Safety Recommendation A-96-115
Details
Synopsis: On March 3, 1991, at 0944 mountain standard time, United Airlines flight 585, a Boeing 737-291 airplane, crashed during an approach to the Colorado Springs, Colorado, airport. The crew of 5 and the 20 passengers were killed. The airplane was destroyed by the impact and a postcrash fire. The weather was clear with unlimited visibility. There were windshear reports during the day. At the time of the accident the surface winds were reported to be out of the northwest at 20 knots gusting to 28. The safety board has not determined the cause(s) of the accident and an investigation of airframe, operational and weather factors is continuing.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Require the modification of the input rod bearing on the B-737 series standby rudder actuator to prevent galling and possible discrepant operation of the rudder system by 8/1/97.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: COLORADO SPGS, CO, United States
Is Reiterated: No
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: 10/18/1996
Date Closed: 2/2/1999
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 2/2/1999
Response: THE FAA ISSUED AD 97-26-01, EFFECTIVE ON 1/20/98, TO REQUIRE REPETITIVE INSPECTIONS TO DETECT GALLING ON THE INPUT SHAFT AND BEARING OF THE STANDBY RUDDER POWER CONTROL UNIT (PCU); REPLACEMENT OF THE STANDBY RUDDER ACTUATOR, IF NECESSARY; AND THE INSTALLATION OF A NEWLY DESIGNED STANDBY PCU INPUT SHAFT BEARING WITHIN 3 YEARS OF THE EFFECTIVE DATE OF THE AD. BECAUSE THE FAA'S ACTION COMPLIES WITH THE INTENT OF A-96-115, IT IS CLASSIFIED "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 5/13/1998
Response: Letter Mail Controlled 5/18/98 3:54:43 PM MC# 980640 THE FAA HAS ISSUED AN AD FOR THE MODIFICATION OF THE INPUT ROD BEARING.

From: NTSB
To: FAA
Date: 7/15/1997
Response: A-96-115 ASKED THE FAA TO REQUIRE THE MODIFICATION OF THE INPUT ROD BEARING ON THE B-737 SERIES STANDBY RUDDER ACTUATOR TO PREVENT GALLING & POSSIBLE DISCREPANT OPERATION OF THE RUDDER SYSTEM BY 8/1/97. BOARD'S REVIEW OF THE FAA'S RULEMAKING ACTION, A-96-115 IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 1/16/1997
Response: ON 8/21/96, THE FAA ISSUED AN NPRM PROPOSING TO REQUIRE MODIFICATION OF THE INPUT ROD BEARING ON THE BOEING 737 STANDBY RUDDER ACTUATOR TO PREVENT GALLING & POSSIBLE DISCREPANT OPERATION OF THE RUDDER SYSTEM. THE FAA RECEIVED THE BOARD'S RECOMMENDATION AFTER THE COMMENT PERIOD CLOSED; HOWEVER, THE RECOMMENDATION WILL BE INCLUDED IN THE DOCKET & ADDRESSED IN THE COMMENT SECTION OF THE FINAL REGULATORY DOCUMENT. I WILL PROVIDE THE BOARD WITH A COPY OF THE FINAL REGULATORY DOCUMENT AS SOON AS IT IS ISSUED.