AD/B747/165 - Elevator Control System Modifications (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Boeing 747 Series Aeroplanes

AD/B747/165 Elevator Control System Modifications 2/97

Applicability: Model 747-200, -300 and -400 series aeroplanes, having cumulative line number (C/L) 696 through 1057 inclusive and equipped with Parker inboard elevator power control packages (PCP) having Part Number (P/N) 93600-5005 through -5051 inclusive, or P/Ns 327400-1001, -1003, 1005 and 1007; certificated in any category.

Requirement: 1. For Model 747-400 series aeroplanes, as listed in Boeing Alert Service Bulletin 747-27A2348, Revision 1, dated January 26, 1995, modify the hydraulic tubing of the right inboard elevator PCP in accordance with Boeing Alert Service Bulletin 747-27A2348, Revision 1, dated January 26, 1995.

2. For all applicable aeroplanes, modify the left and right servo assemblies of the inboard elevator PCP, in accordance with Parker Service Bulletin 327400-27-171, Revision 1, dated April 14, 1995, or Parker Service Bulletin 93600-27-173 dated May 17, 1995 as applicable.

Note: FAA AD 96-22-01 amendment 39-9790 refers.

Compliance: 1. Within 12 months of the effective date of this directive.

2. Within three years of the effective date of this directive.

This airworthiness directive becomes effective on 30 January 1997.

Background: The FAA has received a report of an uncommanded right elevator deflection after takeoff and reports of elevator/control column 'bumps' during the landing gear retraction cycle of these aeroplanes. The actions introduced by this Directive are intended to prevent uncommanded elevator deflection which could result in structural damage and reduced controllability of the aircraft.