Document ID: chunk:federal_register_of_legislation:F2006B02677:body:0:p2
Version: federal_register_of_legislation:F2006B02677
Segment Type: other
Provision Reference: 
Character Range: 2866–5936

2 of this Directive constitutes terminating action for the Requirement 1 inspections, and constitutes an acceptable alternative method of compliance with Paragraph F of FAA AD 91-06-06 (AD/B727/116 Amdt 1) for the affected area.
 COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
 SCHEDULE OF AIRWORTHINESS DIRECTIVES

           Contrary provisions of AD/B727/116 Amdt 1 notwithstanding, this Directive allows continued operation of the subject aircraft following the effective date of this Directive in accordance with the terms of this Directive, provided that the modification required by AD/B724/116 Amdt 1 has been accomplished on all lap joints other than those in the area of the main deck cargo door.

           Note 3: FAA Telegraphic AD T98-23-51 refers.

             Compliance: 1. Within 60 landings after 9 December 1998; thereafter at intervals not to exceed 60 landings until the Requirement 2 modification is accomplished.

             2.    At the latest of the following compliance times:

                1. Before the accumulation of 28,000 total landings.

b.    Within 250 landings after 9 December 1998.

c.    Within 120 days after 9 December 1998.

           This Airworthiness Directive becomes effective on 9 December 1998.

           Background: The FAA recently received information that the modification required by AD 91-06- 06 may not have been accomplished completely on as many as 160 aircraft that are included in the applicability of that AD and that are subject to the unsafe condition addressed in that AD. These aircraft were converted from a passenger-carrying to a cargo-carrying (freighter) configuration, or to a passenger-and cargo-carrying (combi) configuration. These conversions included installation of a main deck cargo door.
           Although these conversions were accomplished in accordance with several different Supplemental Type Certificates (STC), in each case, as part of the modification, a doubler (approximately 20 feet long) was installed over lap joints S-4L, S10L, S-19L, and (sometimes) S-26L.

           FAA personnel recently examined five of these aircraft, operated by three operators, and determined that the lap joints had not been modified, as required, in the area covered by the doublers on any of the five aircraft. Preliminary inquiries indicate a substantial likelihood that very few of the freighters or combi aircraft have been so modified. The installation of doublers over the lap joints during the freighter or combi conversions did not correct the unsafe condition addressed by AD 91-06-06 because it is not effective in preventing delamination, corrosion, and cracking in the lap joint. In fact, in some cases, the unsafe condition may be aggravated because of load redistribution due to installation of a main deck cargo door. This may accelerate crack growth along the lap joint under the doubler.

           It is possible that these lap joints have been neither inspected nor modified as required by AD 91-06-06, and