COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fokker F27 Series Aeroplanes
AD/F27/141 Main Landing Gear - Drag Stay Tubes 6/95
Applicability: All F27 aircraft with Dowty Aerospace Main Landing Gear Drag Stay assemblies P/N 200684001, 200261001, 200485001, 200684002, 200261002, 200485002,
200684003, 200261003 and 200485003 installed.
Requirement: 1. Ultrasonically inspect applicable assemblies to determine whether a straight or a stepped bore tube is installed. Inspect in accordance with Appendix A, paragraph 3 of Dowty Aerospace SB 32-82W or SB 32-169B as applicable.
Re-identify assemblies with a tube having:-
- a straight bore as P/N 200684004, 200261004 or 200485004 as appropriate,
b. a correctly blended radius as P/N 200684003, 200261003 or 200485003 as appropriate,
c. an incorrectly blended radius as P/N 200684002, 200261002 or 200485002 as appropriate.
Assemblies identified as P/N 200684004, 200261004 or 200485004 do not require further inspection.
2. Inspect Main Landing Gear Drag Stay assemblies re-identified as P/N 200684002, 200261002, 200485002, 200684003, 200261003 and 200485003 for cracking in accordance with Appendix A, paragraph 4 of Dowty Aerospace SB 32-82W or SB 32-169B.
Assemblies identified as P/N 200684003, 200261003 or 200485003 which have no crack indications do not require further inspection.
Re-identify assemblies identified as P/N 200684003, 200261003 or 200485003 with signal indications of less than 80% Full Screen Height (FSH) as 200684002, 200261002 or 200485002, as appropriate. Scrap assemblies with signal indications of 80% FSH or more.
3. Re-work assemblies 200684002, 200261002 and 200485002 in accordance with Appendix B of Dowty SB 32-82W Revision 1 or SB 32-169B Revision 1 as applicable. Inspect in accordance with Appendix A, paragraph 4 of Dowty Aerospace SB 32-82W or SB 32-169B as appropriate.
Re-worked assemblies P/N 200684002, 200261002 and 200485002 which have no crack indications shall be re-identified as P/N 200684003, 200261003, and 200485003 as appropriate; these assemblies do not require further inspection.
Scrap assemblies with any crack indications.
Note: RLD AD 93-169(A) refers.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Compliance: 1. Initially inspect and re-identify in accordance with Requirement 1 before 22 June 1995.
2. Initially inspect in accordance with Requirement 2 before 22 June 1995.
Re-inspect assemblies identified as P/N 200684002, 200261002 and 200485002 for cracking at intervals not to exceed 1500 flights until reworked in accordance with Requirement 3.
3. Re-work in accordance with Requirement 3 at, or before, the next scheduled Main Landing Gear overhaul after 25 May 1995, or before installation on an aircraft, whichever occurs later.
Background: One instance of a failed drag stay tube has been reported. Failure caused the landing gear to collapse and was attributed to a crack originating at an incorrectly machined step on the tube interior. This AD will ensure that all such tubes are identified and, if possible, reworked to an acceptable configuration.