A380 rear fuselage modification

A recent comprehensive mechanical and thermal load analysis of the A380
aeroplane fuselage Section 19 revealed a flange instability affecting Frame
(FR) 101, FR108 and FR110.
This condition, if not corrected, could affect the structural integrity of the
aeroplane.
To address this potential unsafe condition, Airbus developed production
modification (mod.) 73495, which reinforces the affected area, and issued
Service Bulletin (SB) A380-53-8085 and SB A380-53-8086, providing
modification instructions for in-service aeroplanes.
For the reasons described above, this AD requires modification of the affected
areas.

Required as indicated, unless accomplished previously:
Within 8 years since the aeroplane first flight, modify the cone/rear fuselage by
reinforcing of the structure on FR101, FR108 and FR110 in accordance with the
instructions of Airbus SB A380-53-8086 (for pre-mod 63221 aeroplanes) or SB
A380-53-8085 (for post-mod 63221 aeroplanes), as applicable to the aeroplane
configuration.