COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 146 Series Aeroplanes AD/BAe 146/29 Seat Rail Bolts 3/91 Applicability: Model BAe 146 series 300 with the following constructors numbers: E3134, E3135, E3137, E3141, E3142, E3143, E3145, E3147, E3149, E3150 and E3151. Requirement: Action in accordance with Mandatory BAe 146 SB 53-102. Compliance: As specified in the Requirement Document. Background: To ensure that, if a higher density cabin layout is fitted in the future, the JAR and FAR crashworthiness requirements will still be met, it is necessary to ensure that the bolts securing the outer seat rails at frame 28 are changed from 1/4 in. to 5/16 in. diameter.