AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section. BAe Systems (Operations) Jetstream 4100 Series Aeroplanes AD/J4100/7 Cargo Doors 4/2008 DM Applicability: All Model Jetstream Series 4100 aircraft that are post modification JM41036B or which have Service Bulletin J41-53-008 (Mod JM41036A) accomplished. Requirement: Action in accordance with BAe Regional Aircraft Mandatory Service Bulletin J41-52-060 original issue, or later CAA/EASA approved revision. Note: UK CAA AD 005-08-98 refers. Compliance: For Part 1 of the Requirement document: Unless already accomplished, within 30 days after 20 February 2008; thereafter whenever a failed counter-balance motor is identified by Part 2 of the Requirement Document. For Part 2 of the Requirement document: Unless already accomplished, within 30 days after 20 February 2008, and thereafter at intervals not to exceed 5 days. A failed counter-balance motor must be replaced or repaired within 10 flights. This Airworthiness Directive becomes effective on 20 February 2008. Background: The manufacturer received a report of damage to a sub-frame that supports the bottom aft roller of the main baggage bay door. The sub-frame is primary structure of the door and failure of the sub-frame could allow other structure to fail. Failure of the door structure could cause a sudden loss of cabin pressure. David Villiers Delegate of the Civil Aviation Safety Authority 15 February 2008