The FAA has issued new and revised guidance to the aviation industry regarding development and implementation of Airworthiness Directives (ADs). Details on the new guidance were published in an FAA Special Airworthiness Information Bulletin (SAIB NM-11-53). The guidance stems from a serious problem that occurred in March and April 2008, when thousands of airline flights were cancelled due to what some believed may have been over-zealous scrutiny of some Southwest Airlines and American Airlines maintenance and inspection practices associated with AD compliance. Following these disruptions, the Department of Transportation “tasked an independent review team to examine the FAA’s safety culture and its implementation of safety management,” according to the SAIB. The FAA formed an AD compliance review team “to review the circumstances surrounding compliance issues with a specific AD, and the AD process in general.” An aviation rulemaking committee formed to evaluate and address the DOT and FAA team reports made recommendations to change FAA and industry guidance and training. According to the SAIB, “The deliverables and implementation actions are intended to improve the manufacturer development of service instructions, FAA AD development and oversight activities and operator planning, accomplishment and maintenance of service instructions incorporated by reference in ADs.”