China’s aviation authority on Thursday issued an airworthiness directive on the Boeing Co 737 MAX that will help pave the way for the model’s return to service in China after more than two and a half years. The directive instructs airline operators on the revisions required before the MAX returns to service, although it does not specify when China will lift a ban on the MAX in its airspace. The Civil Aviation Administration of China (CAAC), which was the first regulator globally to ground the MAX in March 2019 after two deadly crashes, said it had completed a review of the design changes proposed by Boeing.