By Valerie Insinna and David Shepardson WASHINGTON (Reuters) -Boeing issued a bulletin to its suppliers late last week that laid out practices to ensure bolts are properly torqued after multiple airlines reported loose hardware during inspections of the grounded 737 MAX 9, according to a memo seen by Reuters. The U.S. planemaker said that it is “imperative” that suppliers meet quality requirements, according to a Jan. 17 memo seen by Reuters, issued weeks after an accident when a panel ripped off of a 737 MAX 9 jet while in mid-air. “Ensure that work instructions are mistake-proof and quality …
