Aerospace companies are urging the United States to speed up a review of rule changes for airplane engines, warning delays in implementing planned global emissions standards could trigger industrial delays. The warning from the U.S. Aerospace Industries Association (AIA) comes as aerospace firms are more exposed to unexpected regulatory or economic hiccups following the COVID-19 crisis. The standards would curb the flow of potentially damaging soot particles and do not take effect until the start of 2023. But executives warn an already overstretched supply chain needs clarity long before then to avoid disruption. And they complain that a process involving two Washington agencies is moving too slowly, while Europe has already taken action. “Any delay to regulatory implementation would create uncertainty, potentially significantly impacting our supply chain, airline deliveries, and damage U.S. industry’s overall global competitiveness,” said Leslie Riegle, AIA assistant vice-president of civil aviation in response to a Reuters …