Three flight attendant unions voice alarm after 737 MAX hearings

CHICAGO (Reuters) - Unions representing flight attendants at the three U.S. airlines that operate Boeing Co's 737 MAX said they are more reluctant to support the grounded jet's return after congressional hearings this week on its development.Southwest Airlines and United Airlines flight attendant union leaders joined colleagues' demands for an active role in regulators' and airlines' decisions to let the 737 MAX fly again after two fatal crashes in Indonesia and Ethiopia. The two unions spoke..