Boeing CEO Dave Calhoun faced bipartisan heat Tuesday as he sat for his first congressional testimony nearly six months after the door plug of a Boeing 737 Max 9 blew off during an Alaska Airlines flight in January. Calhoun, who announced in March he was stepping down at the end of the year, sought to assure senators his company was serious about improving its safety and quality practices amid ongoing investigations by the Justice Department and federal regulators. Two out of every three...