Boeing is among the biggest gainers on the S&P 500 on Tuesday. Kevin Carter / Getty Images Close Major U.S. equities indexes gained ground on Tuesday, with tech stocks trending higher after a day of declines on Monday. The Dow Jones Industrial Average and benchmark S&P 500 gained 0.3% and 0.2%, respectively, and the tech-centric Nasdaq rose 0.4%. Boeing (BA) shares surged 8%, the leading gainers on the S&P 500 after the plane maker's new CFO said at a conference held by UBS that its plan to ramp up producti ...