By Aishwarya Nair and Eric M. Johnson (Reuters) -Boeing Co Chief Executive Dave Calhoun said on Friday the U.S. planemaker has no current plans to tap equity markets, and signaled a wait of at least two years before launching a new aircraft program. “There is no plan for an equity raise,” Calhoun told a conference organized by brokerage Bernstein. “I’m confident on the liquidity front. Cash flow is getting better every quarter. We’re at that stage now where we can start to quietly pay down debt.” Calhoun also said Boeing had received a “clear” response letter from the U.S. Federal Aviation Adm…