Four aircraft now control about 80 percent of the U.S.

Aircraft are a critical part of the economy, but for much of their history, the stock has been a terrible venture. Aircraft moves with financial cycles, and past downturns have caused different carrier liquidations and disappointments. But in a longer period of time, the merger arrangement made it easier for competitors to gather more successfully using innovation to oversee plans and set transitions. Four aircraft now control about 80 percent of the U.S. market.nasdaq read more