Vulcan Aerospace intends to compete for smaller Defense Department launches after 2020 using its Stratolaunch carrier aircraft and multi-stage booster, company president Chuck Beames said Thursday.Beames said Vulcan believes it can fill a niche with the trend it sees toward smaller, disaggregated satellites. Beames said Vulcan recently sent a letter to the Air Force expressing its interest in competing for launches, educating the service on its eventual capabilities while asking the Air Force if it is interested in modifying future…