When the ULA Vulcan was first announced, the plan was the engines, which are 90% of the cost of the first stage, would be recoverable and reusable. The idea was the engine section would detach from the rest of the rocket, fall a ways and then a parachute would open, and finally it would be caught mid-air by a helicopter. The idea was this would help it compete on price with the Falcon 9.<p>However, according to the Wikipedia article on Vulcan, this has not been funded, and so the rocket is going to be fully disposable.