Orion (aka Multi-Purpose Crew Vehicle) has had a slow, expensive gestation costing several $billion so far, and its first crewed mission won't happen until at least 2021. How long? Its develioment stated the same year as SpaceX's Dragon. http://www.nbcnews.com/science/space/nasa-puts-orion-spaceships-parachute-its-toughest-test-n141296   Comparison (crew size) Orion (4) v Apollo (3) v Dragon V2 (7 - 2 decks)