Winged heavier-than-air machines can exist without propulsion, but they won't be aircraft that can fly. The blockchain is analogous to wings on an aircraft. It'

Winged heavier-than-air machines can exist without propulsion, but they won't be aircraft that can fly. The blockchain is analogous to wings on an aircraft. It's a means to an end, not an end to itself. Bitcoin (the currency) is the propulsion, that when combined with the blockchain, allows distributed consensus (flight) to occur.