There's some pretty fundamental problems with spin launch.<p>Atmospheric drag is greatest at sea level, and drops as altitude increases. A traditional lift vehicle is traveling slowest during the early parts of its ascent, and starts reaching high velocity once it's cleared the thicker parts of the atmosphere. In contrast, spin launch is at its highest velocity (before the rocket engine ignites) right after it's released, so it's going to bleed off a lot of speed before it reaches the upper atmosphere.<p>Second, spinning exerts very heavy lateral Gs on the vehicle and load. This is not typical for space launch payloads, which are usually only designed to withstand vertical Gs. When the catapult releases the payload, atmospheric drag is going to put heavy vertical Gs on the payload. So a payload delivered through spin launch is going to have to withstand both lateral and vertical Gs.<p>Its an interesting concept, but I'm not sure if the advantages of this approach outweigh the disadvantages.<p>I do see a future use case for spin launchers based in vacuum, say, on the moon. Or maybe on Mars where atmosphere is much thinner.