Splash Pad

The marine spaceport for balloon-powered Spaceship Neptune, now closing in on commercial flight, is out of this world in its own right.

- Michael Verdon

MANY DESIGN PROJECTS have started with Lego building blocks, but the ship-based launch system for Space Perspective's Spaceship Neptune balloon and capsule is a most unique and remarkable example.

"We kept buying more boxes of them as we reconfigured the mock-up," says Taber MacCallum, who co-founded Space Perspective with his wife, Jane Poynter, in 2019 and serves as its chief technology officer.

The complex roller system aboard the Florida outfit's 294ft Marine Spaceport (MS) Voyager releases the 198m-long balloon and its passenger pod using a mere 61m of deck space. The enormous mechanised spools resemble a supersized Rube Goldberg machine, working with uncanny precision as they slowly unfurl-in a zigzagging process-the capsule's sole means of propulsion.

"The objective is to be very gentle with the balloon and not put any pressure points on it," says MacCallum during Robb Report's tour of the ship. A trace amount of hydrogen is injected into the tip of the balloon, and the rollers bring it vertical before it's tethered to the capsule on the stern. "We need just one per cent of lift gas, since hydrogen expands as it rises," explains MacCallum, adding that "by the time it reaches the apogee at 100,000ft, the balloon's fully inflated".

While the spool arrangement for deployment is certainly innovative, the ship itself is even more noteworthy as the aerospace industry's first marine spaceport for human flights. As such, the company has worked closely with the Federal Aviation Administration and the US Coast Guard to follow regulations for what is, essentially, a new type of vessel.