BREMEN, Germany – Development of spaceplanes for suborbital tourism, satellite launches and point-to-point terrestrial transportation are benefiting from advanced technology, panelists said at the Space Tech Expo Europe here.
“It was completely different 30 years ago,” said Koichi Yonemoto, co-founder and chief technical officer of Space Walker, a Japanese startup developing a suborbital spaceplane to launch satellites and, later, carry tourists. “At that time, everyone wanted to do single stage to orbit. To do that, you need a very efficient air-breathing engine. We did not have such an engine.”
The United Kingdom’s Reaction Engines is developing one, Synergetic Air-Breathing Rocket Engine (SABRE). Reaction Engine recently tested a key SABRE component, the precooler, at airflow temperature conditions as high as Mach 5.
“All our goals were achieved,” said Shaun Driscoll, Reaction Engines program director. “We are making progress and demonstrating these are viable technologies. We must continue to invest in them.”
The German space agency DLR has a concept for a vertical takeoff, horizonal landing spaceplane similar to the SpaceX Starship, said Martin Sippel, DLR head of mechanisms and products. “It can fly in 90 minutes to Australia and about one hour to West America or to East Asia,” he added.
In addition to point-to-point flights, Spaceliner could provide uncrewed transportation to low Earth orbit and flights to geosynchronous transfer orbit with an additional stage, Sippel said.
“The idea is to have mass production, like aircraft production, for reusable spacecraft,” Sippel said. “The Spaceliner and Starship could be launch vehicles and also serve a small portion of long-distance business travel.”
Polaris Spaceplanes, a DLR spinoff established in 2018, seeks to launch satellites and accommodate tourists on Aurora, a winged vehicle designed for horizontal takeoff and landing.
“Our vision is to make space travel like air travel,” said Polaris CEO Alexander Kopp. To do that, however, the startup will have to overcome technical and economic challenges. “It is very hard in Germany to find private investment for these kinds of projects,” Kopp said.
At the same time, panelists agreed that technology is helping reduce project costs.
“Clearly the technology is moving forward at an incredible pace,” Driscoll said, citing additive manufacturing as one of the technologies “enabling us to achieve things we could not have achieved years ago.”
Composite materials also help by reducing weight, Yonemoto said.