Why use a rocket when you could use a giant, miles-long “gun” instead?
That’s the question posed by Longshot Space, a company that’s completely rethinking how to send mass to orbit. The company is developing a kinetic launch system that will gradually accelerate payloads to hypersonic speeds before launching them to orbit. While Longshot’s full-scale system will take up a lot of space, the startup is betting it can achieve very, very low costs to orbit compared to a rocket – as low as $10 per kilogram, which is a staggering reduction compared to the $6,000 per kilogram price of a ride-share on a SpaceX Falcon 9 rocket.
The company raised a $1.5 million pre-seed round in April 2023; now, nearly eighteen months later, Longshot closed a little over $5 million in combined venture funding and non-dilutive funding from the U.S. Air Force’s TACFI program. The new capital will be used to build a massive, 500-meter-long gun in the Nevada desert to push 100 kilogram payloads to Mach 5.
The move to Nevada is needed; Longshot has built out a prototype from its facilities in Oakland, California, but a dense, urban location is not the best place to site increasingly large space guns. The Oakland prototype hit 4.6 Mach speeds, but going any faster will mean a longer tube and the use of highly combustible hydrogen gas.
“We’d prefer not to blow ourselves and other people up,” Longshot CEO Mike Grace said in a recent interview. “We decided to just declare victory and withdraw at Mach 4.6.”
The mile-long strip of land in Tonopah, Nevada — a town that is home to the world-famous Clown Motel, as well as the development of the secretive B-17 stealth bomber, Grace said — will enable Longshot to demonstrate launch capability to prospective customers, including the U.S. Department of Defense.
Longshot’s architecture works in two ways: the first is by using an accelerant gas to push a plate (and the payload) forward using multiple injections, and by squeezing the payload from the sides. But the company will be able to get to upwards of Mach 7 speeds without any squeezing, so this first system in Nevada will just be a multi-injection gun with a 30-inch diameter, so the company can start moving payloads as quickly as possible.
The system has to be so long in order to keep acceleration forces low, which is better for both the vehicle and payload. Longshot is aiming to keep the maximum gravitational forces to 500-600 times the force of gravity. A ultra-long system, something that’s around 25 kilometers, could bring those g-forces down to just 250 G’s, however.
The company’s aim is not to replace propulsive rockets. Not all payloads are suitable for the high-G forces, let alone humans; the size of the tube will also always be smaller than larger rocket fairings, so Longshot is principally looking for customers who want to go cheap and rugged. For comparison, rocket launches exert around 3 G’s during take-off, so this is much, much more gravitational force. But it’s still far less than other kinetic launch systems, like that proposed by SpinLaunch, which would accelerate payloads to upwards of 10,000 G’s.
The new round included participation from Starship Ventures and Myelin VC. With the funding complete, Longshot is now awaiting approvals from the Federal Aviation Administration to begin construction on the massive Nevada system. The startup also submitted a proposal under the DOD’s Multi-Service Advanced Capability Hypersonics Test Bed MACH-TB program, which was established in 2022 to solicit hypersonic testing capabilities from private industry.
