They're not a multi-stage gun because they are eschewing combustion entirely. ...
Quote from: edzieba on 08/16/2023 12:20 pmThey're not a multi-stage gun because they are eschewing combustion entirely. ...In the demonstrator they built they used compressed air. I suspect for a launch at orbital velocity they will use rocket propellants.
The company raised a $1.5 million pre-seed round in April 2023; now, nearly 18 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.
Can they build a 500 meter gun anywhere near that cheaply???
...My pain point is this: can people stop trying to re-solve launch and actually build the “things” these guys want to get into space?
S3 interviewed the team this weekend.
Quote from: Cheapchips on 09/29/2024 08:20 amS3 interviewed the team this weekend.At 13:00, they mention building a 15 km long gun with a Mach 25 exit velocity that can fire a 2 m diameter projectile, weighing 3000 kg, with a 500 kg payload into orbit.Aiming for launch in 2028-2029 in Northern Australia, as its relatively unpopulated and the gun will be really loud.
At 13:00, they mention building a 15 km long gun with a Mach 25 exit velocity that can fire a 2 m diameter projectile, weighing 3000 kg, with a 500 kg payload into orbit.Aiming for launch in 2028-2029 in Northern Australia, as its relatively unpopulated and the gun will be really loud.
Delivery Day is here, and we’re thrilled to bring this custom unit to Longshot Space Technologies Corporation in Tonopah, Nevada. This project is more than just a build; it’s a collaboration to pioneer affordable, innovative solutions for Earth and beyond. 🌍🚀This delivery marks another milestone in our mission to redefine what’s possible in sustainable, compact living. The work we’re doing with Long Shot Space not only aligns with our vision but opens up new avenues for the future of affordable housing.
Tonopah, located in the Nevada desert, presents extreme temperature swings between scorching hot days and chilly desert nights—conditions that demand durable, insulated, and adaptable spaces. Longshot Space will be using our 800 sq. ft. expandable container home to provide their team with a comfortable work environment during long testing days. With built-in climate control and durable materials, the container home offers respite from the heat while providing ample space for meetings, equipment storage, and rest.
Into the Nevada desertFor Longshot’s desert base, the team chose a milelong strip of land near the airport in 3,000-person Tonopah, Nevada, about halfway between Reno and Las Vegas. Since the airport is still in use and Longshot’s land is nearby, the company needs Federal Aviation Administration approval to start building its next guns. Nathan Saichek, Longshot’s chief technology officer and a longtime aerospace engineer, said the team plans to test subsections of its next, bigger pipe on private land nearby while they wait.First, Longshot plans to build what Grace called a “minigun,” measuring 30 inches in outside diameter. Once they build two smallish segments, making sure that pressure-firing works and the rig inside the tube speeds up right, they plan to expand it to about 1,800 feet long, or longer. Their hope, Saichek said, is that the 1,800-footer will propel a 220-pound object — closer to the weight of an average satellite than the Oakland gun’s 300-gram payloads — to Mach 5 and work as a hypersonic tester. Saichek called the next Nevada gun an “intermediate stepping stone,” necessary for testing and proof-of-concept before the company would procure the vast amounts of money needed to build a version long enough — likely more than 10 kilometers — to actually send something to space.
Join us for a live-streamed demonstration of Longshot’s revolutionary space launch technology. We’ll be firing our very own gas gun (at low pressure) followed by a live Q&A with the team behind the tech.[0:35:40] Low energy test shot occurs using Nitrogen gas.[1:35:00] Talks about building a 10-20 km long Mach 15-25 space gun in Australia.[1:40:10] Possibly launch large payloads into space within 6 years.Time Space Gun Name Length (km) Diameter (m) Projectile Mass (kg) Cost ($/kg) Acceleration (G) [1:53:10] Baby Bear152~3,000300-400 (100-150 with H2 recapture)200-300[1:53:10]Mama Bear~205~40,000>50N/A[1:54:20]Papa Bear~3510~800,000>10<200[1:56:40] 100 m/s delta-v needed to circularise payload's orbit, could use a cold gas thruster/solid motor.
Progress report: At an investor day last week, the team showed off a 70-ft long prototype that accelerates payloads to just past Mach 4. Now, they are building a 180-ft version suited for military hypersonics, with testing at speeds above Mach 5. Weapons researchers today might pay $6M to $8M to put materials or components in that environment, according to Grace, who said his company could do it for $150,000.If that works, the big leap is a 12-mile gun to send 100-kg payloads into orbit.
Probably better suited to launching materials into space from moon. Only need DV of Mach5-6 and payloads like water in metal canistor don't care about high Gs so barrel can be short.
Quote from: TrevorMonty on 06/24/2025 09:49 amProbably better suited to launching materials into space from moon. Only need DV of Mach5-6 and payloads like water in metal canistor don't care about high Gs so barrel can be short.On the Moon (or any other vacuum environment) they can omit the barrel entirely and just use guide rails for the projectile. Longshot's accelerator is not a pressure-based multi-chamber gun.
Quote from: edzieba on 06/24/2025 01:04 pmQuote from: TrevorMonty on 06/24/2025 09:49 amProbably better suited to launching materials into space from moon. Only need DV of Mach5-6 and payloads like water in metal canistor don't care about high Gs so barrel can be short.On the Moon (or any other vacuum environment) they can omit the barrel entirely and just use guide rails for the projectile. Longshot's accelerator is not a pressure-based multi-chamber gun. But it is pressure-based
Impingement of what? Pressure. I’m aware of the pinching mechanism. It’s still pressure, force over an area. A way to try to exceed the usual limits. But it is most certainly pressure.
Quote from: Robotbeat on 06/25/2025 03:28 pmImpingement of what? Pressure. I’m aware of the pinching mechanism. It’s still pressure, force over an area. A way to try to exceed the usual limits. But it is most certainly pressure.Well, at the rawest level its particle impact based. Using particles in a gas just makes handling much easier (and minimises erosion), but you could be firing small metallic pellets to the same effect.The key part is it's not propelled by a pressurised gas in an enclosure pushing a slug. No enclosure is required if your external environment is already a vacuum - the gas only needs to be directed from a nozzle to the passing projectile (which with correct nozzle design can be done through free space, as with every rocket with a de Laval nozzle), and once it impinges you don't care where it ends up afterwards, beyond preferring it to remain behind the projectile to minimise drag. This means you do not need a barrel to contain the gas, because gas containment is not a factor in the accelerator's operation. It also means you are not limited to the speed of sound in that gas, so you don't need to mess about with hot Hydrogen as in light-gas-guns.
Quote from: edzieba on 06/26/2025 10:47 amQuote from: Robotbeat on 06/25/2025 03:28 pmImpingement of what? Pressure. I’m aware of the pinching mechanism. It’s still pressure, force over an area. A way to try to exceed the usual limits. But it is most certainly pressure.Well, at the rawest level its particle impact based. Using particles in a gas just makes handling much easier (and minimises erosion), but you could be firing small metallic pellets to the same effect.The key part is it's not propelled by a pressurised gas in an enclosure pushing a slug. No enclosure is required if your external environment is already a vacuum - the gas only needs to be directed from a nozzle to the passing projectile (which with correct nozzle design can be done through free space, as with every rocket with a de Laval nozzle), and once it impinges you don't care where it ends up afterwards, beyond preferring it to remain behind the projectile to minimise drag. This means you do not need a barrel to contain the gas, because gas containment is not a factor in the accelerator's operation. It also means you are not limited to the speed of sound in that gas, so you don't need to mess about with hot Hydrogen as in light-gas-guns.Would mini-macron guns be potentially suitable for the impingment process?
I just don’t get the advantage over rockets. If you’re not recovering the gases, why not just use a rocket?
It just doesn’t matter that much that the gun is on the ground. There’s something analogous to the rocket equation for gun launch, and the rocket equation actually doesn’t bite for low delta-v. At low delta-v, the exponential is close to a linear relationship (remember conservation of energy is quadratic!).If you actually run the numbers, I don’t think you’d end up being any more efficient (in terms of volatiles mass and energy) with gun launch than rocket launch when discussing the low delta-v of the Moon, particularly if you’re not using a tube and therefore not recovering the volatiles.
It just doesn’t matter that much. If you look at the actual energy for gun launch and rocket launch, there’s no clear advantage to gun launch. Megajoules to Megajoules. And LOTS of drawbacks.
Cool announcement! Longshot just signed a lease with the City of Alameda for the use of an old Navy indoor cannon testing facility. It's like someone went back in time and tricked the Pentagon in building a space-gun development facility with a panoramic view of the SF Bay.Over the fall Longshot is going to be building the largest operational gun in the world (120' long 29" interior diameter. A tinker toy by my standards) at this facility before we move out the desert to build something not *embarrassingly insignificant*.If you want to see a quick walk though check out the video.
Progress continues on our space launch demonstrator, the K200! This is our first prototype designed to produce a sustained jet, at up to 10 MW for several seconds. Hydraulics for actuation, valve hydraulics, and fuel and probe lines have all been installed! This prototype is an essential stepping stone for determining jet scaling laws experimentally and for proving our kinetic launch concept.
[0:04:40] "Everytime you double the number of [gas] injections, the maximum pressure and temperature is cut by half." Max G-force applied to payload also cuts in half, so stretching the gun length makes launch gentler and cheaper materials can be used (steel/concrete).[0:05:20] Maximum pressure of the system is ~1,000 PSI.[0:13:20] 10-20 km gun will launch a payload at 150-250 Gs. Commercial electronics can survive 800-900 Gs.[0:14:30] Military electronics (e.g. guided weapons) can survive 40,000-60,000 Gs.[0:16:30] Starship is aiming for a "market price of $1,100 per kg" to orbit.[0:19:00] Minimal viable space gun would have a market price of ~$150/kg to orbit (500 kg payload). Aiming for "below $10" for future versions.[0:19:40] Most of the cost is electricity generation, so could go lower with cheaper solar panels or nuclear reactors.[0:20:20] 'Mama Bear' will fire a "20 ton bullet".[0:20:50] Currently building a 0.7 m diameter gun. [0:21:50] Existing gun hit Mach 4.2-4.5 using helium (built 2.5 years ago), could do Mach 6 if switching to hydrogen but not permitted at Oakland facility.[0:22:50] Material cost of gun is ~$40K, costs $5K per shot.[0:24:50] Big hypersonic market with DoD, $15 million rocket vs $150,000 using a gun (2 orders of magnitude).[0:26:10] Aiming for Mach 25, projectile heating is velocity3. Bigger projectiles are better (2 m diameter).[0:27:50] Needs to be over 150 kg projectile to reach orbit or will completely burn up from atmospheric friction.[0:28:40] A 2 ton projectile will lose ~50% mass from ablation. 20 ton vehicle needs 2 tons of ablative material to survive.[0:30:00] Mach 15 projectiles are well understood due to warhead heritage. Mach 25+ is unknown.[0:31:30] Sonic booms will be an issue, non elevated gun design was partly chosen for easier land procurement (and cheaper).[0:33:50] Air space issues are why Australia is a construction location vs USA (densest aircraft). Aiming for multiple launches per day. Alaska is also a possible location.[0:35:40] 'Papa Bear' gun is 7-8 m diameter, 70 km long and able to fire 100 ton projectiles (starship sized). Curvature of Earth becomes an issue.[0:38:40] The initial prototype gun was 12 m long, made of PVC, capable of Mach 1.8 and failed spectacularly.[0:40:10] Collecting telemetry is the current challenge (very short timeframes before it hits target).[0:41:10] Longshot have built 3 prototype barrel iterations.[0:43:50] New test location is an old Naval gun test facilty at Alameda Point with a 90 m long warehouse, been closed since the 1990s.[0:50:30] Competitor Spinlaunch has "blown through like $140 million" on a prototype to launch at Mach 1.6.[1:05:10] Air Force saved Longshot from bankruptcy.
An alternate approach... Wave Motion Launch Linkedin [Sep 2]
From $2,000/kg → $10/kg. Longshot’s accelerator gets material into space so much cheaper than traditional options, it’s redefining access to orbit.
We’ve been busy, but we secured our Alameda facility. A former Navy test hall now becoming home to Longshot’s next phase of hypersonic and space launch testing
Ever wonder what it takes to build a giant space gun? Same. So we went ahead and built one.
Go behind the scenes at Longshot’s Alameda facility for an inside look at the construction of our Mini-Gun test system. This build is a key step toward higher-frequency testing, faster iteration, and scalable ground-based launch technology. More to come.
Longshot is still awaiting NEPA approvals to begin work on a patch of land alongside the Tonapah regional airport near the town of Tonapah in Nye County, Nev., where it plans to build a much larger gun approaching a size that could get a payload into orbit.“The Nevada site is one-mile long, 100-ft wide, and would have a tube made of steel with a 3-ft interior diameter,” sys Grace. “It will stretch over half a kilometer, and would have multiple [gas injection] boosters along it.” Rather than rely on a single burst of energy to propel the payload, the Longshot method has smaller bursts of gas injected along the way. “So instead of one boom with all that temperature and pressure, we have pop, pop, pop all the way down. And the longer we can make it, the more gentle it can be.”Once approvals are secured, Grace says construction would involve a lot of the same materials and labor found in natural gas transmission. “Each injection [into the tube] is pressurized gas, so we’ll have a lot of nitrogen handling, hydrogen handling, big compressors. And in terms of material sourcing and flanging and welding, we expect it's the same kind of pipe welding you find in gas infrastructure.”Test firings so far have been into catch boxes and berms rather than going for launch distance, but the company is exploring obtaining permission to send a payload “to some altitude,” says Nathan Saichek, Longshot’s chief technology officer. The company has begun in-house designs for the Nevada facility, but Saichek says their aerospace expertise sometimes interferes with construction engineering tasks. “What we need is a civil engineer; aerospace engineers [like us] will over-engineer a concrete pad.”
Jan 14, 2026Longshot is rethinking access to space with wave-riding hypersonic vehicles that skip along the atmosphere like a stone on water. In this deep dive, the team explains how vehicle geometry, thermal protection, and advanced simulation tools come together to survive extreme heat, pressure, and forces on the path to Mach 25, and why this first-principles approach could change launch economics forever.
