Raytheon discloses future lasers that can stop hypersonic missiles
defence-blog.com
defence-blog.com
As in "mirrors".
The BIG SECRET of directed energy weaponry is that there's a very simple and cheap method of reducing absorbed energy by orders of magnitude - reflect it in arbitrarty directions (or even towards the source if one wants to be naughty).
The sensors (which have to absorb EM radiation to function) are vulnerable, but can be easily protected by shutters for the duration of attack. Modern inertial navigation units are well capable of providing precise guidance without any external data.
Hope they have enough time to aim in the same spot.
But, I am very much an "airchair" weapons technologist so I'd be interested in seeing arguments for the contrary!
What about atmospheric interference? (And whatever unfortunate soul might be behind the missile assuming the laser misses.)
The field of wavefront adaptive optics[2] was a major civilian-side outcome of that work, with eventual impacts on human vision correction (e.g. LASIK, esp. for people w/ major astigmatism) and ground-based astronomy.
[1] https://en.wikipedia.org/wiki/Strategic_Defense_Initiative
[2] https://en.wikipedia.org/wiki/Adaptive_optics#Wavefront_sens...
That's really neat! I'm a beneficiary of this - with both nearsightedness and major astigmatism, I was told by the ophthalmologist that did my intake for LASIK that there was a non-trivial chance that the surgeon would decline to perform my operation (luckily he was in a confident mood). I went from completely non-functional without glasses to seeing 20/20 in one eye and 20/15 in the other.
While the benefits are diffuse, it's easily one of the top most impactful experiences in my life. It's akin to the feeling of successfully refactoring away a mountain of legacy tech debt that had been getting the job done but bogging you down. Getting rid of the tech debt feels great, but removing the cognitive load of even having to factor it into any decisions anymore just makes things more pleasant.
It's interesting to learn that, indirectly, I owe that to Regan's defense spending.
In-between, it is over 100km high up (ICBMs reach heights of >1000km. https://en.wikipedia.org/wiki/Intercontinental_ballistic_mis...)
An ICBM also likely isn't going to be above my territory when the propellant drops. After that the tiny missile heads are going to be very hard to hit. That's why you need these laser systems in space (the "Star Wars" program) so you can hit them right after launch.
Lastly, the risk of "dropping radioactive waste" is far lower than the risk of having a nuclear warhead detonate at its target destination.
Countries do missile tests. Some of them do not announce them because they want to avoid embarrassment when it doesn’t launch or goes boom.
If you attack any launch that looks like an ICBM, you will attack those, too, certainly if you want to down it “right next to where it launched”, as that gives you a very short time to decide whether the missile is armed with nuclear explosives.
I think that what you say comes down to that you’re willing to risk war to deny countries of doing any ICBM missile test.
> I think that what you say comes down to that you’re willing to risk war to deny countries of doing any ICBM missile test.
"Accidentally" shooting down an unannounced ICBM out of precaution is not necessarily an act of war, nor will it necessarily lead to war.
Huh, and here I thought the Hollow Earth theory had been discredited, but I guess I might believe Raytheon and its lasers. Cyrus Teed would be so pleased.
As an example, if you're at the North Pole and the South Pole base fires a ballistic missile at you, you can't aim a laser at it, as it would diametrically intersect the Earth.
Instead, you have to wait until the missile passes your horizon. The point at which it does this depends on its altitude. Hypersonic vehicles attempt to make interception harder by reentering the atmosphere from space earlier than a traditional ICBM, and travelling at a lower altitude in their final phase.
No, on a sphere a laser shot towards the horizon will not hit the Earth's "curves."
Shooting towards the horizon is by definition shooting tangentially to the surface you are on. The horizon is the point where the sky meets the land or sea. If you make a straight line from your laser to the horizon, it will continue out into space.
Your explanation of what they meant makes sense: a laser shot towards a distant target, not towards the horizon. But that's not what they said. And, obviously, I did not actually think the fault was the engineers' but the journalist's explanation.
It's certainly an issue when that "other" side is the outside.
Also, it's not like you're going to see the bullet hitting your head, or the landmine that'll blow you up, or the IED that you tripped over. Not until it's too late, anyway.
Sounds like Raytheon is taking the page about concept cars from the car industry and talking about totally conceptual products like they've already shipped.
The challenge with an ABM laser weapon system is generating enough power on-target that it's not just a rounding error for the energy that needs to be dissipated anyway. A quick back-of-the-envelope physics calculation indicates that'll be hard. An 80kg warhead is moving at about 5000 m/s upon re-entry and has a kinetic energy of about 1 GJ. I dunno what fraction of that kinetic energy is converted into thermal energy upon re-entry; for manned spacecraft it's "almost all of it" because they need to go subsonic for parachutes to deploy, but for ballistic missiles, let's guess 1/1000th for ease of math, or 1 MJ. Current laser weapons systems have a range of about 1mi (and the range of lasers is heavily limited by atmospheric considerations - atmospheric refraction will reduce your accuracy, while heating of water vapor, dust, and air can sap the energy). That's about 1/3 of a second on target, so the power output needed is about 3 MW. Current laser weapon systems like the AN/SEQ-3 have a power output of about 30 kW. This needs to scale up by a factor of 100 under conservative assumptions.
Like the article said, the solution to many of these issues is to put the lasers in space and intercept missiles in the boost phase. Then they're moving slower, you're targeting volatile fuel & oxidizer instead of heat shields, and you don't have atmospheric losses to worry about. You do have the issue of how to loft a giant laser, capacitor, and energy source into orbit, though, and how to protect them up there when a conflict starts.
Think of it this way, the shuttle could not dissipate massive energy on the 'top' because re-entry involved air over the bottom.
As for power rating, the Boeing High Energy Lasers were demonstrating effective missile defense in 2017[1], they were ramping up their power levels pretty quickly.
I see the biggest impact early on being fleet defense against hyper-sonic anti-ship missiles rather than ABM defense. Basically a CWIS replacement since it doesn't help to lose your $10B aircraft carrier to a $100M missile.
[1] https://www.boeing.com/defense/missile-defense/directed-ener...
I think the biggest impact is actually against low-tech threats: swarms of fast attack suicide boats, or 1960s-era cruise missiles that have ended up on the black market. There's a big cost advantage to being able to take these out with a quick 30kW pulse rather than a million-dollar missile, particularly since the threat itself probably cost less than a million dollars.
In a great-power conflict (where "great-power" is rapidly expanding to include private multinational corporations) the U.S. military is fucked anyway, but then, so is the opposing power. Perhaps that's the best we can hope for, because it's a pretty strong incentive not to start great-power conflicts in the first place.
Yes. That is indeed the concept of a (nuclear) deterrent.
Could the targeting system of the platform not consist of some kind of movable/adjustable prism that could acquire a target not just straight down on Earth's surface but also in other directions?
Such a system (if feasible) could probably also cut down hugely on time needed for and the amount of repositioning the weapons platform has to do during operation (thinking about and writing this sentence made the image of Tony Starks basement particle accelerator appear in my head again).
Edit: the referenced scene of Iron Man 2 https://www.youtube.com/watch?v=mBgUsKd0cuI&t=2m25s
Compensating for damaged control surfaces isn't impossible in all cases though, for the most part, fly-by-wire systems are servomechanisms which will scale their responses until the desired feedback is produced.
Most hypersonic weapons already require ablative materials to transit the atmosphere without disintegrating. Ablative shielding is the norm. Even then, a lot of engineering goes into ensuring that ablative loading is carefully controlled during flight -- any significant deviation from the designed ablative loading will cause catastrophic failure. It took decades of research to get to the point where a (non-ballistic) hypersonic missile under normal flight conditions could reliably manage the ablative loading long enough to reach its target. They are literally testing the theoretical limits of material physics.
Massively increasing the external thermal loading of those materials during flight is a great way to kill a hypersonic vehicle. It directly attacks one of their most vulnerable design constraints.
Missile defense has been in development for decades, and it never works. By the time it does, missiles will look like cross-bow bolts on the warfare menu.
Military spending is the elephant in the economy.
I could picture planes in the air 24-7 circling around vulnerable points, or being dispatched on warning. Either way it would be expensive but would be awesome.
The US previously spent a few billion and 16 years on that exact idea as part of the SDI, before canceling it a few years after the first working tests because, to quote the Defense Secretary,
>I don't know anybody at the Department of Defense who thinks that this program should, or would, ever be operationally deployed. The reality is that you would need a laser something like 20 to 30 times more powerful...there's nobody in uniform that I know who believes that this is a workable concept[0]
If the laser power was a problem, maybe Raytheon's tech will make the concept more plausible. The wikipedia article says there's been some additional experimentation mounting lasers on UAVs since the program was cancelled.
The ballistic warhead has little more to do than absorb the heat of reentry in the terminal phase. The energy to destroy it would be a good fraction of the energy that was in the rocket to begin with.
The hypersonic weapon on the other hand has to have sensors, effectors, and be unable to complete it's mission after receiving less beamed energy.
The airborne laser was killed not because it wasn't powerful enough (for some mission) but because the chemical laser it used was dangerous, expensive and otherwise impractical. The air force knew the army was developing modular fiber lasers so they decided to wait for that before building another platform, which could also be used against everything from drones to small ballistic missiles.
Hypersonic is just the cherry on top.
The alternative for interception hypersonics would be the nuclear-tipped ABMs of old, since the maneuvering capability of hypersonics defeats "hit-to-kill".
If you have a 99% chance of stopping a missile, but your adversary has tens or hundreds of thousands of missiles to fire at you, those aren't great odds.
Plus in a pinch, modern societies could probably come up with some fairly hideous deterrent weapons that didn't require missile delivery.
Modern Russia is also nowhere near the unstoppable conventional military juggernaut that the Cold War-era USSR was.
[1] https://en.wikipedia.org/wiki/List_of_conflicts_in_South_Ame...
What of missiles coated the same way?