LGM-35A Sentinel - Ground-Based Strategic Deterrent (GBSD) program

The proper way for a US road-mobile system would be to go with a shell game. Say 200 road-mobile systems with 10 harden hangars for each. You randomly rotate vehicles and decoys between shelters and now the enemy needs to hit 2,000 targets instead of 200. It would be expensive though, since you need 2,000 sites and have them all manned.
 
I kinda doubt that US armed guard would heistate to shoot any unauthorised person approaching the ICBM silo. America have quite a lot of unused land, that could be safely federalized for ICBM dispersion.
Ask the nun who was sentenced to several years for sneaking through the fence at a nuclear weapons production facility.

Or the teenagers who got very lost and went to the nearest farmhouse to get directions.

Despite orders allowing the use of force, no US soldier wants to use deadly force on civilians. Mostly because as soon as we did we'd be going to our own court-martial. I was qualified Reaction Force for the subs. Armed watches, too. If we fired, even if we were objectively justified, we were still going on trial. Even if the immediate investigation stated that the shoot was justified.
 
I feel the sun has set on land mobile basing. The PRC has some -400 remote sensing satellites, with two hundred of those launched just in 2022 and 2023. Any hope of hiding massive 5-6 axle TELs and their support and security infrastructure will be gone soon. The Russians already escort their TELs with dazzler lasers for this reason. In the U.S. one would also have to contend with commercial UAVs operated by foreign agents. There is no longer much advantage to land based mobile missiles.
The GMTI-capable satellites will certainly pose some problem for mobile TELs. I guess if they're on the move at the time of launch, then they could still probably escape, without some kind of mid-course update and terminal homing capability on the missile/warheads that is.
 
I don’t read that as additional silos but refurbishment of existing operational MMIII silos
The Sentinel, which will modernize 400 missiles, 450 silos and more than 600 facilities across almost 40,000 square miles of U.S. territory over 6 states, 3 operational wings and a test location, is scheduled to replace the LGM-30G Minuteman III intercontinental ballistic missile weapon system.

Maybe the '1' should have been a '4'. 150 could just be due to a journalist's crappy handwriting. This is more definitive:

The Air Force plans to acquire 642 missiles to support testing and the deployment of a force of 400 missiles. The Air Force expects the program to reach its initial operational capacity, with nine missiles on alert, by 2029; it expects to complete the deployment in 2036. The Sentinel program encompasses both the missile itself and its associated infrastructure, including launch and flight-related capabilities. The FY2023 NDAA authorized funding the program at request and would prohibit any reduction in alert levels or reduction of the quantity of deployed ICBMs below 400 total.
 
The GMTI-capable satellites will certainly pose some problem for mobile TELs. I guess if they're on the move at the time of launch, then they could still probably escape, without some kind of mid-course update and terminal homing capability on the missile/warheads that is.
which leads to the question: Pershings had MARVs. Are those MARVs still available somewhere, and could we stick those onto a Minuteman/Trident/Sentinel?
 
which leads to the question: Pershings had MARVs. Are those MARVs still available somewhere, and could we stick those onto a Minuteman/Trident/Sentinel?
A Pershing II MaRV would be way too big to carry any more than one of. However, it was built with late-70s tech, so you could potentially build smaller versions today. It would of course need to work at higher speeds though. There was also something called AMARV and PGRV.
EDIT: Found the link at last:
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Of course if GAM-87 Skybolts had made it into service, then Pershing MaRV tech would likely have made it onto those and, as an ALBM, would have continued development unaffected by the INF Treaty. And we wouldn't have to develop/cancel HCSW because it would already exist and LRHW would just be a ground-launched version, with very little development work required... sigh.
 
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The proper way for a US road-mobile system would be to go with a shell game. Say 200 road-mobile systems with 10 harden hangars for each. You randomly rotate vehicles and decoys between shelters and now the enemy needs to hit 2,000 targets instead of 200. It would be expensive though, since you need 2,000 sites and have them all manned.

Now adays you would also need anti UAV defenses at all of the sites. Also i am not convinced a shell game is even workable anymore with the shear number of remote sensing satellites being put in orbit. Within a decade the U.S. and China will probably have revisit times measured in hours or minutes and GMTI capability. One could deploy jammers and lasers and harden the shelters to take near misses and such, but at some point it seems to me the simplicity of silos and security of submarines is just a better dynamic.
 
which leads to the question: Pershings had MARVs. Are those MARVs still available somewhere, and could we stick those onto a Minuteman/Trident/Sentinel?

I’m sure those are long gone. The modern solution would probably be some kind of biconical hypersonic glider. Pershing had rather large control surfaces that would be difficult to package.

Although I question if any kind of MARV is necessary. Is either Russia or China on the road to a meaningful ABM defense?
 
which leads to the question: Pershings had MARVs. Are those MARVs still available somewhere, and could we stick those onto a Minuteman/Trident/Sentinel?
Those MARVs were not designed for ICBM ranges, we do have CPS these days, but also not for ICBM ranges. Switching an RV for a MARV adds weight and reduces payload, so unless there is a specific need, plain RVs are better.
 
Now adays you would also need anti UAV defenses at all of the sites. Also i am not convinced a shell game is even workable anymore with the shear number of remote sensing satellites being put in orbit. Within a decade the U.S. and China will probably have revisit times measured in hours or minutes and GMTI capability. One could deploy jammers and lasers and harden the shelters to take near misses and such, but at some point it seems to me the simplicity of silos and security of submarines is just a better dynamic.
Shell game would require harden shelters, so you still need nukes to take each of them out, and enough decoys to put in each shelter (semi trucks should be cheap enough). Satellites would not be an issue since a truck is a truck and satellites can't peek inside trucks.

But yes it would be more expensive and slightly less secure than silos. But it would be easy to complicate enemy targeting by simply building more shelters.
 
They are designed for a different kind of scenario. You can fit a Midgetman into a tractor-trailer, which would greatly simplify decoys.
 
They are designed for a different kind of scenario. You can fit a Midgetman into a tractor-trailer, which would greatly simplify decoys.

It seems unlikely any TEL would mimic a standard trailer and if it did, it would certainly be limited to actual paved roads.
 
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They are designed for a different kind of scenario. You can fit a Midgetman into a tractor-trailer, which would greatly simplify decoys.
Even a small ICBM is well above the regular weight limits for a traditional tractor trailer. You'd need something with more axles, basically a mobile crane truck. And then you need the security package to travel with them.

Remember, the orbital resolution limit is about 5cm/2"
 
Those MARVs were not designed for ICBM ranges, we do have CPS these days, but also not for ICBM ranges. Switching an RV for a MARV adds weight and reduces payload, so unless there is a specific need, plain RVs are better.
My thinking was MARVs for "Scud Hunting" of mobile launchers.

TELs can displace a good distance in the flight time of an ICBM.
 
If you are using a shell-game you can stick to paved roads, and fixed known sites which can have defensive measures and security built in, like current silos. Security teams would only be needed when moving from shelter to shelter.

Your view of orbital satellites is... optimistic.

Too much risk in using an ICBM RV that requires mid-course updates. SCUD hunting will be done by B-21s and F-35s.
 
If you are using a shell-game you can stick to paved roads, and fixed known sites which can have defensive measures and security built in, like current silos. Security teams would only be needed when moving from shelter to shelter.
You still need them generally available. And need to use them EVERY TIME you move a missile or decoy. Which greatly increases the cost of road-mobile ICBMs.

Plus, the fixed sites need nearly as much hardening as silos.

Note that the Russian, Chinese, and North Korean TELs are all off-pavement capable things. The US has a lot of land in the west and midwest that could be used for dispersal sites, but the same idea was looked at for MX and Midgetman and then discarded because of how little land they had available, relative to the number of nukes it'd take to saturate the area.


Your view of orbital satellites is... optimistic.

Too much risk in using an ICBM RV that requires mid-course updates. SCUD hunting will be done by B-21s and F-35s.
If you think a satellite isn't capable of IDing a TEL from a semi truck, I don't know what to say.

Yes, Scud hunting was one of the roles for B-2 and likely B-21. I doubt F-35s have the range and loiter to be very effective at hunting mobile ICBMs, but TBM/IRBMs I'll agree with.

Having some MARVs available to hunt down mobile ICBMs that are outside the area a B21 can get to in time is simply good planning.
 
Your view of orbital satellites is... optimistic.
Too much risk in using an ICBM RV that requires mid-course updates. SCUD hunting will be done by B-21s and F-35s.
Mobile ICBMs would be long gone by the time they get there.
 
You still need them generally available. And need to use them EVERY TIME you move a missile or decoy. Which greatly increases the cost of road-mobile ICBMs.

Plus, the fixed sites need nearly as much hardening as silos.
The 'shell game' thing also requires that all of your dispersed shelters have identical command & control systems, which is one of the big cost drivers in the system. Your decoys need to be the same shape, size, and mass distribution as the live rounds.

It doesn't take a lot before the cost savings for the shell game work out minimal compared to just having more live rounds.
 
The 'shell game' thing also requires that all of your dispersed shelters have identical command & control systems, which is one of the big cost drivers in the system. Your decoys need to be the same shape, size, and mass distribution as the live rounds.

It doesn't take a lot before the cost savings for the shell game work out minimal compared to just having more live rounds.
Yep. Making sufficiently-convincing decoys is eye-wateringly expensive...

If your decoys start costing more than about 50% of the live missile, you might as well just use live missiles and fewer sites than the full decoy spread. And since we're probably closer to 90% of the cost of a missile here, definitely just go with more missiles.
 
Your view of orbital satellites is... optimistic.

The NRO just launched 21 satellites, one of six launches this year. If they are deploying their satellites in tranches like the SDA PWSA, then they likely have 300-400 recon birds in orbit inside the next several years. The PRC likely continues to orbit a hundred more satellites every year as well, and I suspect that pace increases dramatically as soon as they make the upcoming Long March 10 reusable (or possibly the new LandSpace platform). The PRC has also launched EO satellites into GEO, where they can dwell on any target within their line of site. Currently thsee are only in the Pacific, but that could easily change.

Any missile deployment going forward is going to have to deal with an extremely capable and persistent ISR capability. Truck basing strikes me as a hopeless dead end at this point.
 
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The NRO just launched 21 satellites, one of six launches this year. If they are deploying their satellites in tranches like the SDA PWSA, then they likely have 300-400 recon birds in orbit inside the next several years.
no, they won't be photo reconnsats. And the other launches aren't clusters
 
I never stated they would be. In any case, in seems likely the PRC controls a thousand remote sensing satellites by end of decade. It seems like the absolutely wrong time to get into ground mobile deployments.

I wish more people would accept this reality.
 
The 'shell game' thing also requires that all of your dispersed shelters have identical command & control systems, which is one of the big cost drivers in the system. Your decoys need to be the same shape, size, and mass distribution as the live rounds.

It doesn't take a lot before the cost savings for the shell game work out minimal compared to just having more live rounds.
The cost is most certainly an issue and why the US has stuck to silos.

The cost of decoys can be significantly reduced by making the TEL externally look exactly like a tractor-trailer, the whole idea depends on being able to place something like a Midgetman inside a tractor-trailer. Yes a satellite can tell a TEL from a semi, but it can't look inside a semi's box nor tell semi's apart.
 
The cost is most certainly an issue and why the US has stuck to silos.

The cost of decoys can be significantly reduced by making the TEL externally look exactly like a tractor-trailer, the whole idea depends on being able to place something like a Midgetman inside a tractor-trailer. Yes a satellite can tell a TEL from a semi, but it can't look inside a semi's box nor tell semi's apart.

The idea would also hinge on developing a new Migetman…
 
The cost of decoys can be significantly reduced by making the TEL externally look exactly like a tractor-trailer, the whole idea depends on being able to place something like a Midgetman inside a tractor-trailer. Yes a satellite can tell a TEL from a semi, but it can't look inside a semi's box nor tell semi's apart.

The ultimate extension of shell-game would be a vehicle that was both generally invisible to orbital sensors and also had an infinite number of possible firing locations. A submarine, for example...

GBSD is on very shaky ground doctrinally and strategically.
 
The idea would also hinge on developing a new Migetman…
I think the current thinking hinges on a mobile launcher for the LGM-35A, another new missile seems unlikely given funding. But given the ever growing limitations on the advantage offered by land mobile ICBMs, an MICBM seems unlikely either way. The efficient method of achieving the same difference is putting more warheads on SLBMs.

The ultimate extension of shell-game would be a vehicle that was both generally invisible to orbital sensors and also had an infinite number of possible firing locations. A submarine, for example...

GBSD is on very shaky ground doctrinally and strategically.
The first part I agree with, the second I don't. This makes it clear:

The Air Force plans to acquire 642 missiles to support testing and the deployment of a force of 400 missiles. The Air Force expects the program to reach its initial operational capacity, with nine missiles on alert, by 2029; it expects to complete the deployment in 2036. The Sentinel program encompasses both the missile itself and its associated infrastructure, including launch and flight-related capabilities. The FY2023 NDAA authorized funding the program at request and would prohibit any reduction in alert levels or reduction of the quantity of deployed ICBMs below 400 total.

The whole point of a Triad is safety through redundancy. What happens if say there's a setback/problem with the Columbia Class subs, or a design flaw that allows them to be tracked? If you have ICBMs, you have a fallback plan, if you don't you have no paddle. At the moment the Triad is very SLBM heavy, which could be either good or bad, depending on the exact scenario.
 
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The whole point of a Triad is safety through redundancy. What happens if say there's a setback/problem with the Columbia Class subs, or a design flaw that allows them to be tracked? If you have ICBMs, you have a fallback plan, if you don't you have no paddle. At the moment the Triad is very SLBM heavy, which could be either good or bad, depending on the exact scenario.
Each leg of the triad does different tasks, it's not only about having to destroy 3x the amount of targets as just land based missiles or just bombers.

  • Bombers are the obvious "we are raising alert levels" tool. They let you signal to other countries the relative irritation level the US has. People see them take off, other countries see the bombers on radar.
  • Silo based missiles are a use or lose tool. They were the most accurate missiles for a long time because the missiles knew exactly where they were starting from. This meant that silo missiles were counter-force, able to specifically target silos or command and control points. But because both sides knew exactly where the missiles were, they were also a primary target of the other side's silo missiles. If you get a launch indication, you have however long that missile's flight time is to verify that it is a real launch and then tell your missiles to stand down. Because they went to launch alert as soon as the indication was detected and would launch a minute or two before the incoming missiles would land. Use or Lose.
  • Submarines are the "even if you destroy my country, we will still destroy you in retaliation" tool. The true holders of MAD. Up until Trident (and really Trident II), SLBMs were not accurate enough for hitting individual silos or C&C points, so there was no point in using them as a first strike. Now, Trident makes it possible, but then you don't have any retaliation capabilities.
How accurate were SLBMs? Well, what we always told tourists on the boats was to picture the Kingdome or your local Major League baseball field. First generation missiles would land somewhere in the parking lot of the stadium. Second generation missiles would land somewhere inside the stadium, probably up in the bleachers somewhere. Third generation missiles were a lot more accurate, they'd land somewhere inside the infield. And fourth generation missiles could call which corner of the pitcher's rubber they'd land on.

One of the STRATCOM heads has said that he's seen Tridents land where the target point was inside the impact crater. And remember that this is a completely unarmed RV, so this is a kinetic crater from some 200kg landing at ~1000m/s (because RVs really slow down in the last 20,000ft). KE = 0.5 * M * V^2, so 200 megajoules of thump.
 
Each leg of the triad does different tasks, it's not only about having to destroy 3x the amount of targets as just land based missiles or just bombers.

  • Bombers are the obvious "we are raising alert levels" tool. They let you signal to other countries the relative irritation level the US has. People see them take off, other countries see the bombers on radar.
  • Silo based missiles are a use or lose tool. They were the most accurate missiles for a long time because the missiles knew exactly where they were starting from. This meant that silo missiles were counter-force, able to specifically target silos or command and control points. But because both sides knew exactly where the missiles were, they were also a primary target of the other side's silo missiles. If you get a launch indication, you have however long that missile's flight time is to verify that it is a real launch and then tell your missiles to stand down. Because they went to launch alert as soon as the indication was detected and would launch a minute or two before the incoming missiles would land. Use or Lose.
  • Submarines are the "even if you destroy my country, we will still destroy you in retaliation" tool. The true holders of MAD. Up until Trident (and really Trident II), SLBMs were not accurate enough for hitting individual silos or C&C points, so there was no point in using them as a first strike. Now, Trident makes it possible, but then you don't have any retaliation capabilities.
How accurate were SLBMs? Well, what we always told tourists on the boats was to picture the Kingdome or your local Major League baseball field. First generation missiles would land somewhere in the parking lot of the stadium. Second generation missiles would land somewhere inside the stadium, probably up in the bleachers somewhere. Third generation missiles were a lot more accurate, they'd land somewhere inside the infield. And fourth generation missiles could call which corner of the pitcher's rubber they'd land on.

One of the STRATCOM heads has said that he's seen Tridents land where the target point was inside the impact crater. And remember that this is a completely unarmed RV, so this is a kinetic crater from some 200kg landing at ~1000m/s (because RVs really slow down in the last 20,000ft). KE = 0.5 * M * V^2, so 200 megajoules of thump.
That kind of accuracy surprises me, I was under the impression, CEP was around 100m for D5s, although I read in the early '90s that PGRV (basically an AMARV with terminal homing) would be accurate to a CEP of 20m.
 
One of the STRATCOM heads has said that he's seen Tridents land where the target point was inside the impact crater. And remember that this is a completely unarmed RV, so this is a kinetic crater from some 200kg landing at ~1000m/s (because RVs really slow down in the last 20,000ft). KE = 0.5 * M * V^2, so 200 megajoules of thump.
Frankly, this sounds more like a bragging for civilians.
 
They were the most accurate missiles for a long time because the missiles knew exactly where they were starting from.
I would venture to suggest that this is still the case, for the same reason. But when you're throwing thermonuclear warheads around, the difference in accuracy with modern weapons is insignificant.
The cost of decoys can be significantly reduced by making the TEL externally look exactly like a tractor-trailer, the whole idea depends on being able to place something like a Midgetman inside a tractor-trailer. Yes a satellite can tell a TEL from a semi, but it can't look inside a semi's box nor tell semi's apart.
Sure, but it needs to be a tractor-trailer that has all the same external signatures as a live TEL to anything you think the bad guys might get within detection distance. That doesn't just mean the same outer mould line, but:
  • Mass and mass distribution. When it goes over a bridge, the bridge needs to deflect identically.
  • Thermal signature. A live weapon will, at a minimum, emit some level of decay heat. Are the hot spots in the same places and equally hot?
  • Radiation signature. A live weapon will emit some level of radiation. Your decoy needs to be able to mimic that. You can shield it to some extent, but then you're increasing your mass and thermal signatures.
  • Chemical signature. If anything in your weapon offgasses, then that's detectable.
  • Technical signature: If you've got 1 live launcher and 4 decoys, and only one launcher is fitted with a missile turboencabulator, then intelligence sources can just pull the maintenance records for the turboencabulators. If the decoys have signature emulators, then the ones that don't are clearly live.
  • Operational signature: obvious, but not trivial. Your decoys need to be moved like they're live. Full security detail. Full security clearance for everyone who touches them. That's a huge cost.
And that's just the ones I've though of while on a tea break.

Sure, some of these may not be easily observed by satellite. But if you're planning to disperse by road, any competent bad guy is going to have some special operations or intelligence types a mile or two from key choke points with a good telescope and sensing devices.

The technical and operational stuff basically implies that your decoy and live TELs are absolutely identical. Most just have a missile simulator in them, and the rest have a live missile. As few people as possible - and ideally nobody in the missile convoy - knows which are live.

The question then becomes, how much more expensive is it to have more live missiles? If the missile is a low proportion of the overall system cost - either because the missile is cheap or you need a lot of decoys - then it may turn out that decoys don't save money.
 
Has the US ever explored mimicking China with their mountainous tunnel networks, where their TELs can pop out of any of the numerous entrances to stage an attack?

Not only can a complex like that provide cover, but concealment of movement, maintenance, and preparation too. And it would be re-usable infrastructure for future missiles.
 
I would venture to suggest that this is still the case, for the same reason. But when you're throwing thermonuclear warheads around, the difference in accuracy with modern weapons is insignificant.

Sure, but it needs to be a tractor-trailer that has all the same external signatures as a live TEL to anything you think the bad guys might get within detection distance. That doesn't just mean the same outer mould line, but:
  • Mass and mass distribution. When it goes over a bridge, the bridge needs to deflect identically.
  • Thermal signature. A live weapon will, at a minimum, emit some level of decay heat. Are the hot spots in the same places and equally hot?
  • Radiation signature. A live weapon will emit some level of radiation. Your decoy needs to be able to mimic that. You can shield it to some extent, but then you're increasing your mass and thermal signatures.
  • Chemical signature. If anything in your weapon offgasses, then that's detectable.
  • Technical signature: If you've got 1 live launcher and 4 decoys, and only one launcher is fitted with a missile turboencabulator, then intelligence sources can just pull the maintenance records for the turboencabulators. If the decoys have signature emulators, then the ones that don't are clearly live.
  • Operational signature: obvious, but not trivial. Your decoys need to be moved like they're live. Full security detail. Full security clearance for everyone who touches them. That's a huge cost.
And that's just the ones I've though of while on a tea break.

Sure, some of these may not be easily observed by satellite. But if you're planning to disperse by road, any competent bad guy is going to have some special operations or intelligence types a mile or two from key choke points with a good telescope and sensing devices.

The technical and operational stuff basically implies that your decoy and live TELs are absolutely identical. Most just have a missile simulator in them, and the rest have a live missile. As few people as possible - and ideally nobody in the missile convoy - knows which are live.

The question then becomes, how much more expensive is it to have more live missiles? If the missile is a low proportion of the overall system cost - either because the missile is cheap or you need a lot of decoys - then it may turn out that decoys don't save money.
Accuracy is a huge deal when hitting hardened targets and it allows you to use smaller warheads.

I've seen radiation detectors in use, its not quite that easy. Also we are talking about shifting trucks from one shelter to another a couple miles away, on remote easily secured roads. Yes the decoys would also need security when moving, but you only need to shift 2-3 trucks at any one time per a group of say 10 (1 warhead, 9 decoys), so you only need 2-3 security teams.

And yes building more missiles is al;ways an option, but if you can't build more missiles due to say treaties or politics, that's when then shell game starts paying off, since for example you can go from 400 targets to 4,000 targets while staying under New START limits.
 
Has the US ever explored mimicking China with their mountainous tunnel networks, where their TELs can pop out of any of the numerous entrances to stage an attack?

Not only can a complex like that provide cover, but concealment of movement, maintenance, and preparation too. And it would be re-usable infrastructure for future missiles.
The WS120-A was considered for “deep mountain basing” with multiple launch points through connected tunnels. I think it was also included in the massive STRAT-X study much of which is still classified.

But long story short cost, as already mentioned, was a huge factor.
 

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