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Long Range Precision Fires

bring_it_on

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Yes there are many options available across the spectrum. LRHW seems to be on track, but 2021 tests will likely be indicative of whether that first battery will be fielded by 2023 or not. Anyhow, an option exists to scale that program up so you aren't really focusing on invention as much as acquisition and production. PrSM likewise should be doable by 2023 if not maybe by 2024 with 2021 testing again likely to be indicative of whether they stick to their timelines or not. Adapting navy's missiles likewise is a pretty low risk path to get that medium range fires capability and OpFires remains that high end higher risk capability which is going to be hugely dependent upon what DARPA is able to demonstrate. It is really impressive what they are attempting to do and it would be foolish for the Army to back out of that program and leave DARPA without a transition partner.

I think the Army is in a relatively good place with its LRPF effort. The limiting factor is going to be acquisition funding and that will likely determine the high:low and Short, medium and long range mix in the inventory. SLRC and some of the far term capabilities are probably less certain but those are essentially S&T programs so not really part of any inventory discussion at the moment as far as I can tell.
 

marauder2048

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And terminally, that missile is coming in close to the max elevation angle for the radar
Might be a concern only if firing at single AA battery standing in the middle of the desert. Not against proper ADN.
I want to know more about the proper ADNs that just happen to be scanning the column
above another engagement radar with sufficient reaction time to launch an interceptor
with a short enough flyout and good enough kinematics to hit a high diver.
 

marauder2048

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Deep throttling upgrades with thrust vectoring could get you a controllable SRM within a missile with lesser drag from control surfaces
The plan very much is to field a family of LRPF (Army budgets permitting) across a spectrum of performance, range and cost. PrSM is just the lower end/entry level of that capability. LRHW is actually pacing if not exceeding the pace of PrSM. But PrSM itself is open to some enhancement over its life cycle with both a seeker and possibly a propulsion upgrade possible inside a decade or so. For how much the Army is expecting to pay for the AUR, it actually brings some pretty good capability IMHO.
Agreed; I tend to think they'd look at the throttleable boosters developed for OpFires.
 

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Any good AD system should have overlap and point defenses, but that said the combination of high velocity, high altitude, and rapid bearing changes probably makes a SAM battery its own best line of defense unless an AD battalion is closely packed or employs data feeds from off site radars.

This is a problem for all sides trying to counter such an attack. CENTCOMs Al Uldeid has a pair of visible MIM-104 batteries and Kadena AFB has an entire battalion assigned to it.
 

marauder2048

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Any good AD system should have overlap and point defenses, but that said the combination of high velocity, high altitude, and rapid bearing changes probably makes a SAM battery its own best line of defense unless an AD battalion is closely packed or employs data feeds from off site radars.
AFAIK, the number of crossing high-diver intercepts is zero.

The high-diver intercepts to date have been mainly the province of big naval radars and even SM-6 requires an illuminator.
And those were operating against targets with much lower altitude corridors.
 

marauder2048

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No matter what you do with the inlets, a ramjet reduces the diameter and thus weight of the payload.
Is that true for annular warheads? They already have a raceway through the interior that if you look at the typical
air capture area/projectile diameter ratios for SFRJs seems to be just fine.

They do seem to be heavier than standard solid warheads.

mk125-warhead.png
 

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Josh_TN

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Any good AD system should have overlap and point defenses, but that said the combination of high velocity, high altitude, and rapid bearing changes probably makes a SAM battery its own best line of defense unless an AD battalion is closely packed or employs data feeds from off site radars.
AFAIK, the number of crossing high-diver intercepts is zero.

The high-diver intercepts to date have been mainly the province of big naval radars and even SM-6 requires an illuminator.
And those were operating against targets with much lower altitude corridors.
Its a tough nut to crack. But it is a problem for all AD. I don't know enough to say who can actually defend against that, if at all. I suspect no one posting does. But it is a heavy lift, and not unique to one specific side.

Actually what I'm a little afraid of is that a first strike with conventional weapons is rapidly approaching the level of being so effective that it is too close to nuclear: If China decided to bombard every single US base in the WestPAC, what would be left?

On the other side, if two B-2s suddenly showed up over Dalian, they could drop double tap 80 targets in 30 seconds. And any SSGN with 150 missiles is basically a Pearl Harbor moment waiting to happen. Conventional PGMs are so destructive, they can break a top tier player in a couple hours.

I think one of the problems of arms control or stability in general is that it now only takes a few platforms to completely change a theater. I think that is massively destabilizing, but I've no idea how to change that dynamic. It is a game that favors the first strike; and hypersonics are just going to make that logic worse.


Because defense is so hopeless, the only alternative is massive conventional response. But without the fear that nukes put out.
 

TomS

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No matter what you do with the inlets, a ramjet reduces the diameter and thus weight of the payload.
Is that true for annular warheads? They already have a raceway through the interior that if you look at the typical
air capture area/projectile diameter ratios for SFRJs seems to be just fine.

They do seem to be heavier than standard solid warheads.

View attachment 646919

At least sometimes, that channel in the middle of the warhead is full of other stuff.
 

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GARGEAN

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I want to know more about the proper ADNs that just happen to be scanning the column
above another engagement radar with sufficient reaction time to launch an interceptor
with a short enough flyout and good enough kinematics to hit a high diver.
Just as one example - 30N6 in variations can reach up to 85 degrees elevation. If, as mentioned above, won't be standing alone in the field - things are getting even more interesting with stuff from 64N6 to Nebo-M providing early warning and queing... And that's mostly for S-300P. Then there is things like S-400 with 91N6 with bit more modest elevation of 75 degrees but much handier scanning sectors. And then there is S-300V4 which is specifically made to work against TBMs and sometimes even more juicy ballistic/quaziballistic targets.

So as usual: all that speed, altitude and angles are definitely useful. But they don't make it immune against proper ADN. As well as proper ADN is not immune against such targets, especially used en masse.
 

marauder2048

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No matter what you do with the inlets, a ramjet reduces the diameter and thus weight of the payload.
Is that true for annular warheads? They already have a raceway through the interior that if you look at the typical
air capture area/projectile diameter ratios for SFRJs seems to be just fine.

They do seem to be heavier than standard solid warheads.

View attachment 646919

At least sometimes, that channel in the middle of the warhead is full of other stuff.
For a 5 inch diameter missile sure.
 

marauder2048

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I want to know more about the proper ADNs that just happen to be scanning the column
above another engagement radar with sufficient reaction time to launch an interceptor
with a short enough flyout and good enough kinematics to hit a high diver.
Just as one example - 30N6 in variations can reach up to 85 degrees elevation. If, as mentioned above, won't be standing alone in the field - things are getting even more interesting with stuff from 64N6 to Nebo-M providing early warning and queing... And that's mostly for S-300P. Then there is things like S-400 with 91N6 with bit more modest elevation of 75 degrees but much handier scanning sectors. And then there is S-300V4 which is specifically made to work against TBMs and sometimes even more juicy ballistic/quaziballistic targets.

So as usual: all that speed, altitude and angles are definitely useful. But they don't make it immune against proper ADN. As well as proper ADN is not immune against such targets, especially used en masse.
It's the scan losses at the high elevation angles that make the high diver intercept geometry tricky along with
the aspect angle of the high diver relative to most interceptors and the radar i.e. it's a head-on intercept.

And the apogee of a 499+ km SRBM on MET is going to be 100 - 125 km which will overfly just about anything
on the S-400 side; so it's going to be an intercept attempt after pull-down if any.

The fundamental issue facing proper ground based ADNs is that they are expensive and low density
and the improving ground based fires opposite them are comparatively cheap and numerous.
 

GARGEAN

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It's the scan losses at the high elevation angles that make the high diver intercept geometry tricky along with
the aspect angle of the high diver relative to most interceptors and the radar i.e. it's a head-on intercept.

And the apogee of a 499+ km SRBM on MET is going to be 100 - 125 km which will overfly just about anything
on the S-400 side; so it's going to be an intercept attempt after pull-down if any.

The fundamental issue facing proper ground based ADNs is that they are expensive and low density
and the improving ground based fires opposite them are comparatively cheap and numerous.
Losses are there, but not as huge as one might think, esp considering most of those radars have mechanical steering and different modes with some specifically made to work against ABMs. Head-on often makes things in fact less tricky since negates parameter losses and loads for missiles and leaves only fuzing problem, which is hardly a problem giving target speed limits from 2800m/s to 4800m/s for different missiles.


As for heigh limit - it's a question to be poked, since from what I see PrSM is quiaziballistic but by far not to the extent of Iskander, mainly due to substantially more limited size. So apogee itself is a bit of a lesser concern, unless we are looking at midcourse intercept which is quite a different can of worms from terminal. But even then there are things like 77N6/9M82MV to not be forgotten.

As for last part - definitely agree. In those situations attacker always have MASSIVE advantage. But initial question was about possibility of interception per se. And that possibility is there and not to be sneezed at.
 

marauder2048

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Losses are there, but not as huge as one might think, esp considering most of those radars have mechanical steering and different modes with some specifically made to work against ABMs.
AFAIK, none of these radars can adjust elevation on the fly in short enough order to make a meaningful difference in reducing scan angle losses.

The classic argument favoring head-on engagement is that the fuze timing/sensitivity is relaxed since the fuze/warhead fragments
are being swept over the greatest possible target area. But the guidance laws that achieve this typically assume that the seeker
and/or radar look angles are not substantially head-on for most of the engagement i.e. the look angles are not unfavorable.

Apogee tends to be indicative of the overall altitude corridor during midcourse; since terminal here is going to be a short,
near vertical pull-down that's the only real opportunity to intercept.
 

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AFAIK, none of these radars can adjust elevation on the fly in short enough order to make a meaningful difference in reducing scan angle losses.

The classic argument favoring head-on engagement is that the fuze timing/sensitivity is relaxed since the fuze/warhead fragments
are being swept over the greatest possible target area. But the guidance laws that achieve this typically assume that the seeker
and/or radar look angles are not substantially head-on for most of the engagement i.e. the look angles are not unfavorable.

Apogee tends to be indicative of the overall altitude corridor during midcourse; since terminal here is going to be a short,
near vertical pull-down that's the only real opportunity to intercept.

Why should it adjust in the last seconds? It has specialized ABM mods to be commonly used in BM-dangerous environmen. Or we assume it won't be used in any circumstances?

That terminal dive is nice indeed, but putting it as only opportunity to intercept is quite a huge stretch. It should mean that missile is at the very least slightly more energetic than Iskander, which, I must admit, I found quite a bit doubtful giving its size. It should either go at quite a bit lower alt or should have quite a bit more relaxed trajectory and not have 100km alt anywhere near terminal. Or maybe I don't know something revealed about missile (not trying to be a smartass, geniune question)

Plus, well, 77N6/9M82MV point stands even in case of PrSM trajectory being as square as one can only wish.
 

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Iskander is a much larger weapon with a much larger warhead. ATACMS is already less than half the total weight of Iskander and PrSM is presumably significantly lighter. That said, if you look at a PrSM cutaway, it is almost all propellant with a rather small warhead (tiny in comparison to Iskander). I could see it having a similar flight profile, although I'd still wager it flies a little lower and slower.
 

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Iskander is a much larger weapon with a much larger warhead. ATACMS is already less than half the total weight of Iskander and PrSM is presumably significantly lighter. That said, if you look at a PrSM cutaway, it is almost all propellant with a rather small warhead (tiny in comparison to Iskander). I could see it having a similar flight profile, although I'd still wager it flies a little lower and slower.
Well, speed I saw stated is around the same of Iskander, but thing is - in fact flying higher would be easier for a missile when compared with Iskander. Point of that one is it stays at around 50km by far most of the trajectory, sitting comfy way above any common AA but way below specialized ABM systems. So it is properly catchable only at the very end of flightpath. Plus maneuvers and such help quite a lot. But this requires an absolute shitload of energy being put not just into range, but into maintaining proper trajectory trough all that range. That's why missile is so massive.
 

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Why should it adjust in the last seconds? It has specialized ABM mods to be commonly used in BM-dangerous environmen. Or we assume it won't be used in any circumstances?
Even for a 30 degree tiltback angle that's still a 50% loss in effective aperture if the array is scanning to 90 degrees in elevation.
The combination of head-on aspect plus the frequency of the engagement radar makes that a very stressing shot.

Kinematically, PrSM's performance as shown in the video is straightforward; it's got ~ 3x the propellant volume of GMLRS-ER
while pushing the same payload. And the basic rule of thumb about apogee/range follows as well.
In the GMLRS-ER test, they hit apogee at 30 km for a 120km vertical dive shot.
 

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I think the Army has a path to getting a seeker on the PrSM (which is beginning flight testing soon) even though SCO's bets with ATACMS didn't pan out. Now if they were serious they would be investing in similar capability on a Op Fires like weapon system. Maybe DARPA is already thinking of something like that given the types of targets it has in mind.
 
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It never made sense to me to put that much effort into to ATACMS. Budgets are tight, the army has a HUGE portfolio of long range strike weapons to fund, and PrSM is the furthest along in that portfolio. Cutting up old missiles for new capability doesn't really make sense with this level of funding, and lets face it, if China makes a go/no go decision on a war, it isn't going to be because of the US Army.
 

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Title of that article is a tad misleading, Army terminated the program and then Congress zeroed out the budget in response. The contract Lockheed won to put SM-6 and Tomahawk on land superceded the ATACMS-based solution.
 

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As I understood it, those were two completely different requirements - ATACMS doesn't even have PrSM's 500 km range, and the Medium Range Capability that involves the USN missiles involves the range band outside PrSM. From what I read, ATACMS's upgrade was cancelled, because it is pointless as PrSM will be have a lot more range and speed anyway. I don't thing MCR was part of this decision in any way; it is in an entirely different range band between those weapons and LRHW (assuming that is purchased).
 

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It never made sense to me to put that much effort into to ATACMS. Budgets are tight, the army has a HUGE portfolio of long range strike weapons to fund, and PrSM is the furthest along in that portfolio. Cutting up old missiles for new capability doesn't really make sense with this level of funding, and lets face it, if China makes a go/no go decision on a war, it isn't going to be because of the US Army.
"That much"? Sticking a different seeker on an existing missile should be something we could do in our sleep. With one arm tied behind our backs.
 

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As I understood it, those were two completely different requirements - ATACMS doesn't even have PrSM's 500 km range, and the Medium Range Capability that involves the USN missiles involves the range band outside PrSM. From what I read, ATACMS's upgrade was cancelled, because it is pointless as PrSM will be have a lot more range and speed anyway. I don't thing MCR was part of this decision in any way; it is in an entirely different range band between those weapons and LRHW (assuming that is purchased).
And a relatively tiny warhead. Warhead size matters when going after something as large as a ship.
 

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It can be said that the PrSM will be like a Swiss army knife: a single tool with many accessories. Or like so many Batman gadgets in one Bat tool.
 

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As I understood it, those were two completely different requirements - ATACMS doesn't even have PrSM's 500 km range, and the Medium Range Capability that involves the USN missiles involves the range band outside PrSM. From what I read, ATACMS's upgrade was cancelled, because it is pointless as PrSM will be have a lot more range and speed anyway. I don't thing MCR was part of this decision in any way; it is in an entirely different range band between those weapons and LRHW (assuming that is purchased).
And a relatively tiny warhead. Warhead size matters when going after something as large as a ship.
I don't think the ATACMs has a lot of life left in it. I know the recently refurbed them for an extension, but the motors have to be hitting their sell by date soon. It just strikes me as a dead end to spend money on it.

PrSM probably will never sink a ship with that warhead, but I suspect it could mission kill a modern vessel easy enough. Especially if the seeker can pick the aim point like NSM/LRASM. Also at closer ranges I would think that PrSM would be coming down at a very vertical angle with a lot of speed.
 

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PrSM also gives them two shots at the target with the same launcher and I believe the seeker is aimed at not just ships but emitting ground targets as well. Thinking from the Army's perspective, I believe the prSM seeker is a different solution to what SCO was trying to integrate on ATACMS. It may be a better long-term strategy to go down that seeker. Additionally, PrSM is a newer weapon, about to enter production and one that is designed with an open architecture and room to grow. So the benefits that come from newer/future warheads, range extension etc will all ensure that the cross-domain variant also benefits from this. These benefits wouldn't have really come from ATACMS. Weren't they, at one point, considering mounting a JAGM seeker on the ATACMS? I just feel it would have created a bespoke variant of a weapon that the Army was going to transition away from making the program difficult to sustain and upgrade in the future.
 
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Slightly OT, but apparently the warhead for PrSM and the new HARM (AGM-88G?) use some kind of really fancy frag warhead. Anyone familiar with it?
 

marauder2048

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I don't think the ATACMs has a lot of life left in it. I know the recently refurbed them for an extension, but the motors have to be hitting their sell by date soon. It just strikes me as a dead end to spend money on it.
The SLEP involves regraining the motor and adding a proximity sensor.
CD ATACMS was just folding in the JAGM seeker into the last year of the SLEP.
And the total CD ATACMS inventory would have been small; 100 missiles.
 

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a existing Joint Intelligence Center (JIC) maybe which needs protection from nukes now. again as stated DMPIs and mobile DMPIs.. these folks are finally getting it.
 

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