F-15X: USAF Seems Interested

Too bad MOAB is too bulky. Maybe the US should consider investing in a new generation of thermobaric weapons, should do. good job messing up anything not in a HAS.

BLU-118 has a thermobaric explosive in a BLU-109 penetrator case. This would make for a few nice “big-ass holes” in the pavement that no one will be filling-in, in a hurry. A 4,500 lb version may be the business for a multipurpose F-35 airburst and deep penetration thermobaric weapon.

BLU-118/B Thermobaric Weapon

The BLU-118/B nomenclature was first reported on 21 December 2001, and this weapon is clearly unrelated to the BLU-118 500 lb. napalm canister used during the Vietnam war.

The BLU-118/B is a penetrating warhead filled with an advanced thermobaric explosive that, when detonated, generates higher sustained blast pressures in confined spaces such as tunnels and underground facilities. The BLU-118/B uses the same penetrator body as the standard BLU-109 weapon. The significant difference is the replacement of the high explosive fill with a new thermobaric explosive that provides increased lethality in confined spaces.

The BLU-118/B warhead uses a Fuze Munition Unit (FMU)-143J/B to initiate the explosive. The FMU-143 fuze has been modified with a new booster and a 120-millisecond delay. All weapon guidance systems and employment options currently used with the BLU-109 warhead are compatible with the new BLU-118/B warhead. …

… The BLU-118B was successfully tested at the Nevada Test Site on 14 December 2001. During that test, a Guided Bomb Unit (GBU)-24 laser-guided weapon using the BLU-118B warhead was dropped from an F-15E attack aircraft. The laser-guided bomb was "skipped" into a tunnel and exploded with a delayed fuze, which produced a significant growth in overpressure and temperature in the tunnel. When compared to the standard BLU-109 explosive, results showed the new thermobaric weapon generated a significant improvement in overpressure and pressure-impulse in the tunnel complex.
https://www.globalsecurity.org/military ... lu-118.htm

25 to 30% more impulse.

Responding to the need for improved capabilities to defeat enemies seeking refuge in tunnels in the early-days of Operation ENDURING FREEDOM, ARA helped deliver a 25%-30% improvement over the existing BLU-109 bomb. …
https://www.ara.com/projects/blu-118-bomb-development

… The BLU-118/B bomb body can be attached to a variety of laser guidance system packages, including the GBU-15, GBU-24, GBU-27, and GBU-28 laser guided bombs, as well as the AGM-130 missiles.

BLU-118B weapon operational concepts include vertical delivery with the bomb detonated at or just outside portal, skip bomb with short fuse (1st or second contact), skip bomb with long fuse (penetrate door, max distance down adit), and vertical delivery to penetrate overburden and detonate inside the tunnel adit.
https://www.ara.com/projects/blu-118-bomb-development

In the same way you could employ 7 equidistant pure fission bombs to replicate or exceed the shock destruction effects of a single 1 Mt device, 2xF-35 with 2x4,500 lb thermobaric weapons each, using MADL to coordinate precise targeting and timing of releases, could scale in the same way, to largely recreate the effects of a GBU-43/B Massive Ordnance Air Blast (minus the C-130 special-delivery).

If you want more bang add one more F-35 ... or two ... or three ... etc.

The MOAB drop in Afghanistan could potentially be replicated by just two stealthy F-35, with little or no warning indication.

https://youtu.be/-K1myT-mIt4

Wery nice for cleawing away weef top ... or air base buildings ... or any base for that matter ... or any tunnel/bunker complex.

BLU-109 and GBU-39 were designed for concrete strengths in the 5,000 - 10,000 psi range.

That's considered low-to-medium strength these days.

The High Speed Penetrating Weapon is designed for strengths up to 15,000 psi.

Beyond that, you need the bomber carried weapons or delivery by (medium-range or greater) ballistic missile.

BLU-109 and GBU-39 were designed for concrete strengths in the 5,000 - 10,000 psi range.

That's considered low-to-medium strength these days.

The High Speed Penetrating Weapon is designed for strengths up to 15,000 psi.

Beyond that, you need the bomber carried weapons or delivery by (medium-range or greater) ballistic missile.

"Back in the day" (80s) the USAF tested superhard silos of 50ksi. Saw a picture of one test where the end of the silo was sticking up out of the bottom of the crater, hardly scratched.

"Back in the day" (80s) the USAF tested superhard silos of 50ksi. Saw a picture of one test where the end of the silo was sticking up out of the bottom of the crater, hardly scratched.

Yeah. It's even somewhat analogous to the multiple protective shelter scheme for MX where
each shelter could also support a terminal defense system.

"Back in the day" (80s) the USAF tested superhard silos of 50ksi. Saw a picture of one test where the end of the silo was sticking up out of the bottom of the crater, hardly scratched.

Yeah. It's even somewhat analogous to the multiple protective shelter scheme for MX where
each shelter could also support a terminal defense system.

My favorite.

The High Speed Penetrating Weapon is designed for strengths up to 15,000 psi.

Besides cost of doing that, going through a hardened top can be replaced with punching through doors. Are doors going to stop JASSM? Or JSOW-C's broach warhead? Or even a BLU-109/JDAM-ER in a fast gliding mode of attack? Will they even stop an SDB doing the same thing? Anything long, thin, dense and fast is going to penetrate the doors easier (or even damage them so badly that they don't work).

You could even detonate a larger BLU-118 derivative inserted deep under the shelter, or under the pavement adjacent to the doors, with a new "big a$$ hole" where the door-opening was, that no longer opens.

So is an expensive extra hardened shelter the solution if an evolved weapon quickly defeats it? Or just a change in delivery mode of an existing one? If F-35s are dropping bombs on your airbase you already lost as nothing's going to be working too well, and the pavement is going to be a bunch of "big-ass holes".

The other option is to disperse but then space-based sensors and F-35 IR DAS, EOTS and SAR are going to locate those dispersal operating points fast unless the aim is to disperse them, hide them, and don't fly again.

Either way the OCA effort is still going to work.

Rods from God concept was the great way to deal with fortifications.

In that same article about USAF testing hardened silos they also recognized Soviet hardening could be substantially higher.

Besides cost of doing that, going through a hardened top can be replaced with punching through doors. Are doors going to stop JASSM? Or JSOW-C's broach warhead? Or even a BLU-109/JDAM-ER in a fast gliding mode of attack? Will they even stop an SDB doing the same thing? Anything long, thin, dense and fast is going to penetrate the doors easier (or even damage them so badly that they don't work).

The doors are typically protected by very large, very high and very thick berms.

Besides cost of doing that, going through a hardened top can be replaced with punching through doors. Are doors going to stop JASSM? Or JSOW-C's broach warhead? Or even a BLU-109/JDAM-ER in a fast gliding mode of attack? Will they even stop an SDB doing the same thing? Anything long, thin, dense and fast is going to penetrate the doors easier (or even damage them so badly that they don't work).

The doors are typically protected by very large, very high and very thick berms.

So insert a penetrator at 45 degrees and either blow a hole at the door or under the shelter. Even a glide weapon approach at 45 degrees with a broach warhead is going through the door, or wrecking them. Same for a BLU JDAM-ER.

Besides cost of doing that, going through a hardened top can be replaced with punching through doors. Are doors going to stop JASSM? Or JSOW-C's broach warhead? Or even a BLU-109/JDAM-ER in a fast gliding mode of attack? Will they even stop an SDB doing the same thing? Anything long, thin, dense and fast is going to penetrate the doors easier (or even damage them so badly that they don't work).

The doors are typically protected by very large, very high and very thick berms.

So insert a penetrator at 45 degrees and either blow a hole at the door or under the shelter. Even a glide weapon approach at 45 degrees with a broach warhead is going through the door, or wrecking them. Same for a BLU JDAM-ER.

There is a gap between the berm and the door but that's typically, by design, far too small for a
PGM to reliably traverse while missing the berm and hitting the door.

And of course it's a predictable trajectory that's vulnerable to the terminal defenses.

So insert a penetrator at 45 degrees and either blow a hole at the door or under the shelter. Even a glide weapon approach at 45 degrees with a broach warhead is going through the door, or wrecking them. Same for a BLU JDAM-ER.

There is a gap between the berm and the door but that's typically, by design, far too small for a
PGM to reliably traverse while missing the berm and hitting the door.

And of course it's a predictable trajectory that's vulnerable to the terminal defenses.

Oh come on, the 'gap' is not even close to small, you're exaggerating, strike fighters are not small aircraft. A JASSM can fly into a mine shaft, or even through a window, and it's specifically designed to defeat terminal defenses. JSOW-C does the same thing, just a bit slower. Both are very agile and precise. And we have just seen IDF defeat a modern GBAD (several times), and a JSM plus EA (MALD-J supporting) would do that much easier again. And many of the shelters will have different axis of attack directions.

A 4,500 lb version of a BLU-118, either through the top, or through a door, or inserted underneath the whole shebang, and lifting its floor, is going to wreck anything inside it. For some reason you seem resistant to admitting that affordable shelters aren't achievable against current and near future strike weapons.

At best you can place the aircraft underground, but again it's very expensive, but some countries do it, and that's why you'd want something like a multipurpose 4,500 lb thermobaric penetrator (with airburst option) on F-35s to hit with little or no warning. And there's no reason a LO version of a BLU can not be produced.

If the door is open (due to no warning) the bombs can go inside. If the doors are closed the jets can't fly anyway. Either way, you can still destroy the doors, or dig big-ass holes in front of them, as required, to make sure they can't get out and fly.

OCA attacks will work.

Oh come on, the 'gap' is not even close to small, you're exaggerating, strike fighters are not small aircraft. A JASSM can fly into a mine shaft, or even through a window, and it's specifically designed to defeat terminal defenses. JSOW-C does the same thing, just a bit slower. Both are very agile and precise.

JASSM and JSOW cave attack profiles require a fair amount of unobstructed approach.
Nothing like the trajectories needed here.

And these shelter systems are deliberately designed to permit one axis of attack against the doors
unless your PGM can do Death Star trench runs with 90 degree turns.

This is why the US is focused on penetrators but they are challenged by new materials and terminal
defenses. For the latter, think of something that operates from behind cover like a VL-launched
MHTK directed by a retractable KuRFS FCR.

For some reason you seem resistant to admitting that affordable shelters aren't achievable against current and near future strike weapons.

Because none of the current and near future strike weapons have much utility against current and near future
HAS defended by current and near future defenses.

OTOH, with no INF treaty, a combined F-35 and MRBM attack could be effective since the F-35s could
just focus on SEADing the ABM defenses (if any) that unmask to defend the base.

Oh come on, the 'gap' is not even close to small, you're exaggerating, strike fighters are not small aircraft. A JASSM can fly into a mine shaft, or even through a window, and it's specifically designed to defeat terminal defenses. JSOW-C does the same thing, just a bit slower. Both are very agile and precise.

JASSM and JSOW cave attack profiles require a fair amount of unobstructed approach.
Nothing like the trajectories needed here.

And these shelter systems are deliberately designed to permit one axis of attack against the doors
unless your PGM can do Death Star trench runs with 90 degree turns.

This is why the US is focused on penetrators but they are challenged by new materials and terminal
defenses. For the latter, think of something that operates from behind cover like a VL-launched
MHTK directed by a retractable KuRFS FCR.

For some reason you seem resistant to admitting that affordable shelters aren't achievable against current and near future strike weapons.

Because none of the current and near future strike weapons have much utility against current and near future
HAS defended by current and near future defenses.

OTOH, with no INF treaty, a combined F-35 and MRBM attack could be effective since the F-35s could
just focus on SEADing the ABM defenses (if any) that unmask to defend the base.

I can't take this seriously, you're greatly exaggerating the obstruction from berms and the relative difficulty of getting a clear angle of approach to doors and pavement. The JASSM image you provided even illustrates enough oblique angle with which to clear a berm and strike a door. That weapon can use any vertical angle of approach it needs. Berms are tens of meters back from doors, >30 meters is not unusual at all. Plus the angle of a berm will not exceed the angle of repose of the sediments used, and that is quite unlikely to exceed a slope of about 33 degrees, 25 degrees seems to be a typical angle. This offers effectively no significant obstruction to access via a powered or else gliding agile terminal weapon’s approach, to an impact directly on a door.

A 1,000 lb class broach warhead will breach with little difficulty. A penetrator like a BLU-118 is likely do the same. The doors will either be penetrated (likely), severely distorted, blown off, or at the least, rendered inoperable. If a penetrator weapon entered the sub pavement in front of the door, angling to go under the threshold before detonation the foundation will be undermined and the door likely blown off, plus it will create a massive hole where the pavement and soil was in front of the door opening. Unlikely anything in that shelter survives such an impact. I see no practical problem with attacking doors effectively with existing weapons, or of creating a specialized weapon with enough mass, speed and energy to smash through doors and impart a ruinous shock to the foundation and surrounding pavements.

I see no problem with creating a precision-guided 4,500 lb scaled-up version of a BLU-118 which will either penetrate through the top, penetrate the door by impact energy alone, or overpressure the door via a proximity airburst, or else insert itself under the foundation with explosion energy release around 25% of the shock energy of a MOP detonation, in relatively close proximity to the foundation, going predominantly upwards into a shelter cavity, and thoroughly undermining the foundation of the shelter, and blowing out the surrounding pavements.

Who’s building a shelter that can survive that? What shelter has doors that can deflect it? Who is building a berm closer than 30 m to such doors? And what berm has an angle of repose >35 degrees? And who has the funds to do this? The Saudi’s maybe.

And what’s so valuable that it needs this much money spent on a shelter that’s still very unlikely to survive a hit? Su35? H6K? J-10?

Not buying it.

It is a big plus for the attacker to have a narrow corridor for high explosives. Much more power can be garnered when the radius of the blast is confined. You get about 80% more effect in this circumstance. Aircraft shelters are much better at keeping mother nature out than bombs. Berms in front of doors may be good for near miss nukes, but they certainly are not the answer to modern guided weapons.

Oh come on, the 'gap' is not even close to small, you're exaggerating, strike fighters are not small aircraft. A JASSM can fly into a mine shaft, or even through a window, and it's specifically designed to defeat terminal defenses. JSOW-C does the same thing, just a bit slower. Both are very agile and precise.

JASSM and JSOW cave attack profiles require a fair amount of unobstructed approach.
Nothing like the trajectories needed here.

And these shelter systems are deliberately designed to permit one axis of attack against the doors
unless your PGM can do Death Star trench runs with 90 degree turns.

This is why the US is focused on penetrators but they are challenged by new materials and terminal
defenses. For the latter, think of something that operates from behind cover like a VL-launched
MHTK directed by a retractable KuRFS FCR.

For some reason you seem resistant to admitting that affordable shelters aren't achievable against current and near future strike weapons.

Because none of the current and near future strike weapons have much utility against current and near future
HAS defended by current and near future defenses.

OTOH, with no INF treaty, a combined F-35 and MRBM attack could be effective since the F-35s could
just focus on SEADing the ABM defenses (if any) that unmask to defend the base.

I can't take this seriously, you're greatly exaggerating the obstruction from berms and the relative difficulty of getting a clear angle of approach to doors and pavement. The JASSM image you provided even illustrates enough oblique angle with which to clear a berm and strike a door. That weapon can use any vertical angle of approach it needs. Berms are tens of meters back from doors, >30 meters is not unusual at all. Plus the angle of a berm will not exceed the angle of repose of the sediments used, and that is quite unlikely to exceed a slope of about 33 degrees, 25 degrees seems to be a typical angle. This offers effectively no significant obstruction to access via a powered or else gliding agile terminal weapon’s approach, to an impact directly on a door.

A 1,000 lb class broach warhead will breach with little difficulty. A penetrator like a BLU-118 is likely do the same. The doors will either be penetrated (likely), severely distorted, blown off, or at the least, rendered inoperable. If a penetrator weapon entered the sub pavement in front of the door, angling to go under the threshold before detonation the foundation will be undermined and the door likely blown off, plus it will create a massive hole where the pavement and soil was in front of the door opening. Unlikely anything in that shelter survives such an impact. I see no practical problem with attacking doors effectively with existing weapons, or of creating a specialized weapon with enough mass, speed and energy to smash through doors and impart a ruinous shock to the foundation and surrounding pavements.

I see no problem with creating a precision-guided 4,500 lb scaled-up version of a BLU-118 which will either penetrate through the top, penetrate the door by impact energy alone, or overpressure the door via a proximity airburst, or else insert itself under the foundation with explosion energy release around 25% of the shock energy of a MOP detonation, in relatively close proximity to the foundation, going predominantly upwards into a shelter cavity, and thoroughly undermining the foundation of the shelter, and blowing out the surrounding pavements.

Who’s building a shelter that can survive that? What shelter has doors that can deflect it? Who is building a berm closer than 30 m to such doors? And what berm has an angle of repose >35 degrees? And who has the funds to do this? The Saudi’s maybe.

And what’s so valuable that it needs this much money spent on a shelter that’s still very unlikely to survive a hit? Su35? H6K? J-10?

Not buying it.

Crushed stone offers a far higher angle of repose than sediment alone. I'm looking at a surge stockpile of ~4" minus rock with an angle of repose of about 45 degrees right now.