USAF / Applied Research Associates, Inc. (ARA) Next Generation Penetrator (NGP)

The British Grand Slam bomb had the capacity to drill fifty meters of rock, the main difference with the GBU-57 is in the guidance system and the sophisticated detonator, but the basic design is the same. Kinetic energy of free fall from high altitude. It would be reasonable to wonder why the GBU-57 is not equipped with an accelerator rocket to increase its impact velocity.
 
It would be reasonable to wonder why the GBU-57 is not equipped with an accelerator rocket to increase its impact velocity.
It would also be reasonable to wonder if the warhead & fusing would be sufficiently robust to survive impact with the worst case [toughest] rock with the added velocity (and function properly).
 
Ironically, one of the reasons Northrop B-49 was rejected was that the bomb bay was too small to contain the nuclear bombs of that era.
It would be ironic if the B-2 had small bays. It does not. You can stuff an 8-round cruise missile rotary launcher in each one.

edit: From the looks of it, each of the two internal bays in the B-2 is about the size of the single internal bay in the B-52, maybe a tad shorter. The B-52's is 28 feet long.
 
Last edited:
The B-2 bays are significantly shorter, but even the B-52 bay would be a little small to accept a booster and a 20ft+ bomb. The other problem is that someone here, I think mkellytx, posted that the MOP uses the carriages for the CSRL as its cradle, and a major alteration to the bombers would have to be made for anything longer.

I suspect rocket propulsion will have to wait for the next generation bomb and B-21 carriage.
 
Maybe it's not a good idea to use a booster rocket, I'm thinking that the extra speed could affect the accuracy of the guidance system. I will cite the example of the kamikaze: the models that achieved the greatest success in their attacks were naval aircraft designed as dive bombers.
 
Maybe it's not a good idea to use a booster rocket,

The idea for using a jettison able rocket booster would be to create a stand-off range version to be launched from a B-52H (It would also use JDAM-ER style folding wing-kit sized for the MOP) so that it could one at a safe distance.

I'm thinking that the extra speed could affect the accuracy of the guidance system.

It would know doubt require some tweaking of the GNC software.
 
It would be ironic if the B-2 had small bays. It does not. You can stuff an 8-round cruise missile rotary launcher in each one.

edit: From the looks of it, each of the two internal bays in the B-2 is about the size of the single internal bay in the B-52, maybe a tad shorter. The B-52's is 28 feet long.
That would makes sense, since both use the same CSRL.
 
The B-2 bays are significantly shorter, but even the B-52 bay would be a little small to accept a booster and a 20ft+ bomb. The other problem is that someone here, I think mkellytx, posted that the MOP uses the carriages for the CSRL as its cradle, and a major alteration to the bombers would have to be made for anything longer.

I suspect rocket propulsion will have to wait for the next generation bomb and B-21 carriage.
The -21 should be able to carry a single MOP.
 
The replacement weapons are boosted.

Do you have a link to any details, please?

Talking about replacements does anyone know how many GBU-57s are left? Given this is a very specialised, expensive weapon with only two aircraft able to carry it I imagine there aren't many in the USAF's weapons inventory.
 

GBU-57 Massive Ordnance Penetrator’s Replacement Prototypes Just Ordered By USAF​

That is one spicy accuracy requirement! 90% of all shots within 2.2m of target, in GPS-denied areas. Definitely going for "straight down the "thermal exhaust port""shots!
 
> GBU-57 Massive Ordnance Penetrator’s Results From Iran Strike Will Inform Its Future

> GBU-57 Massive Ordnance Penetrator’s Replacement Prototypes Just Ordered By USAF

Seems like the results were not satisfactory for the USAF, or at least not in the context of potential future uses of such weapons against the same or more formidable adversaries.
 
> GBU-57 Massive Ordnance Penetrator’s Results From Iran Strike Will Inform Its Future

> GBU-57 Massive Ordnance Penetrator’s Replacement Prototypes Just Ordered By USAF

Seems like the results were not satisfactory for the USAF, or at least not in the context of potential future uses of such weapons against the same or more formidable adversaries.
The primary issue with the MOP is that a B-2 can only carry 2, and a B-21 can only carry 1.

I suspect that the new design is about the length of an AGM-86 or LRSO, and light enough that a B-21 can carry at least 4.
 
The primary issue with the MOP is that a B-2 can only carry 2, and a B-21 can only carry 1.

I suspect that the new design is about the length of an AGM-86 or LRSO, and light enough that a B-21 can carry at least 4.

That already exists; it’s the GBU-72. This clearly is intended to be a GBU-57 replacement, and you likely cannot get the same performance with only 5000 lbs.
 
That already exists; it’s the GBU-72. This clearly is intended to be a GBU-57 replacement, and you likely cannot get the same performance with only 5000 lbs.
Nonsense. The GBU-72 replaces the unwieldy GBU-28 in the package of a 2000 lb JDAM and is meant for the F-15 and likly F/A-XX and F-47.

The primary issue with the MOP is that a B-2 can only carry 2, and a B-21 can only carry 1.

I suspect that the new design is about the length of an AGM-86 or LRSO, and light enough that a B-21 can carry at least 4.
It should be the same length as the bay and no more than 22000 lb. It all depends on the performance but the desired weight is such that 2 could be carried even if overweight.

https://www.airforcetimes.com/air/2...act-to-prototype-next-gen-bunker-buster-bomb/
 
That already exists; it’s the GBU-72. This clearly is intended to be a GBU-57 replacement, and you likely cannot get the same performance with only 5000 lbs.
BLU-109 with a 21" rocket strapped to the back for velocity. Say, like the Mk72 booster used on SM6s. Which should put a 2000lb load to just short of Mach 2 on the drop.
 
BLU-109 with a 21" rocket strapped to the back for velocity. Say, like the Mk72 booster used on SM6s. Which should put a 2000lb load to just short of Mach 2 on the drop.

A very interesting and intriguing idea, Scott.
 
Based on the Matra Durandal concept, minus the parachute since we're not dropping this from 200ft AGL.

I hadn't thought of the Durandal however what you propose would also be a guided-missile as the Mk-72 has thrust-vectoring (Just need to add some tail-fins for stability) with a 21" diameter aerodynamic casing (The BLU-109 is 14.9" in diameter) with tail-fins attached (Maybe jettison the Mk-72 after burnout) and use the JDAM guidance package (With maybe a simple terminal-seeker for aim point selection).​
 
The GBU-72 isn't a pure solid penetrator like an APFSDS, the performance also takes the explosive into account. For the BLU-109 the Prsm rocket motor might fit better.

This new boosted penetrator would be similar to the Sviet 3M54E Klub , in service will all of them except us.
Due to material, impact physics, atmosphere etc. there's a limit to desired impact speed from M2.5-3.5; more would weaken the shell and or break it. In the final stage it needs to pull up and then pull down for increased precision and for slowing down to desired velocity.
 
The GBU-72 isn't a pure solid penetrator like an APFSDS, the performance also takes the explosive into account. For the BLU-109 the Prsm rocket motor might fit better.

This new boosted penetrator would be similar to the Sviet 3M54E Klub , in service will all of them except us.
Due to material, impact physics, atmosphere etc. there's a limit to desired impact speed from M2.5-3.5; more would weaken the shell and or break it. In the final stage it needs to pull up and then pull down for increased precision and for slowing down to desired velocity.
I was assuming a dropped bomb, so no need to pop up or anything. This is dropping in from 60,000ft right into the bunker's ventilation shafts, so proper shaping alone will get the bomb over Mach 1. Once ~10sec from impact the rocket motor can fire to increase the speed.
 
I was assuming a dropped bomb, so no need to pop up or anything. This is dropping in from 60,000ft right into the bunker's ventilation shafts, so proper shaping alone will get the bomb over Mach 1. Once ~10sec from impact the rocket motor can fire to increase the speed.
Excep for the AIM-9 and similar all ordances (included misssiles like the AIM120) are being dropped/ejected.
Ocf I was talking about the bomb's flight path.
 
If that is the case, it seems to reason that it is not ready for combat yet and that you might obtain even more performance from a 20,000 lb store.

No, it doesn’t.

The idea that more boom boom equals more useful damage to the target is an insult to anyone who has ever worked with explosives and still has 10 fingers.

Most of the energy from a “MOP” is wasted. It was always intended to be an interim weapon.
 
Excep for the AIM-9 and similar all ordances (included misssiles like the AIM120) are being dropped/ejected.
Ocf I was talking about the bomb's flight path.
Oh, I had misread what you wrote, I thought you were talking about using it as a missile with a more horizontal flight profile.
 
No, it doesn’t.

The idea that more boom boom equals more useful damage to the target is an insult to anyone who has ever worked with explosives and still has 10 fingers.

Most of the energy from a “MOP” is wasted. It was always intended to be an interim weapon.

Well GBU-57 was still used operationally instead, and the USAF is having a new weapon in that class designed. So it seems any much smaller weapon that is equally effective is likely not in service yet and not intended as a complete replacement when it is.

Mass is not just for HE; any penetrator will need levels of hardness and density, and possibly propellant, that is mass intensive. DU 120mm long rod penetrator has no HE at all, but I would not describe it as light. I remain skeptical equal performance can be achieved at 5000 lbs compared to 20,000.
 
Well GBU-57 was still used operationally instead, and the USAF is having a new weapon in that class designed. So it seems any much smaller weapon that is equally effective is likely not in service yet and not intended as a complete replacement when it is.

Mass is not just for HE; any penetrator will need levels of hardness and density, and possibly propellant, that is mass intensive. DU 120mm long rod penetrator has no HE at all, but I would not describe it as light. I remain skeptical equal performance can be achieved at 5000 lbs compared to 20,000.
Supposedly, the Mk4 RBA shape is an effective ground penetrator if you don't have a nuclear kaboom installed inside. That's about 500lbs, and has a pretty good sized volume for HE inside. Add guidance and add a rocket booster, and suddenly you have a ~1000lb DU earth penetrating warhead in a ~3000lb package.
 
Supposedly, the Mk4 RBA shape is an effective ground penetrator if you don't have a nuclear kaboom installed inside. That's about 500lbs, and has a pretty good sized volume for HE inside. Add guidance and add a rocket booster, and suddenly you have a ~1000lb DU earth penetrating warhead in a ~3000lb package.

Ok, but how deep is it going? There is a penetrator that will do 2 meters of concrete at 300lbs. What weight gets you to BBU-57 performance?
 

Similar threads

Back
Top Bottom