Boeing family of JDAMs

trose213 said:
NMaude said:
True however the AGM-158 is expensive and a powered JDAM would fit the bill where you basically want a budget cruise-missile for a target that is beyond the range of JDAM-ER but doesn't justify the expense of an AGM-158.
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It would be a much shorter range weapon, probably ideal for the B-21.
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If it could fit into a smart bomb rack, then that would get you twenty of them vs 8 on the rotary. But if your just loading a CSRL with them it’s pointless.

ETA: assuming B-21 has a B-2 compatible bomb bay, which is my personal bet.
 
dan_inbox said:
Forest Green said:
https://twitter.com/x/status/1628275379944271872
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"These bombs are dropped from a height of 14 km and fly at a distance of up to 72 km."
Dropped from 46,000 ft ? really ?

Especially above the Ukraine...
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That's more of a "if dropped from 46,000 feet, they can glide up to 72 km." Obviously, you get less range when dropping from lower altitudes.

I stick with the idea that the best approach might be a toss/lofted delivery to minimize exposure to air defenses. It seems in keeping with what little we've seen of Ukraine Air Force weapons delivery. I wonder if it's smart enough to keep the wings folded until the apex of the trajectory.
 
If the 2,000Lb JDAM-ER design could be modified to mount a Mk-135 rocket-booster it could dramatically extend its range.
 
mkellytx said:
Forest Green said:
I would imagine the wings only deploy once the bomb starts falling.
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The SDB’s have logic that keeps the wings folded until subsonic if dropped supersonic, so there is at least precidence for conditional logic.
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Random off topic question, since you have experience in the bomber community. If you can speak on the subject, was SDB ever integrated with the B-2? As far as I can tell there was an intent to do so but never any announcement it had occurred; the matter might be classified.
 
NMaude said:
If the 2,000Lb JDAM-ER design could be modified to mount a Mk-135 rocket-booster it could dramatically extend its range.
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You must have missed this on the last page.

229809-73b1c907353cc1ce05041e875d9a9519.jpg
 
Josh_TN said:
Random off topic question, since you have experience in the bomber community. If you can speak on the subject, was SDB ever integrated with the B-2? As far as I can tell there was an intent to do so but never any announcement it had occurred; the matter might be classified.
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As of 2010 when I left flight test there were no integration or safe separation tests. There might have been some fit checks on the weapons load trainers but that was it.
 
Forest Green said:
NMaude said:
If the 2,000Lb JDAM-ER design could be modified to mount a Mk-135 rocket-booster it could dramatically extend its range.
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You must have missed this on the last page.

229809-73b1c907353cc1ce05041e875d9a9519.jpg
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I didn't, what I'm suggesting is that by mounting on the rear of the JDAM tail-kit (It would likely require some redesign to beef up the structure to accept the booster's acceleration loads) a Mk-135, a Mk-114 Mod 0 (Used to launch the RUM-139 VL-ASROC) or the Mk-72 booster it would create something that has a launch-range between the JDAM-ER and the powered JDAM.
 
NMaude said:
I didn't, what I'm suggesting is that by mounting on the rear of the JDAM tail-kit (It would likely require some redesign to beef up the structure to accept the booster's acceleration loads) a Mk-135, a Mk-114 Mod 0 (Used to launch the RUM-139 VL-ASROC) or the Mk-72 booster it would create something that has a launch-range between the JDAM-ER and the powered JDAM.
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These are all grossly the wrong size for a 500-lb (~225kg) JDAM. Mk 72 alone is 1500kg, and Mk114 is about 900 kg. Mk 135 is closer, but it still weighs ~300 kg.

If Skipper is your model, it had a Mk 78 motor, basically the back end of a Shrike missile. But that only added about 10 klicks to the range of an unpowered 1000-lb Paveway. Enough to keep out of naval AAA but not terribly impressive overall. The wing kit on JDAM ER is already doing more than that. And given how cheap the jet is in powered JDAM, I'm not sure a rocket version would actually save much money.

Edit: Doing the math, the rocket add-on for Skipper was a net increase of about 85 kg for a 450-kg (1,000-lb) bomb payload.
 
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NMaude said:
I didn't, what I'm suggesting is that by mounting on the rear of the JDAM tail-kit (It would likely require some redesign to beef up the structure to accept the booster's acceleration loads) a Mk-135, a Mk-114 Mod 0 (Used to launch the RUM-139 VL-ASROC) or the Mk-72 booster it would create something that has a launch-range between the JDAM-ER and the powered JDAM.
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I'd imagine the plan is to boost it and then deploy the wings.
 
Orionblamblam said:
The explosion is pretty sporty, certainly more than if a relatively small munition set off whatever might be on the roof... unless there was an ammo dump right under the roof, of course.
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Ukraine might have used one of their new larger drones, or there's a generator on the roof, and the Russians left a jerry can next to it. But a 500lber is fairly biblical compared to that. That wasn't even GMLRS level, and a GMLRS rocket only contains 30kg (66lb) of HE, a 500lber contains 192lb.

Here is a GBU-38 test:

View: https://www.youtube.com/watch?v=EL7oeu3_syQ&t=109s
 
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Anyone know what the twitter post and the photograph are saying as I don't speak Ukrainian?
 
NMaude said:
Anyone know what the twitter post and the photograph are saying as I don't speak Ukrainian?
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Google LEns will tranlate text in images but you have to tweak the results a bit. This one says, roughly: "Happy Birthday, Valery Fedorovych, the best GIFT - DEAD RUSSIAN! 07/08/2023" (Google wanted to say 3rd Anniversary, but it's getting confused by the 3 that isn't really a numeral)

The Tweet says this was in honor of the 50th birthday of Valerii Fedorovych Zaluzhnyi, the Ukrainian Commander-in-Chief.
 
Josh_TN said:
There will be 6,000 AGM-158s of all types by 2026. It's a sunk cost. If you don't want waste a new one, use one of the old A models that still heavily outranges powered JDAM. They probably start to expire late decade anyway and might as well be used up. The only advantage I see would be if more could be carried, and since it is stated to take up the same space as a mk84 (though I presume it is lighter), I don't see any way it could be tucked into existing racks or hard points in larger numbers, So the weapon is pointless for USAF; there's no niche to fill.
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High intensity warfare still has a voracious appetite for munitions. In a hypothetical Sino-American conflict that 6,000 will rapidly dwindle, and I’m pretty sure JASSMs can’t be manufactured as quickly as a mk80 series bomb. This isn’t even taking into account any possible brushfire wars/police actions that might eat into the stockpile (remember the multi-year shortfall of TLAMs due to Odyssey Dawn?).

The ability to basically quickly convert dumb bombs into JSOWs for essentially pennies on the dollar seems like something both the USAF and USN should seriously consider.
 
What are the range and cost estimates for powered JDAM? What type of engine was it to use?
 
Josh_TN said:
What are the range and cost estimates for powered JDAM? What type of engine was it to use?
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Cost estimates have not been seen, Boeing talked about 'fractions' of the cost of similar weapons i.e. cruise missiles. But as soon as you put any lo-cost engine in something you add a minimum of $80k to the cost. IF, and its a big if, Boeing could keep close control on costs it could be done for around $150k given the pricing of JDAM in general. Realistically I think $200k would be a reasonable price. Any higher and you start to get into JSOW territory, or questions around making the shape more LO for survivability.

Range was mentioned as 'up to 160nm'

Engine was specifically mentioned as Turbojet. Nothing else detailed. But I think that, in conjunction with the released imagery of it, implies a small turbojet. The Pratt and Whitney TJ-150 would seem to fit the bill and is already in use on the MALD.
 
timmymagic said:
The Pratt and Whitney TJ-150 would seem to fit the bill and is already in use on the MALD.
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Using an existing turbojet in production would further lower the unit cost of the engine especially if its produced in large numbers which would be the case for a JDAM tail-kit (Since JDAM-ER is already used I suppose it would be called the JDAM-LR).
 
NMaude said:
Using an existing turbojet in production would further lower the unit cost of the engine especially if its produced in large numbers which would be the case for a JDAM tail-kit (Since JDAM-ER is already used I suppose it would be called the JDAM-LR).
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www.airandspaceforces.com

Powered JDAM: Boeing’s New Alternative to Cruise Missiles | Air & Space Forces Magazine

Boeing is developing a long-range version of its Joint Direct Attack Munition called the Powered JDAM, adding an engine to extend its range by 20 times over the conventional glide version of the weapon.
www.airandspaceforces.com www.airandspaceforces.com
 
timmymagic said:
Cost estimates have not been seen, Boeing talked about 'fractions' of the cost of similar weapons i.e. cruise missiles. But as soon as you put any lo-cost engine in something you add a minimum of $80k to the cost. IF, and its a big if, Boeing could keep close control on costs it could be done for around $150k given the pricing of JDAM in general. Realistically I think $200k would be a reasonable price. Any higher and you start to get into JSOW territory, or questions around making the shape more LO for survivability.

Range was mentioned as 'up to 160nm'

Engine was specifically mentioned as Turbojet. Nothing else detailed. But I think that, in conjunction with the released imagery of it, implies a small turbojet. The Pratt and Whitney TJ-150 would seem to fit the bill and is already in use on the MALD.
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Perhaps the bigger question (almost certainly unanswerable at this stage) is "how many can you make how fast?". The cost advantage alone doesn't seem to justify it IMO, given the lack of capability compared to AGM-158 (even in the A version). It is much more detectable, has no terminal seeker, and critically has a shorter range. It would be basically unusable by the bomber force given the risks to the launch platform. Even the 158A already has a marginal standoff range for a bomber platform and likely will be relegated to tactical fighter usage in a peer conflict. The main advantage I could see would be quantity, *if* Boeing actually had the capacity to produce hundreds or thousands of kits per year. AGM-158 production capacity is already planned to expand from a 550/year maximum to 850/year. If this kit can't be made at least as prolifically I don't think there's much utility for the USAF.

IMO the B-21 would largely solve the PGM deficit issue by using SDB and wing kits on JDAMs. It can carry these in large numbers, extend their range via very high release altitudes, and get much closer to targets than other aircraft types (a key goal of the program). So a powered JDAM only seem relevant as a near term (this decade) stop gap. If it couldn't be rapidly put into production in large numbers, there isn't a lot of incentive adopt it IMO.

EDIT: also relevant, how soon could it be put into production? If years of development are needed, again, not really solving any problems.
 
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NMaude said:
Using an existing turbojet in production would further lower the unit cost of the engine especially if its produced in large numbers which would be the case for a JDAM tail-kit (Since JDAM-ER is already used I suppose it would be called the JDAM-LR).
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The US has been pursuing a 'cheaper' engine for a couple of years now under the Gray Wolf programme. Kratos purchased Technical Directions Incorporated (TDI) who were working on a cheaper turboject (I've heard, but can't remember where that $40k was an objective price). TDI also made the cheap turbojet engine for the NLOS-LM Loitering Attack Munition. The J85 was the one for Gray Wolf, no relation to the 1950's J85 that was also designed for attritable use....

TDI - Technical Directions Inc

Technical Directions Inc. (TDI) has been developing turbine engine related technologies for industrial and military applications for the past two decades.
tdi-engines.com tdi-engines.com
 
Would a modern day pulsejet be at all practical or cost effective in this role? It seems to me it would remove a lot of complexity and moving parts relative to a turbojet, despite the numerous other disadvantages. Reducing the cost in both money and time of production would be a key enabler in low cost stand off weapons.
 
TomcatViP said:
Notice how the boat sink instantly, leaving no escape to any sailors that would have been onboard. This is terrifying, coming from something as casual and cheap as a guided bomb...
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Keel-breakers are scary weapons. A 2000lb JDAM is also on the order of how much boom is in a Mk48 torpedo, depending on what the exact explosive used in the JDAM is.
 
Josh_TN said:
I was thinking it is better suited to the numerous large civilian ships that would be necessary to support an invasion of Taiwan...car ferries, Ro/Ros, container ships, etc. Wasting a militia fishing boat with a mk84 seems a little...overly dramatic. Though it is probably still perfectly cost effective...
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The submariners would prefer to sink warships or at least large freighters. Tonnage is what counts, not number of sunk ships.
 
Scott Kenny said:
The submariners would prefer to sink warships or at least large freighters. Tonnage is what counts, not number of sunk ships.
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Depends on the conflict and on the objective. A PRC invasion of Taiwan would be relying predominantly on around 50-80 dual use Ro/Ro ferries and car carriers as the backbone of the amphibious lift. This is around 1.5-2 million tons of lift, with most ships being tens of thousands of tons. Compared to a container ship or super tanker, they are about an order of magnitude smaller in terms of displacement. But their ability to rapidly load and unload vehicles without requiring port facilities, some of them even directly into the water, would be an absolute necessity in an invasion attempt. Destroying this class of ship early in a conflict would largely remove any possibility of a successful campaign to take Taiwan.
 
Josh_TN said:
Depends on the conflict and on the objective. A PRC invasion of Taiwan would be relying predominantly on around 50-80 dual use Ro/Ro ferries and car carriers as the backbone of the amphibious lift. This is around 1.5-2 million tons of lift, with most ships being tens of thousands of tons. Compared to a container ship or super tanker, they are about an order of magnitude smaller in terms of displacement. But their ability to rapidly load and unload vehicles without requiring port facilities, some of them even directly into the water, would be an absolute necessity in an invasion attempt. Destroying this class of ship early in a conflict would largely remove any possibility of a successful campaign to take Taiwan.
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Yes, those would be high priority targets. Submariners aren't stupid, just crazy. But once those are gone (3 subs should do the trick), then it's time for the big stuff.
 
Scott Kenny said:
Yes, those would be high priority targets. Submariners aren't stupid, just crazy. But once those are gone (3 subs should do the trick), then it's time for the big stuff.
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Penetrating to invasion beaches (or attacking the invasion fleet on route) is quite apparent for the opponent, so probably it will have redundant levels of ASW.
Experience of submarines interfering with landings, in this case, is pretty disappointing - there is iirc no single case in history where subs worked against a significant landing. Dutch and Germans tried it.

Thus i guess topic of this topic - and will its carriers get a chance to get close enough to, say, mine the invasion beach, - is realistically far more relevant than subs.
 
Josh_TN said:
Would a modern day pulsejet be at all practical or cost effective in this role? It seems to me it would remove a lot of complexity and moving parts relative to a turbojet, despite the numerous other disadvantages. Reducing the cost in both money and time of production would be a key enabler in low cost stand off weapons.
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