Boeing GBU-57 MOP (Massive Ordnance Penetrator)

NMaude said:
Well, for an off-the-shelf rocket-motor there's the Star family for example specifically the Star 30, Star 37 and Star 48 rocket-motors, they all have high-thrust and long burn-times; there also the Orion 38. For more technical details see Northrop-Grumman very lengthy solid rocket-motor product catalogue. The only thing that would need to be designed would be the tail-fins for stability and an adaptor to mate the booster to the GBU-57.
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They are not for atmospheric flight.
 
NMaude said:
This! The B-52 is still producing the same amount of lift from its' wing and then all of a sudden its 30,000lb lighter.
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That would be my expectation, but I trust the opinion of people who have been there.
 
NMaude said:
The Orion is too big but on the other hand the Star 48 would do (With a nozzle suitable for an atmospheric burn).
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Trying to put a rocket on GBU-57 is putting a hat on a hat. There is a bomber that could do that already.
 
Josh_TN said:
Trying to put a rocket on GBU-57 is putting a hat on a hat. There is a bomber that could do that already.
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I suggested for use so that a GBU-57 could be used in a stand-off mode for the B-52H which is capable of carrying it, a B-2A diocesan;'t need to on the account of its' stealth.
 
NMaude said:
I suggested for use so that a GBU-57 could be used in a stand-off mode for the B-52H which is capable of carrying it, a B-2A diocesan;'t need to on the account of its' stealth.
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I get that. And I think it is unnecessary and never going to generate enough stand off to be relevant in a peer fight
 
Scott Kenny said:
I was not expecting that, you'd think that even with the bomb bay on your CG, suddenly being 30,000lbs lighter would result in a 500+ ft elevation gain.
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When we mission planned it, we half-jokingly guessed one thousand. The entire crew backed Shotgun up. One thing BUFF pilots are really good at is compensating for pitch changes: thrust change, pitch change; spoiler movement, pitch change; fuel movement, pitch change; turbulence, pitch change. Perhaps if it was you or I then there would be some climb, but high time golden hand, rock steady. I did get to run the TPS qual eval profile on Balls 50 from the copilot seat, so this is first-hand experience.
 
mkellytx said:
When we mission planned it, we half-jokingly guessed one thousand. The entire crew backed Shotgun up. One thing BUFF pilots are really good at is compensating for pitch changes: thrust change, pitch change; spoiler movement, pitch change; fuel movement, pitch change; turbulence, pitch change. Perhaps if it was you or I then there would be some climb, but high time golden hand, rock steady. I did get to run the TPS qual eval profile on Balls 50 from the copilot seat, so this is first-hand experience.
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This would be an instant pitch reduction, pretty damn impressive.

But I did react to a really big swell one time on the KY, slammed full dive on the planes and we didn't lose any depth. So I can believe the "really good hand on the yoke" side of it.
 
NMaude said:
This! The B-52 is still producing the same amount of lift from its' wing and then all of a sudden its 30,000lb lighter.
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Warning engineering to follow. The B-2 is a much lighter aircraft than the B-52, the change of mass as a % of aircraft mass is much greater. The BUFF is a 488,000 max TO aircraft, 185,000 empty. The drop was at White Sands so they took a lot of gas, 200,000 lb is a good low-end estimate if they AR'ed after. When I flew from ED to EG to shoot a MALD we were heavier and still took 60,000 lb of gas to get home. So, 185+200+30 gives 415,000 lb at TO, climb to FL350 and M .85 burns a lot of gas let's say 20K, cruise that heavy is 25K/hr with no HSABs, Sky Vector gives me 1 hr 18 min from KEDW to KHMN so let's say 30K then half an hour of dry runs 12K. So, 350,000ish lbs for the drop, which is less than 10% of the weight of the aircraft. How many times do we see an F-16 climb 500 ft when they drop a pair of 2,000 lb bombs? That's a greater % of the aircraft mass than Balls 50 was at release. It's not uncommon for a BUFF to drop 12 GBU-31's rapidly which is a 24,000 lb weight change and that doesn't change altitude.

So, what gives. The lower weight needs a lower AOA to fly, which creates backpressure that the pilot compensates and trims out. Those guys are trained to keep the needles centered, so there was a bump and compensation with minimal altitude change. Also, worth consideration is that you fly these first drops at optimum cruise and altitude. Basically, the aircraft is at its most benign AOA, the aircraft is at its happy spot, the plane wants to stay stable at that condition, which is the very reason first drops are planned for that condition. It is the condition were something bad is the least likely to occur since the aero is at its best spot. That bit of stability contributes to the lack of big change.

Didn't mean to write a book, but did at least did avoid going into summation of forces and moments that didn't require breaking out the USAF TPS EOM block textbook.
 
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NMaude said:
The Fordow facility is a Uranium-235 enrichment plant NOT a nuclear-reactor, Chernobyl was an active nuclear-reactor that was chock full of acutely radioactive fission-products, U-235 is only mildly radioactive (Most the danger from it is due to its' chemical properties as a heavy-metal, while not anywhere near as toxic as Plutonium it is still very poisonous).
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It is excellent news that the sarcophagus is not necessary, so when the European Union decides to pay for the reconstruction of Iran with my taxes, the bill will not be so high. I'm already paying for the reconstruction of Syria and Lebanon, and these guys do nothing but break things.

I have never used the expression nuclear reactor:)
 
Scott Kenny said:
Putting a rocket onto a MOP is already talking about needing to drop from the wing of a B-52.
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Maybe Balls 8 at the North Gate of ED, it's the only one with a reinforced wing, and only on one side. Every other BUFF is basically 25 klbs per HSAB. There's a reason we dropped the first MOP out of the bay. Eight ALCMs is 32,000 lbs plus the rotary.
 
mkellytx said:
Warning engineering to follow. The B-2 is a much lighter aircraft than the B-52, the change of mass as a % of aircraft mass is much greater. The BUFF is a 488,000 max TO aircraft, 185,000 empty. The drop was at White Sands so they took a lot of gas, 200,000 lb is a good low-end estimate if they AR'ed after. When I flew from ED to EG to shoot a MALD we were heavier and still took 60,000 lb of gas to get home. So, 185+200+30 gives 415,000 lb at TO, climb to FL350 and M .85 burns a lot of gas let's say 20K, cruise that heavy is 25K/hr with no HSABs, Sky Vector gives me 1 hr 18 min from KEDW to KHMN so let's say 30K then half an hour of dry runs 12K. So, 350,000ish lbs for the drop, which is less than 10% of the weight of the aircraft. How many times do we see an F-16 climb 500 ft when they drop a pair of 2,000 lb bombs? That's a greater % of the aircraft mass than Balls 50 was at release. It's not uncommon for a BUFF to drop 12 GBU-31's rapidly which is a 24,000 lb weight change and that doesn't change altitude.
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I keep forgetting just how freaking heavy a B-52 can be...
 
Scott Kenny said:
This would be an instant pitch reduction, pretty damn impressive.

But I did react to a really big swell one time on the KY, slammed full dive on the planes and we didn't lose any depth. So I can believe the "really good hand on the yoke" side of it.
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You did catch where I said golden hands right? TPS graduate pilots are exceptionally precise. So much so, that as I worked on that Iraqi aircraft project all of the test pilots I flew with made me fly every low-risk test point. Why? They were so good at compensating (B-52 test pilots, U-2 test pilot) that they made me fly the plane to expose the bad handling characteristics. The rules prevented me from flying medium risk and above test points but read the paragraph below as to why that's a really bad idea. Granted, they also knew I wanted to go to pilot training and TPS, but I digress

The difference between a golden hand and a line "fighter pilot" nearly killed me. The golden hand every time we flew in Iraq took out his grease pencil and made a mark on the windscreen. He used this mark to control pitch and yaw deviations. The line guy used the cockpit instruments, in particular the ball (step on the ball to coordinate flight). Why did the latter almost kill me? Hysteresis, the Mk 1 Mod 0 human eyeball is a far more accurate and precise measure of motion than the fluid filled ball. That little bit of delay was enough to depart from controlled flight, enter a flat spin, which the golden hand saved our lives by performing a non-standard recovery. In the Swiss cheese model, it's not a good thing to get to your last barrier. Learned a lot from that.

About you KY story. The human body is truly marvelous is it not, it senses forces and accelerations better than most instruments. That's why flying seat of the pants is a real thing, literally feeling those forces and accelerations in your butt, hands and feet are better than any autopilot, sorry George :(.
 
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mkellytx said:
About you KY story. The human body is truly marvelous is it not, it senses forces and accelerations better than most instruments. That's why flying seat of the pants is a real thing, literally feeling those forces and accelerations in your butt, hands and feet are better than any autopilot, sorry George :(.
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We called our automatic systems "FRED:" F*ing Ridiculous Electronic Device. But it did work really well, even if it got really twitchy above 10 knots.
 
Scott Kenny said:
We called our automatic systems "FRED:" F*ing Ridiculous Electronic Device. But it did work really well, even if it got really twitchy above 10 knots.
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LOL @Scott Kenny FRED in USAF was always the C-5, which was F@cking Ridiculous Expenditure of Dollars. Which strangely enough led to the C-17's nickname Barney. Flintstones, check, fat stubby aircraft, make reference to fat, stubby, massively annoying purple dinosaur, prefect!

That said, the C-17 is a really nice aircraft to fly. Enough off topic. What more about the MOP?
 
Byeman said:
They are not for atmospheric flight.
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Assuming available motor diameters and lengths suit your purpose, for (near) vacuum upper stage solid motors you might have to tinker with nozzle lengths a bit in order to adjust for ambient pressure/atmospheric environments, but in general solids, silly stupid little roman candle meatheads that they are, really don't care a whole lot about outside conditions (assuming you don't have any pesky O-Ring joint segments, that is) as long as you stay in environmental specs (STS-51-L, anyone?), since as non-airbreathers they don't take it in, they only dish it out with truly reckless abandon.
 
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NMaude said:
The Fordow facility is a Uranium-235 enrichment plant NOT a nuclear-reactor, Chernobyl was an active nuclear-reactor that was chock full of acutely radioactive fission-products, U-235 is only mildly radioactive (Most the danger from it is due to its' chemical properties as a heavy-metal, while not anywhere near as toxic as Plutonium it is still very poisonous).
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Don't forget that a large portion of the Uranium in a processing plant is Uranium Hexafluoride.

It's not just a heavy metal, it's a heavy metal/fluorine compound.... That sublimates at 60 degrees, so a spill outdoors in a hot summer might actually allow for gas to form.

It's dangerous as all hell.
 
MihoshiK said:
Don't forget that a large portion of the Uranium in a processing plant is Uranium Hexafluoride.

It's not just a heavy metal, it's a heavy metal/fluorine compound.... That sublimates at 60 degrees, so a spill outdoors in a hot summer might actually allow for gas to form.

It's dangerous as all hell.
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Where the hell does it reach 60degC on a summer day?!?
 
Scott Kenny said:
Where the hell does it reach 60degC on a summer day?!?
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It's that time of year again where Network Rail is pointing out that some of its rails are bending because on a hot day they can reach 20C hotter than the air temperature.

So there's a potential for sublimation at significantly sub-60C temperatures when UF6 is exposed on surfaces in direct sunlight. Of course it'll promptly cool back down to the solid state again, but you probably don't want to be anywhere close to anywhere there's been a spill in Mid-East summer temperatures as there'll probably be a low-lying cloud of gaseous UF6.

(Mitribah, Kuwait holds the world record temperature jointly with Furnace Creek at 54C).
 
mkellytx said:
The human body is truly marvelous is it not, it senses forces and accelerations better than most instruments. That's why flying seat of the pants is a real thing, literally feeling those forces and accelerations in your butt, hands and feet are better than any autopilot, sorry George :(.
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One reason I wished Starship was winged...

I have seen LiDAR create havoc with smart phone cameras--maybe cause landers to fail.
Any munitions vulnerable to cheapo cameras on a chip?

Shine a light just so to have an explosive go off a tad too soon?
 
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NMaude said:
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.
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I mean, you'd need 36 to bomb up the entire fleet of 18x available B-21s.

I wouldn't be surprised if there were only ~50 made.
 
DWG said:
So there's a potential for sublimation at significantly sub-60C temperatures when UF6 is exposed on surfaces in direct sunlight. Of course it'll promptly cool back down to the solid state again, but you probably don't want to be anywhere close to anywhere there's been a spill in Mid-East summer temperatures as there'll probably be a low-lying cloud of gaseous UF6.
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I doubt that solid UF6 is particularly fun to have around, either. And if it gets exposed to water (including moist air), it breaks down to form hydrogen fluoride and uranyl fluoride, both of which are water-soluble, toxic and corrosive.
 
The number of GBU-57s I do not think is publicly given, though I think the initial order for the first version was 20 and that there have been contracts for additional weapons since. There also was recently an effort to expand production.

Random guess, there’s probably enough to do this a few more times, were it thought necessary somewhere.
 
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Josh_TN said:
Random guess, there’s probably enough to do this a few more times, weee it thought necessary somewhere.
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They're clearly 'golden bullet' weapons procured and intended for preplanned sorties against specific targets. I'd suggest that the number procured is based on the number required for those specific sorties plus a small overhead for maintenance, and possibly a reserve for reattack of some portion of the targets if the first attack were to be unsuccessful.

I'd further suggest that if they're intended for specific targets, there may be individual weapons fine-tuned for particular aim points.
 
DWG said:
Friend of mine used to work with boiling hydrofluoric acid - eeeeek!
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What kind of work was that? I can't imagine what would one would be using boiling hydrofluoric acid but that would have to be exceedingly dangerous to handle.
 
NMaude said:
What kind of work was that? I can't imagine what would one would be using boiling hydrofluoric acid but that would have to be exceedingly dangerous to handle.
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Melting volcanic basalts to feed them though a mass-spectrometer as part of their PhD.
 
bobbymike said:
twitchy.com

Joint Chiefs Chairman Brought Video Receipts That Obliterate Dem/Media Narrative About Iran Strikes

Joint Chiefs Chairman provides evidence debunking media narratives about Iran strikes.
twitchy.com twitchy.com
See the X links for the information
————
From an ex-military X user:

“The fact that General Caine said we had a guy watching the construction of the nuclear sites for 16 years, then made a specific bomb to deal with it…..”
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Wow, General Caine this morning was dynamite. His part of the briefing was masterful, that was expert use of storytelling messaging to be persuasive that separates very good leaders from exceptional ones. Our director of engineering called and insisted that I watch. Just to be clear, I'm not cheerleading a political side, we studied that topic in business school. My admiration is from how hard that is to pull off and come off genuine.

Also, super impressed that all 6 bombs per shaft went down the same shaft. The overpressure from the first bomb on each side blew the concrete caps off of the secondary air shafts. Then the other five bombs per side went down the same hole. The videos were chilling.

Makes me proud to have worked with DTRA to get the first drop pulled off from Balls 50!
 

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