Bunker Buster

uranium is also pyrophoric, Tungsten is not.

It's about density, (the sum kinetic energy is mass times velovity) - not about ductility.

The penetration tip can have a dense core surrounded by a very hard casing such as Vidia (tungsten carbide).

If the penetrator is too brittle, you won't generate the pyrophoric jet of molten metal which actually does the penetrating. the penetrator will shatter instead of becoming a jet of superheated plasma.

Absolutely pure (as in zone-refined) tungsten is ductile. The slightest contamination and it becomes brittle.

Tungsten is more dense than DU, but not by much. Btw, depleted uranium is also pyrophoric. Machining the stuff without coolant and you risk a fire. Fine uranium dust can burst into flame spontaneously.

When fired as a sabot round at an armoured tank, for example, the impact does several different things at once, all of them nasty: Anything loose on the interior side of the impact site spalls off at high speed, turning it into shrapnel. The occupants are deafened. Meanwhile most of the round's kinetic energy is converted by the impact into heat, melting the projectile. Because the round's initial shape is optimised for poking holes through armour plate, the molten DU is injected into the armour by enormous hydrostatic shock, often shattering what's beneath. If entry is gained, the molten DU proceeds apace through the armour, tank wall and on into the interior, spraying the occupants with molten metal that immediately bursts into intense flames, burning them alive and consuming all the oxygen. Thump, roast and suffocate. You can't say we're not making progress.

Yep, the Plasma Jet from a DU round (not just from a tank Sabot round....add 30mm DU rounds from A-10's, DU rounds from the chain gun of an AH-64 Apache, and the 25mm DU rounds from the Bushmaster mounted on a M2/M3 Bradley IFV) can punch nasty holes in armor. EVERYTHING burns inside because of it, hence the term "Crispy Critters", meaning what remains of the crew, which isn't much in most cases. Imagine a tank driver (what remains of him) sitting in his seat, minus his head, chest ripped open with all all ribs exposed, on top of being totally burned to a crisp like overdone pork ribs on the gas grill. That my friends, is what happens....and it isn't a pretty picture. Modern weapons are extremely reliable, accurate and very deadly....count on it. Your chances of surviving the modern battlefield for a given length of time with equally opposing weapons capabilities and strengths, are slim-to-none. Gruesome, eh?

The affects rendered from a DU round are horrific. You do not want to view the contents of a tank or APC hit by one. Unfortunately, I witnessed such things during and after Desert Storm and they're permanently etched into my gray matter for the rest of my life. Frankly, you do not want to view such things, ever.

On many occasions, I did observe that DU rounds passed right through one side of an Iraqi T-62, T-72, or T-80 and out the other side.....jagged burned bore holes. In one instance, I saw where it struck the frontal slope of the tank body, where it is the thickest, and pass right out the back end through the engine block! Everything cooked off inside that T-80! ACKKK!!!!

Going Off topic.

They use DU in the A-10 for tank busters just from the KE effect. The rest is a bonus.

With the Avenger Gatling is capable of firing Depleted Uranium at the rate of nearly 12 tons per minute per gun.

Yes, I know all about the Fairchild A-10A Thunderbolt II (aka Warthog) and it's GAU-8/A Avenger gun....a 30mm gatling gun that the plane was built around.

If fact I have both a Tungsten and DU round from the gun here at the house, sitting on one of my office shelves....

Here's some fun facts about the GAU-8/A:

The GAU-8 itself weighs 620 pounds (280 kg), but the complete weapon, with feed system and drum, weighs 4,029 pounds (1,828 kg) with a maximum ammunition load. It measures 19 ft 5 ¹⁄₂ in (5.931 m) from the muzzle to the rearmost point of the ammunition system, and the ammunition drum alone is 34.5 inches (88 cm) in diameter and 71.5 inches (1.82 m) long.^[5] Power for operating the gun is provided by twin 77 hp electric motors. The magazine can hold 1,174 rounds, although 1,150 is the typical load-out. Muzzle velocity when firing Armor-Piercing Incendiary rounds is 3,250 feet per second (990 m/s), almost the same as the substantially lighter M61 Vulcan's 20 mm round.

The standard ammunition mixture for anti-armor use is a four-to-one mix of PGU-14/B Armor Piercing Incendiary, with a projectile weight of about 15.0 oz (425 grams or 6,560 grains) and PGU-13/B High Explosive Incendiary (HEI) rounds, with a projectile weight of about 12.7 oz (360 grams or 5,556.25 grains)^{[citation needed}]. The PGU-14/B's projectile incorporates a lightweight aluminum body, cast around a smaller caliber depleted uranium penetrating core.^[6] The Avenger is lethal against tanks and all other armored vehicles.

GAU-8 mounted in A-10

A very important innovation in the design of the GAU-8/A shells is the use of aluminum alloy cases in place of the traditional steel or brass.^[7] This alone adds 30% to ammunition capacity for a given weight. The shells also have plastic driving bands to improve barrel life. They are imposing to examine and handle, measuring 11.4 inches (290 mm) in length and weighing 1.53 pounds (0.69 kg) or more.^[5][7]

The Avenger's rate of fire was originally selectable, 2,100 rounds per minute (rpm) in the low setting, or 4,200 rpm in the high setting.^[8] Later this was changed to a fixed rate of 3,900 rpm.^[9] In practice, the cannon is limited to one and two-second bursts to avoid overheating and conserve ammunition; barrel life is also a factor, since the USAF has specified a minimum life of at least 20,000 rounds for each set of barrels.^[10] There is no technical limitation on the duration the gun may be continuously fired, and a pilot could potentially expend the entire ammunition load in a single burst with no damage or ill effects to the weapons system itself. However, this constant rate of fire would shorten the barrel life considerably and require added barrel inspections and result in shorter intervals between replacement.

I felt the A-10 is the most beautiful, ugliest piece of equipment we have. Diffently it was built for one thing, and the one thing it does very well.

There is something I like to add, I understand that the recoil of the Gatling gun is higher than the thrust of the A-10. e.i. by firing the Avenger, it actually slows the A-10 down drastically in flight. That is amazing.

I understand that is an Old Wives Tale.....

My old college roommate was an A-10A pilot, first with the USAF 355th TFS (Myrtle Beach AFB), then followed with serving the 174th TFW, NYANG, "Boys from Syracuse". They flew them for over a decade before transitioning to the F-16A in the late 80's.

This response to that sort of statement was "BULLSH*T". I kid you not.

I stand corrected, I see my mistake, the recoil force of 30MM gun exceeds the dry weight of the aircraft. But when fully fueled and fully loaded with ammunition the mass and factoring in momentum the aircraft traveling at 300+ MPH it does not play that much of a factor.

But I still stand behind that the A-10 is the most beautiful ugliest plane in the arsenal

Yes, it IS Mufugly, but in a sense beautiful as well.

Republic/Fairchild really designed a winner!

It's too bad that the USAF "Zoomies" want to kill the A-10A! And replace it with Fast Movers? They're not as accurate on weapons delivery nor can they loiter as long as an A-10A! Just like the SPADS (Douglas AH-1 Skyraiders) used in 'Nam.

It makes no sense to me whatsover!

what they need to do is restart production of the A-10 and give it a whole new avionics suite and maybe newer higher bypass ratio turbofans like boeing is using on their newest generation of airliners to save on fuel for longer loitering time. But that would make entirely too much sense....

I think the military strategists think remote pilot weaponized drones and the AC-130 Spectre gunship will perform the lingering ground support role of the A-10 Thunderbolt and the Douglas AH-1 Skyraider. But that's only the wild guess of a civilian observer outside of the loop.

The AC-130 Spectre is way too vulnerable in high threat environments, especially when there's shoulder-fired SAMs present, like the Soviet-built thermal seeking Grail-11 or better.

The USAF lost one to an Iraqi Grail during the Persian Gulf War. Since then, capabilities has been vastly improved and more deadly due to technological advances by the Russian Federation weapons designers.

I'll buy that a very hot theater would be a poor choice for a Spectre. So if the Spectre is out for this type of operaion, do you think that the UAVs are up to it?

A lot of "what if's" maybe....

I depend probably if it at a high enough altitude to go unnoticed by ground forces equipped w/ shoulder-fired SAMs.

I don't know the stealthiness of UAV's, but it is probably safe to assume they're made of carbon fiber/composite materials that significantly reduce the radar signature if painted by the enemy's defenses. If they are, if would be a pretty good weapons platform to use in a hot territory that's occupied by a well-armed enemy force. Putting manned aircraft can be a costly thing to do.....losing a pilot and/or crew + the a/c would be very expensive. The initial training of a fighter pilot now days is well over a few $Million, and that's not including following training that is needed throughout the pilot's career. Same goes for the crew, but to a lesser amount.

That may well, be, but there is simply no way the current crop of UAV's can hold a candle to the devastation a Spectre or Spooky can unleash with it's aerial artillery. and tank killing for a UAV is likely to be a one at a time thing. they can carry only so many missiles after all. And missiles cost a LOT more than artillery shells do...

That is a current limitation for UAVs (or more properly, Remote Piloted Vehicles (RPVs)). They do not carry a large armament.

Newer generations of RPVs are supposed to address that. Right now they are mainly surveillance and little spot jobs that need a one or two punch rather than a full war.

You might as well just outfit an A-10 with remote controls...

Now that would be an interesting project!

Geeee, can I be the first to fly it RC????? PLLLEEEEAAASSSEEEEE!!!!!!

I worked several years back with a mechanical engineer involved in the design of the Republic A-10 in Farmingdale Long Island. He claimed that the idea that the Avenger's recoil exceeded the engine thrust is a misapplied mixing of the capabilities of the A-10 design, particularly the high lifting capability of this plane. Unlike most fixed wing military birds, the A-10 is originally designed to linger at low altitude over a battle field. The throttled back engine thrust required to keep this plane above stall speed is less than the recoil of the Avenger. (I think that this was with full flaps.) I think under these flight conditions, the 37mm cannon on the P-40 also exceeded the propeller thrust.

On a related note... (those who don't want to listen to old tech stories from back in the 70's can skip along now.) When I worked on the old F104, I was a little surprised that the F104 engine igniters would fire every time the gun was fired. Apparently the smoke from the cannon would choke out the engine, shutting it off every time you fired the gun. I always thought this was a serious engineering flaw, but perhaps the fix (ignition sequence engaged) was the correct fix since I never heard of a 104 crashing just because it fired its guns. Lots of other reasons for it to become known as the "widow maker", but not that one. (moving the A of A vane of most aircraft would fire them as well...an annoying thing when you have the thing jacked and are working in the guts of it. The 104 used a stick kicker in lieu of ignition sequencing for attack angle recovery, but I may be misremembering...its been awhile.)

I do know the F104 was known to overtake and fly into its own bullets. A piece of metal with a hole in it is (or was) on display in the hangar at Cold Lake Alberta, and the story was that it was made by one of its own bullets. Apparently richochets from the range were not uncommon, but this one was made from way up in the sky. That was the story, and I saw no reason for them to lie to me. Much more interesting was the surprisingly large collection of lower radio antannae which were ground off from proximity to the runway. They are only, what 14 inches long when new? Canadian pilots are a bold bunch.

I have no fond memories of that airframe.

Thanks Yusef for that bit of CAF CF-104 Starfighter history! Very interesting.

Not only did the Starfighter shoot themselves down when they fired the cannon at supersonic speeds, other Century fighters did as well.....like the F-105, and the F-106.

Of course the same happened to the F8U Crusader, A-7 Corsair, and the F-4E, F-4F, F-4I, and F-4J Phantom II so equipped with the M-61 Vulcan 20mm cannon.

I love the old CF-104 Starfighters, whether they sported BMF or that gorgeous camo scheme! CLASSIC!!!!!!!!

There's one sitting on a pole at the Canadian Warplane Heritage Museum in Hamilton Ont........the best man in my wedding works there! That baby is a glistening gem!!!!!

Moose, just be aware aluminum+DU=Neutron Source. DU is an alpha emitter, Aluminum when bombarded with alpha particles give off a shower of neutrons, not as much as beryllium does, but enough to be an issue long term.

I CAN say that the nosecone of these bunker busters is neither U-238 nor Tungsten, at least not elemental Tungsten. There is certainly tungsten in the alloy however. Tungsten by itself is too brittle. Wyman Gordon forges them here in Houston.

No no no.
Flint, held onto the shaft with pine resin and then bound on with sinew.
Del

If you wait long enough.

"I believe the material of choice is spent Uranium. (of course there is no such thing)"

I think you mean "Depleted Uranium" which is primarily ²³⁸U. Basically it's the normal uranium that's dug out of the ground with the fissile isotopes of ²³⁵U and ²³⁴U removed. ²³⁸U can fissile but the rate at which this happens is extremely low and it's also impossible to remove all the ²³⁵U and ²³⁴U so there will still be a certain amount of residual radiation albeit at considerably lower levels than naturally occurring uranium.

Whether or not the remaining radiation is a hazard to one's health is open for debate, but uranium is a toxic heavy metal and if ingested, inhaled or pieces find their way into the body you can have problems so it should be handled like any toxic heavy metal with care.

Basically if you work out the half life, it never quits. I worked on the Peacekeeper. All tips were spent uranium. ( OK, so i lost my secret clearance when i left Boeing, so let the FBI come after me).

"All tips were spent uranium."

Were they spent uranium that had come from the core of a nuclear reactor or depleted uranium that is a by-product of the enrichment process needed to make fuel for nuclear reactors?

Somehow I doubt they were spend fuel that has come from the core of a reactor as that remains extremely radioactive for hundreds of millennia and is a major problem for the nuclear industry.

depleted uranium

depleted uranium is merely the "leftovers" from the enrichment process. it is "depleted" of U-235.

As RAMConsult pointed out there's nothing new here, Barns Wallis built two similar bombs that were used during WWII called the Tallboy and Grand Slam that were designed to penetrate deep into the ground before detonating. The idea being that with a surface explosion most of the energy is dissipated in the atmosphere which is compressible while ground, rock and concrete is fairly incompressible and thus a subterranean detonation results in more damage.

As for making it go faster when it hits the ground I think the major concern here is getting the explosive charge and detonating mechanism to survive. The Grand Slam from WWII was said to travel close to or slightly above the speed of sound when it impacted the ground which is sort of the velocity were talking about with the GBU bomb.

Anyway, I'm pretty sure that the limiting factor for the impact speed is the ability of the bomb part to remain intact and operational. Also remember, it's not the impact with the ground that's causing the damage but rather the detonation of 2,700 kg of explosives that's inside the 15,880 kg bomb.

Which raises another point, with the Grand Slam the total weight was 10,000 kg of which 4,144 kg or about 41% was explosives. However with the 15,880 kg GBU only 2,700 kg or 17% is explosives. To my way of thinking they would be a darn side better off going back to Barns Wallace's original designs and using them because they would definitely get more bang for their buck and probably get pretty much the same penetration effect as well.

In summary, I think the limiting factor here is the integrity of the bomb and making it go faster would probably cause the device to disintegrate when it hit the ground rather than penetrate it and detonate below the surface, under or within a bunker.

Same explosive?

The Tallboy and Grand Slam used torpex and I'm assuming that the bunker buster would use C4. Unfortunately I couldn't find any comparison between the two and comparing explosives is a complex task and is very much dependant on the application and how it is used. However, I think we can assume that C4 is considerably more powerful than torpex as torpex is no longer manufactured.

However, that wasn't my point, my point is that with Barns Wallace's Grand Slam 41% of the bomb's total weight was explosives while with the Bunker Buster only 17% of the bomb's weight is explosives. To me if you used C4 in the grand slam you would have around 4,000 kg of explosives compared to the Bunker Busters 2,700 kg which would mean that on a direct comparison of explosion the Grand Slam would be more powerful and generate a greater subterranean shockwave than the Bunker Buster.

Having said that, the Bunker Buster is supposed to penetrate further which means it would need considerably more reinforcing to protect the explosive component of the bomb.

At a guess and that's all it is I would say that the effective explosive component of the Grand Slam from WWII with its torpex filling and the Bunker Buster with modern explosives would probably be similar.

If somebody out there can find a comparative data on explosives then I would be very interested in seeing a proper comparison rather than just my guess.

Nope, the MOP definitely does not use C4. It's a more exotic explosive compound, but I cannot discuss it......

I had an idea that it would be something more exotic, enough said.

I believe everyone here is missing a very important fact in that you cannot place weapons of any sort into space/orbit, because there are International Treaties in place that prohibits our country and others (signed back in the 1960's) that prevents us from doing so. We signed it, so did the Soviet Union and most other countries.....in fact, most UN chartered countries have signed it.

So, the game is up about launching the MOP from space folks.

Please define space.

At what altitude does space begin?

Does orbital have to mean at least one complete orbit?

How the hell do I know where it begins and is defined in the treaty?

I, for one, haven't read the entire thing you know, as it's very long. Be my guest reading it yourself. I'll even give you the link if you want to read it!!! BORING!!!!

I'm sure that the definition of what constitutes the limit of where our atmosphere ends and space begins is probably contained in the treaty somewhere, based on the established science of the day, all based on universal agreement of the contributing signers.

Symantics........

"At what altitude does space begin?"

At the Kármán line which is at an altitude of 100 km.

Space: Is the distance, between you, and another!

Spy Cam's are O. K.

Keeping Earth, the pit of the universe... ( no space distruction, before we get there.)

Wisdom Vs. Criminality ... ( Wisdom has lost too many times!)

This is a follow-on to my previous post:

The treaty that I was referring to was the "TREATY BANNING NUCLEAR WEAPONS TESTS IN THE ATMOSPHERE, IN OTHER SPACE AND UNDER WATER", entered into force by the signing countries on October 10, 1963.

While the primary emphasis of the treaty was the prohibition of nuclear weapons being deployed in space, it specifically outlaws ALL military weapons. It's a fascinating document if you have the time to read it.

[Do you see me wearing my "Thermonuclear sunglasses?! LOL]

Keep out Military? Like; Swat, you can't come in...

Rules of war? [ WAR HAS NO RULES!]

Yes, there are no rules in war. We only can fall back on the Geneva Convention, IF it is adhered to by the warring parties.

But that is beside the point relative to the current thread, essentially rendering you points moot and totally unrelated.......

If it is adhered to by the warring ( battleing ) parties... Like Gloves in the ring!

We are at the edge of Earth Disinagration... Come-on... Politics is bad enough!

I had the idea that two bombs would be better than one, with the smart bombs it should be possible to have one penetrate and explode, to be followed by another to penetrate and explode. The first could be primarily, a penetrator and secondarily an exploder and the second, primarily an exploder with some penetration capability.

passington, that is an excellent idea......the military is currently looking into 2-stage KE penetrators as far as I know, just based on what I have read so far. But no of us is privy to that Top Secret info.

Pretty much along the same lines as the anti-tank HEAT round fired by the M-1A Abrams MBT 120mm smooth bore cannon. It first defeats any "reactive armor" on the targeted tank, then the 2nd stage (via a plasma jet because of a shaped charge) bores through the steel armor. There are 120mm SABOT KE penetrating rounds currently in development that feature a 2-stage, either made of Tungsten or DU.

Yes, modern weapons systems are far far more deadly today. I for one wouldn't want to be sitting in a Main Battle Tank of APC because you're a sitting duck and essentially "toast".

Toast sprinkled with shrapnel!

Yeah, toast that's spiked with molten steel and spalled steel from the inside of the armor, all due to the "plasma jet". Everything inside burns, including bodies, paint, plastics, and any ammo that cooks off.

I've seen it first hand during Desert Storm......the insides of Iraqi Republican Guards MBT's and APC's were toasted....with Crispy Critters inside. It is not a pretty sight. God awful way to instantly die. You essentially have no warning of your impending doom. Lots of expended KE laying about (DU) from 30mm rounds thanks to the A-10's, 25mm rounds from our M-2 Bradley Bushmaster chain guns and Apache's + the 120mm tank rounds.

I thought the whole shenanigan was to avoid the use of nukes in the first place

Yuval, in theory yes, but if the US continues to sit on it's hands, Israel will be given no choice but to go it alone. But Israel does not have access to these MOP penetrators or the means to deliver them (B-2 or B-52 bombers). what Israel DOES have access to are nuclear tipped cruise missiles in German-built diesel-electric subs, and unfortunately nukes are not very good at destroying deep hardened bunkers. They ARE very good at destroying population centers however. so by sitting on our hands, we are ensuring that the coming confrontation has a high probability of going nuclear.

Don't forget the B-1B Lancer Strategic Bombers. My son, a member of the USAF Security Forces is currently guarding them at Dyess AFB in Abilene TX. They can carry more ordinance than either the BUFF and B-2 Spirit....

but they can't carry the MOP. it won't physically fit. I'm not 100% sure it will fit in a -52 to be honest. the B-2 is the only plane I KNOW it will fit. and no, the Lancer can't carry more than a BUFF or a Spirit.

http://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress

http://en.wikipedia.org/wiki/Northrop_Grumman_B-2_Spirit

http://en.wikipedia.org/wiki/Rockwell_B-1_Lancer

http://en.wikipedia.org/wiki/Massive_Ordnance_Penetrator

Rorschach, sorry to inform you that your assessment of each aircraft's maximum bomb capacity is not correct.

The B-1B Lancer has the largest weapons capacity: 75,000# Internally in 3 bomb bays (100-750# Mk 82 bombs) + 59,000# Externally on 6 under-fuselage pylons (118-500# Mk 84) for a Total weapons payload load-out of 134,000#.

The B-52H Stratofortress has a maximum weapons payload of 70,000# from 84 x 500# Mk 82 in the 2 bomb bays + 28 x 750# Mk 84 on two wind mounted weapons pylons (if so equipped). this is the same payload of the B-52D air frames modified for ARC LIGHT missions during he Viet Nam War. Obviously, the "D" model has been retired to the Bone Yard for some time now.

The B-2 Spirit has a maximum internal payload of only 40,000#.

source:

ww.airforce-technology.com

Verified by my kid brother, a Retired USAF/NJANG F-16C Command Pilot, who happens to own an extensive Military aviation library...

[wikipedia is useless, and contains many discrepancies and incorrect data]

Since we're currently on the subject of military aircraft why don't we switch gears and do something on the pilots....

Now, for your listening and viewing pleasure folks, I am presenting to you a little pilot ditty by one of my favorite TX bands, "Dos Gringos":

http://www.youtube.com/watch?v=MYLPoTNnKAk&feature=share

[my kid brother, a retired F-16C pilot turned me onto this band several years ago....ENJOY!!!!!]

The song is entitled "I am a Pilot".

Since we've been on the subject of bombing the crap outta Iran, here's another appropriate song by "Dos Gringos":

http://www.youtube.com/watch?v=fpAUSjvZ2-U&feature=related

[jeepers, no Mushroom Cloud emotioncon???????????]

"Don't forget the B-1B Lancer Strategic Bombers."

One of my favourite aircraft and I have a ¹/₄₈ scale model of one hanging from the ceiling. In my humble opinion It's also one of the most underrated aircraft of all time.

If it's a 1/48 scale plastic model, then you have the Revell-Monogram kit there? Did you build it Masu? What camo version????

I've built several of them over the years. The last one I did build won 1st prize (multi-engine modern jet bombers category) in the IPMS-USA Region I model show & contest here in 2007. I sold it on Ebay for $1,200 USD to a group of B-1B pilots from Ellsworth AFB that were presenting it to the Wing Commander who was retiring. In hindsight I wish I had kept it, but there was no room to display it in my already crowded office!

I added a lot of aftermarket resin and brass PE + scratch-built parts to it to make up for the kit's failings. Painted it in Euro I camouflage and added aftermarket decals (kit's decals are awful!).

Here's the only surviving pic of it (at the IPMS show):

ENJOY!

Very pretty.

Why thank you Yusef! I tried my best on that one model. I must say it was a crowning achievement for my modeling career....and the first time I had used a very expensive Iwata double-action airbrush! The paint turned out better that I had hope, but i have to be honest with you, I had to repaint it 2 times because I wasn't happy with the initial attempts.......

I've always loved the B-ONE, especially in the Euro I "Lizard" camo scheme. the plain Jane ACC Gray that's painted on the God Scale B-1B's just doesn't do it for me!

I have a ton more military jet models pics, mostly fighters, if anyone wants to see them. Any takers? Some of them even won 1st Place at the IPMS Nationals in their respective Categories, and most are 1/32 scale, which is HUGE!!!!!

Indeed. That is one graceful design. Usually, military aircraft are very ugly. Their purposeful design leaves the result out of grace. Not this one, and it's swept-wing design only enhances this grace. It's a Boeing isn't it ?

Agreed, of all the aircraft I've seen, the B1B, the F-5/T-38 and the derivative F-20 tigershark are among the most beautiful I've ever seen.

the XB-70 Valkyrie was also quite beautiful

I saw the only surviving one at The Museum of the US Air Force at Wright-Patterson AFB in Dayton OH. It was absolutely incredible, and very beautiful as well!

Been there twice and will be going back again.....and I will leave Mrs. Moosie at the hotel too!

saw it myself while it was on loan to the Lone Star Flight Museum in Galveston a decade or so back... VERY impressive...

Please, please, please photos by the hundred next time you visit.

For sheer "How did they do that?" awe I still love the now retired X29.

And don't forget the now retired F-111 Aardvark series, including the SAC medium Strategic bomber the FB-111A SACVARK. Now those were beautiful as well!

Here's a FB-111A Aardvark in SAC SIOP camo from the late 70's to mid-80's:

My buddy Philippe Colin from Montreal, who took this pic at Plattsburgh AFB, home of SAC's 380th Bomb Wing (BW). The base was closed in '95. Most of the Varks ended up in the Boneyard, but some that had been converted to F-111G (serving w/ TAC) were later sold to the Aussies who were operating the F-111C Aardvark at the time.

F-111C = FB-111A for all intensive purposes. I bet even Masu knows these Bad Boys!

Beautiful, isn't she? Swept wings and Terrain Following Radar (TFR) scared the living chit out of the Ruskies.....

Eh, The Aardvark never really "stirred my loins" the way the others did... BYMMV... it was that wasp waist that did it to me every time... like a curvy woman in a corset... Er...excuse me for a bit...

I think you'd be very impressed if you were sitting atop an Adirondack mountain summit eating your lunch w/ your girlfriend and out the corner of your eye you see a pair of FB-111A's coming straight up out of the valley below, using Terrain Following Radar (hard ride I might add) at 600 MPH +, wings almost swept full back and both engines in full military power......loop over you at 200 feet AGL, and then back into the next valley. I kid you not, neither of us could hear much for the next 3-4 days! The roar was probably in excess of 130 dB...

Yeah, they even had the 750-gal wing tanks hanging from them as well (see the FB-111A pic) as at least 6 x SRAMs apiece dangling form the weapons pylons. Looked like live nukes to me because I didn't see any "Training Blue" painted on those puppies!!!!!!

Those FB-111A originated out of SAC's Plattsburgh AFB. It happened in July of 1980, right after I bugged-out of the Active Duty Army.

I only wish to this day that I had a camcorder back then to videotape that event, but cheap camcorders were non-existant back then!!! I guess I'll have to rely on my memory banks!!!

Impressive isn't the word I was looking for....it was much more than that!

[what? There's no emotioncon for "Impressed beyond belief"????]

Oh, I don't doubt the impressiveness of that. That could also be said of most modern fighters competently flown... the F-16 and F/A-18 and F-22 as well (the F-22 will be showing off at the Wings over Houston airshow this year, I am going to try to go this year despite having to prepare to run the election on the 6th, to see it.) but my point was just on how they look sitting on the tarmac. The lines "speak" to me in ways other planes don't. It is an artistic thing. sort of like how a '70's stingray body style speaks to me in way that an '80's Vette doesn't. it is how the fenders flare that does it.

Here's a pic of my most favorite FB-111A nose art, from a/c #68-0274 "Missouri Miss", once piloted by a friend of mine, Maj. Frank Bahere (Ret.). This pic is from his personal collection. Ain't she a living doll? It was painted on the Starboard side of the aircraft fuselage, right behind the WSO canopy door.

ENJOY!!!!!

Those lines speak to me in a similar manner...=b

Thought that would get your pulse up some! ;-)~

Enjoy that airshow if you go! Wish I was going!!! I have yet to see the Raptor up close and personal....

Oh, beautiful!

"I bet even Masu knows these Bad Boys!"

Yep I sure do.

Many years back I was working on the control panel in the main control tower for a pretty much fully automated coal mine. The room was organized with consoles in a circle facing inwards so the operators could see out the windows and visually confirm things were going OK.

Anyway, I had my head buried in the back of one of these consoles when I believed I had fixed the problem and stood up looking in the opposite direction to the mine operators.

I got "Shi" out before two of the buggers went by about 20 feet below us on either side of the tower with the wings back and afterburners going full strap.

I don't think they were going faster than Mach 1 because we didn't end up with a whole stack of broken windows but we definitely didn't hear a thing until they were at least level with the tower.

The operators didn't know what had hit them and mugs of coffee went flying in all directions, fortunately away from the consoles.

In Australia the F-111s earned the name "PIGS" not because they were a pig to handle but because they had a big nose and like rooting around at low level.

I also saw footage of one doing a low level pass at supersonic speed over a dam in the snowy mountains scheme. I kid you not, but this guy was so low that he had to climb to get over the dam wall with the reservoir full to the brim. You could actually see the shockwave in the water.

If anybody's interested here's a video clip of what is arguably the top 10 low pass fly bys, the last guy's definitely doing more than Mach 1. This video of a flight over Morocco is also worth a look.

Finally for the piece de resistance that beautiful photograph B1-B pushing it through the sound barrier.

The burst of water vapor is not a sign of passing through the sound barrier. It seems this is a common misconception.

You get this effect when passing through a higher density of water vapor in the atmosphere and you do not need to be going super sonic or even close.

I got the same shot at the Dayton Ohio air show of an F/A-18 passing at low altitude just at the edge of the crowd. It makes for a very dramatic picture if you time it right.

You can actually have air travelling past the aircraft in excess of the speed of sound while the aircraft is still subsonic. When this happens you get a sudden drop in pressure behind where the air is travelling faster than sound and you can get condensation walls like this.

However, if you do see it happen as shown in the photograph you can be pretty sure that the aircraft is travelling very close to if not past Mach 1.

You also don't always get the condensation barrier when an aircraft travels faster than the speed of sound. It's all dependant on the relative humidity and how much beyond the speed of sound the aircraft is travelling.

Which brings me to a problem called sonic stall. As you get close to the speed of sound the air travelling over the top of the wing will be accelerated and if it exceeds the speed of sound it can form a shockwave that dramatically reduces the amount of lift the wing is creating.

Now as you gain altitude the speed of sound reduces due to the reduced density of the air. Also the stall speed of the aircraft increases for the same reason. If you are in an aircraft that can fly extremely high you can find yourself in a situation where if you increase your speed you will cause a sonic stall while if you decrease your speed you will cause a normal stall. Either way you end up stalling the wing and dropping from the sky like a sack of potatoes. This is called coffin corner because you're pretty much stuffed no matter what you do.

Not all aircraft can fly high and fast enough to find themselves in coffin corner, but I believe the iconic U-2 is one of them and when at its operational altitude the airspeed has to be kept within a window of about 5 knots.

Interesting information. Thanks.

Is there consensus that boosting a projectile to altitude in order to increase it's speed during the last 1/2 of it's trajectory (ostensibly to increase penetration potential of a generic bunker buster) is a faulty theory? That energy (if it is, as the OP postulated, to increase velocity) could be more effectively utilized by propelling the projectile, or by exploding an increased warhead? Very nice question, have yet to see much science, but lots of great info, experience, etc.

yes because you are fighting air resistance both going up and going down. secondly these rockets are typically solid fuelled and therefore cannot be throttled or relit. once they are lit, they are going full tilt until they burnout. so unless you have a complex multi-stage setup, you can't fire it going up, and then fire it again going down...

Ok here's the science as I see it.

Let's assume that the bomb has been dropped from a sufficient altitude to reach terminal velocity. In this case increasing the bomb's altitude with rockets after it's released from the aircraft will not add one single Joule to the bomb's kinetic energy at the point of impact. This is because the bomb had already reached terminal velocity so no matter how much higher it goes before commencing its descent the speed at which it would impact the ground would be the same.

Ok, if we used the rockets so that they fired after the bomb has reached terminal velocity then this is a whole new ball game. In this case the velocity of the bomb will be increased and provided there isn't sufficient time between the cessation of the rocket motors burn and the impact with the ground for the bomb to slow back down to terminal velocity then it will be travelling faster and therefore expend more energy upon impact.

However, if you increase the velocity to much then you would more than likely run into problems with the bomb breaking apart rather burying itself in the ground thus defeating the whole purpose of the weapon.

I suspect that in the case of the bomb we are discussing the limiting factor is maintaining the integrity of the explosive head and detonation mechanism after impact and during the ground penetration phase of the deployment of the weapon. If that is the case then adding extra speed to the bomb in any way would render the weapon useless.

On the other hand if the bomb is released from a low altitude then using rocket motors to increase the bombs altitude so that it was sufficiently high to reach terminal velocity would be beneficial and ensure that the bomb had the kinetic energy to penetrate to its designed depth. However, you could also just use the rockets to boost the speed of the bomb as it falls towards its target which would probably be a simpler method of deploying it.

The question now becomes at what altitude the bomb will be released. If it were going to be from altitude the current B-2 spirit bombers would not be able to deploy the 15,880 kg device. This is not because it couldn't lift it as it can carry a bomb load of 23,000 kg, but this has to be spread over two separate bomb bays so you couldn't put the weapon in the B-2 without modifying the aircraft.

That leaves the B-52 and B-1B. The B-52 would have to deploy the weapon from as high as possible to avoid enemy ground fire, but even then it would still be a sitting duck to the more advanced surface to air missiles. If it were deployed from a B-52 then it would almost certainly reach terminal velocity before impacting the ground making additional altitude mute.

That leaves us with the B-1B Lancer. Now this aircraft could deploy it from either high or low altitude, but it is designed cruise at relatively low speed and high altitude until it reaches enemy territory then it makes a low level high speed dash for the target, releases its weapons and gets the hell out of enemy territory as fast as possible, then it gains altitude and slows down again to conserve fuel for the return flight.

Now having said all that my guess is that they would modify a couple of B-2 Spirit stealth bombers to carry a single 15,880 kg ground penetrating bomb that would be deployed from altitude. That way you keep the bomb simple by allowing it to gain it's penetrating energy from is fall from while keeping the enemy unaware that they are about to be attacked. All the other options would give the enemy some form of advanced warning of the attack that could vary from a couple of minutes with a B-1B to an hour or more with a high flying B-52.

There, is that enough science for you or do you want all the mathematics and calculations behind the comments?

It is my understanding it will fit within an unmodified Spirit bomb bay with a special rack. but it is one to a customer which means that a number of B-2's will be required for most missions.

Because the bomb bays on the B-2 Spirit are next to each other rather than in line as they are on the B1-B and B-52 I would have thought that would have made the aircraft out of balance and cause it to roll to one side. But that's just my opinion and they aren't that far apart so you may be able to get away with it.

Slowing the bomb down is probably easier than speeding it up.

So, releasing it at a high altitude could be compensated with some form of a drag chute that could either ride the whole trip down or be jettisoned at a specific stage of its downward trajectory.

I've seen the guidance package pictures and instead of using fins, it actually uses big paddles that look a little like the old Mk 82 Snake Eye retarded bombs from the Vietnam era... in fact Boeing had to recall the first production run to reinforce the paddles if I recall correctly

Thanks. I think I get your drift.

Is this what you are saying?

Your first paragraph asserts that for a fixed amount of mass, the only reason to assume additional altitude above that required for gravity to accelerate that mass to terminal velocity is to provide a larger window of target acquisition, ie more time to influence guidance?

However, if it did gain additional altitude over that required to attain terminal velocity, and it also contained propulsion that increased it's velocity by 20%, what would be the appropriate increase in mass be that would still provide a net positive to the energy expenditure sum. That is really clumsy, sorry. If you increase mass by 100lbs, and increase the altitude at which that mass is released, requiring an additional amount of energy to boost that larger mass to higher altitude, what is the required increase in speed of impact to offset the energy equivalent of the increased energy budget for the projectile launch?

And by the way, I don't have a clue, so I really appreciate the skill with which many of you approach and analyze these topics.

an instant good answer, thank you very much. I was assuming that in almost any conceivable configuration increased mass and velocity will deliver a more devastating buster. It's clear that it's a little more complicated than that. Love that FEA.

In my relentless efforts to prod, and after rereading your post at least three times, I realize that my question revolves around efficient use of energy, and not about building the best performing buster. I was trying to reconcile the energy required to boost the busters performance with increased mass and velocity (which is the question I inferred from the OP) with the additional energy required deploy a heavier faster buster.. I, like you did in your example, did not consider adding more explosive power to the buster at penetration, as many of the fine answers have.

Again, thanks.

Is that Penetrating an equal substance... "Cement" ? Earth gets More dense the deper the penetration, doesan't it? ( Compaction Multiplied.) You must have observed , that I didn't understand any of your math... [D- Hi School Grad!]