The kind of person who believes 2750 tonnes of ammonium nitrate stacked in bags on a warehouse floor blasted a 43-meter deep crater in Beirut is the kind of person who believes two jetliners caused the Twin Towers to "collapse" & destroyed the rest of WTC on 9/11!
NYTimes reports 2750 tons (tonnes?) of ammonium nitrate was "roughly equivalent to 1,155 tons of TNT" (assumes RE factor 0.42). Let's assume all that NH4NO3 could somehow be made to burst like a high explosive bomb. How deep a crater would you expect?
Well no need to imagine. We actually have a quite similar precedent in Sugar! In Nov 1951 as part of Operation Jangle a fission Mk-6 bomb was detonated on the surface of desert alluvia at NTS producing yield of 1.2 kt TNT. The test name (Sugar) was mnemonic code for "surface".
So how deep a crater did Jangle Sugar blast in desert alluvia? Would you believe only a depth of 17 ft (5.2 m) and diameter of 90 ft (27.4 m) - far less than the 43 m depth & 120-140 m diameter that #MSM is reporting for Beirut for the same size "bomb"!
Now the landfill in the Port of Beirut may not be identical to desert alluvium but US Army Engineers have studied cratering by explosions extensively & have found comparable numbers in all kinds of media.
So if a surface 1.2-kt explosion can only blast a 5-meter deep crater, how could you possibly blast a 43-meter deep crater like Beirut? Well you could do two things: 1) bury the explosive device deeper and/or 2) increase its explosive energy (TNT equivalence).
When the US Army Engineers buried the same 1.2-kt bomb 17 feet below the ground (DOB=17 ft) w/Jangle Uncle (mnemonic code for "Underground"), the crater depth increased from 17 ft to 53 ft, going from "Surface Burst" to "Shallow DOB" (see figure)
With Teapot Ess (March 1955) the US Army Engineers buried the 1.2-kt device even deeper (DOB = 67 ft) and blasted a 90-ft deep crater as they approached “Optimum DOB” (biggest possible crater with that device)
To go beyond "Optimum DOB" ~ 67 ft, the 1.2-kt device no longer blasts a conventional crater (below). Thus there is NO WAY a 1.2-kt device can actually blast a 43-m (141-ft) deep crater, at least in desert alluvium. The Beirut crater would have required a bigger explosion.
So how big an explosion would it take to blast 43-m deep Beirut crater? Well depends on how deep you want to bury the device. How about burying 100-kt device 635 feet beneath the surface? WAAAY TOO BIG A CRATER! That's Storax Sedan (July 1962) w/crater depth 323 ft (98.4 m)!
Fortunately US Army Engineers have made the job easy by compiling all depth results of cratering tests in the NTS desert alluvium & similar media in this declassfied Figure 4.3 from a heavily redacted study that I encourage everyone to download now
Now most of you are going to roll your eyes at Fig 4.3 but it is not really hard to use. It's like all those x-y coordinate graphs you loved so much in high school! You can do the scaling conversions on your computer's search bar! A straight edge is helpful for interpolation.
Fig 4.3 shows that the plot of "Scaled Crater Depth" (ft/kt^(1/3/4)) vs "Scaled Height/Depth of Burst" produces a nice smooth curve at all depths & yields in similar media. So given 2 of 3 parameters (yield, apparent crater depth, HOB/DOB) it is easy to calculate the third!
According to Fig. 4.3, the smallest blast that could produce a 43-m (141-ft) deep crater is ~5 kt @ DOB=131.5 ft.
As the blast increases, DOB decreases.
For a true surface explosion (DOB=0) it would take a blast of 765kt!
Even 5 kt precludes any consideration this explosion could be of chemical origin. The largest planned conventional explosion on record - Minor Scale (June 1985) - w/4744 tons ANFO (4.2 kt TNT equiv) required a hemisphere 44 ft in radius. Now imagine that at DOB=131.5 ft!
At this point in discussion of nuclear terrorism somebody always asks "If it's a nuke, where's the flash? Where's the RADIOACTIVITY??" For starters underground nukes simply don't have as bright a flash as aboveground nukes. Compare Teapot ESS (left) & Jangle Sugar (right).
As for the more difficult topic of radioactivity, let me paraphrase physicist Heinz Pommer re 9/11: "Radioactivity can hide more easily than craters!" I tend to trust empirical evidence on cratering & laws of physics more than I trust #MSM reports about radioactivity!
Re radiation effects, unfortunately we have also been conditioned since the start of the Cold War to believe that detonation of ANY nuclear bomb would be as catastrophic as the above-ground, very dirty gun-type U-235 fission #LittleBoy bomb used at Hiroshima.
Nuclear weapons have gone through tremendous "advances" since that Hiroshima bomb. They range in size from the 50-megaton Tsar Bomba weighing 60,000 lbs to the 10-ton Mk-54 weighing only 50 lbs!
Following the 1st generation of fission bombs, by 1952 a 2nd generation of fission-fussion bombs developed, bigger & deadlier in terms of energy but relatively “clean” compared to fission bombs in terms of nuclear fallout. (Diagram courtesy of Heinz Pommer)
In 1960s & 1970s US & USSR had programs promoting “peaceful nuclear explosions” (PNE). In US called Project Plowshare included plans for major earth-moving projects for using cratering blasts w/hydrogen bombs for mountain passes, harbors, canals, etc.
Both US & USSR continued to refine 2nd generation devices to produce very high % of “their yield via fusion-only reactions, and therefore created orders of magnitude small amounts of long-lived fission products as a result”. In US mainly carried out at Lawrence Livermore.
Richard M. Lessler noted in 1970 “Although it is theoretically possible to have no radioactivity produced by nuclear explosives, this goal has not been achieved" but LLNL had made or suggested modifications to minimize production of radionuclides
NYTimes in 1978 reported US scientists had started work on a “reduced residual radiation” (RRR) bomb aka "blast bomb" that “dramatically reduces fallout”, what Andre Gsponer of Independent Scientific Research Institute called a 3rd generation nuke
“The blast bomb would be detonated at gnd level, sending enormous amts of debris into the air. Its tactical mission on the battlefield might be to DIG HUGE CRATERS, DEMOLISH BUILDINGS or bury mtn passes under debris” but “MINIMIZE RESIDUAL RADIATION”
Washington Post reported "a blast planned to explode ON or UNDER the ground, throwing enormous amounts of debris" & quoted govt nuclear weapons expert "This is the original idea of a 'clean bomb'...designed to create a minimum amt of fallout"
AP 5/78 Am nuclear scientists "still years away fm producing a “clean” tactical nuclear bomb but...have gone a long way toward mastering the key process wch would result in total combustion of nuclear materials in an explosion", only “prompt radiation” wch disappears quickly
July 1985 NYTimes reported that, according to a laboratory brochure, weapon scientists at LLNL back in the 1970s had successfully DEVELOPED a "Reduced Residual Radiation Bomb," i.e., "a tactical warhead that 'dramatically reduces fallout"!
After 1985, any mention of RRR disappears but curiously in Jan 2001 US DOE, using a brand new term "Minimum Residual Radiation (MRR) Weapons", acknowledged "The fact of successful development of MRR devices" & continuing weapon lab interest in MRR
Could the Beirut nuke have been one of these MRRs? Unfortunately info abt MRRs is highly classified. However, one clue that MRRs are a good candidate is, as reported in 1978, RRRs were designed to replace the US stockpile of Atomic Demolition Munitions (ADMs)
The US arsenal had two types of ADMs: Special ADMs (SADMs) and Medium ADMs (MADMs). The smaller SADMs used the Mk-54 warhead package w/variable yields (10 T–1 kT) weighed 59 lbs (Mk-54 only) or 150 lbs (complete) and were 16 in diameter by 24 in long.
MADMs used W-45 warhead w/variable yields (1 kT-15kT) weighed 150 lbs (W-45 only) or 350 lbs (complete), 11.5 in diameter & 27 in long. MADMs (top left) thus had a potential blast yield (15 kT) as powerful as the Little Boy bomb that destroyed Hiroshima (all other photos)!
ADMs were in the news in 1978 b/c W Germany did not like that US "Zebra Package" had 141 ADMS ready to go in prepared shafts in the Fulda Gap & Kinzigtal to stop the enemy at bottlenecks (bridges, highways, tunnels) in case the Warsaw Pact invaded
Despite criticisms, US Army said both SADMs & MADMs needed. But some officers complained “Under present plans, ADMs are supposed to be exploded in deep holes to dig the biggest possible crater & to minimize radioactive fallout.” They wanted an anti-personnel radiation weapon!
In 1984 ADMs were still in the news. Jack Anderson reported “As of early 1983, according to a secret Pentagon report, the US had a total of 608 ADMs – 372 in Europe (mostly in W Germany), 21 in the Pacific (mostly in S Korea) and the rest stored in this country.”
Anderson: "Designed to be buried underground, the ADMs’ three chief effects are cratering, blast & ground shock." Qtes Army manual “Cratering is used to destroy massive targets, such as large bridges & dams, and to create obstacles by excavating a great volume of material"
Anderson: "Because friendly troops would be operating in the area of ADM demolition, the weapons are designed to as “clean” as possible, giving off minimal but still deadly radiation."
Anderson 1984 reported "the ADM will be phased out over the next few years as Pershing & cruise missiles take over a larger responsibility for NATO’s defense. ADMs will remain in S Korea, however. Some have already been deployed underground near – & possibly under – the DMZ."
In Apr 1985 a curious report that, even tho NATO had agreed to remove all ADMs from Europe, DOD was developing a "nuclear backpack" nicknamed ADAM, standing for Advanced Atomic Mine. Since ADAM was going to do everything SADM already did, was ADAM really an RRR blast bomb??
So let's recap:
ADMs ranging in yield fm 10 tons to Hiroshima-size 15 kT designed 1960s to be buried in deep holes w/three chief effects - cratering (“dig the biggest possible crater”), blast & ground shock – while minimizing radioactive fallout. Does that sound like Beirut?
Lawrence Livermore in 1970s developed 3rd-generation “Reduced Residual Radiation Bomb” (RRR) aka "blast bomb" that “dramatically reduces fallout” to replace US stockpile of ADMs which are phased out in 1980s. Sounds even more like Beirut!
2001 US DOE announces "successful development" of "Minimum Residual Radiation (MRR) Weapons". I suggest MRR weapons are 3rd-generation ADMs that had achieved goal of “total combustion of nuclear material in an explosion” apart from “prompt radiation” which disappears quickly.
If US had such weapons in 2001, then undoubtedly they still have them today. And if US has them, then quite likely other nuclear powers have them. Since the Beirut crater suggests a 5+ kT underground nuke, the perpetrators would have needed the MRR equivalent of the MADM.
How dastardly if the perps used a 15 kT MRR in Beirut in “honor” of 75th Hiroshima anniv! Buried 69 ft below surface it could have blasted the 43-m deep crater. And if the perps used an MRR in Beirut, what are the odds they have used them before – and will use them again?
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