Thermobaric war­heads put the power to demol­ish build­ings into the hands of the aver­age U.S. marine. But Americans arent the only ones with the weapons. The Chinese, the Russians — even guerilla groups — now have ther­mo­bar­ics’ shock­ingly destruc­tive power in their grasps.
Thermobarics aren’t just a more pow­er­ful ver­sion of nor­mal high explo­sive. The term encom­passes a range of dif­fer­ent types of war­head from fuel-​​air explo­sives, which release a cloud of flam­ma­ble mate­r­ial and det­o­nate it, to met­al­lized explo­sives whose expand­ing fire­ball takes in oxy­gen from the air. What they have in com­mon is that they pro­duce blast which has a lower over­pres­sure but a longer dura­tion than nor­mal con­densed explo­sives. In effect it is a shove rather than a punch: a ther­mo­baric explo­sion does not smash a hole in a wall, it pushes the wall over. An instan­ta­neous explo­sive over­pres­sure of 50 psi [pounds per square inch] is needed to kill. But one sus­tained for a frac­tion of a sec­ond at 10 psi is also lethal. Thats how ther­mo­bar­ics kill.
The basic idea goes way back, and any­one inter­ested in the back­ground — includ­ing a bizarre German WWII weapon, how a 500lb of coal dust can break win­dows five miles away and what new ultra-​​fine nanoex­plo­sives can do — should put my book Weapons Grade on their Christmas list.
But the ther­mo­baric threat isnt con­fined to his­tory books. In Iraq and Afghanistan, many US lives have been saved by the pro­tec­tion afforded by armored patrol vehi­cles, body armor and prompt med­ical atten­tion. Thermobarics may change that. Armored vehi­cles are safe only when but­toned up, as the blast from a ther­mo­baric war­head will ‘flow’ through hatches or other open­ings.
A detailed analy­sis points out that “con­ven­tional coun­ter­mea­sures such as bar­ri­ers (sand­bags) and per­son­nel amour are not effec­tive against ther­mo­baric weaponry.“
Other research indi­cates that cur­rent bal­lis­tic body armor actu­ally increases the sever­ity of blast injuries. Similarly, cur­rent com­bat med­i­cine is not geared to deal with the dam­age to lungs and intestines which are typ­i­cal of ther­mo­bar­ics — “diag­no­sis and treat­ment of blast injuries may require com­puted tomog­ra­phy, which might not be read­ily avail­able in the bat­tle­field.“
In 1988, the Russians were the first to field a shoulder-​​launched ther­mo­baric weapon, the RPO-​​A. It is also known as Shmel or Schmel from the Russian for Bumblebee.
As with the Marines ther­mo­baric SMAW-​​NE weapon, the Shmel is quite capa­ble of destroy­ing build­ings as this video shows. The Shmel com­ple­mented a wide range of other ther­mo­baric weapons includ­ing bombs, rock­ets and artillery in the Russian arse­nal. Controversially, secu­rity forces used the Shmel in the school siege at Beslan, a ques­tion­able choice for a hostage sit­u­a­tion.
New Russian devel­op­ments include a com­pact multi-​​shot ther­mo­baric grenade launcher for urban com­bat and a ther­mo­baric war­head for the RPG-​​7 used by guer­rilla forces world­wide. Similar prod­ucts are offered for export by the Bulgarians and other Eastern European nations.
Rumors of a Chinese licensed copy of the Shmel appear to be con­firmed with the emer­gence of this clone — it has the same cal­i­bre, same appear­ance and described as “fuel air blast­ing explo­sive”. Its effec­tive­ness against build­ings, bunkers is noted, as well as the fact that because the blast takes oxy­gen from the air, “per­son­nel in the air­tight space suf­fo­cates because of the oxy­gen deficit.“
Are such weapons in the hands of insur­gents and ter­ror­ists? During the Chechen con­flict, there were per­sis­tent sto­ries that Chechen sep­a­ratists had them:
“The Russian force, to explain exten­sive dam­age to build­ings in Grozny, stated that the Chechens had cap­tured a box­car full of Shmel weapons and were now using them indis­crim­i­nately,” one report noted. Newspapers reported that the weapons were recov­ered from Chechen arms caches
However, accord­ing to Tourpal-​​Ali Kaimov, a Chechen com­man­der inter­viewed by the USMC only a hand­ful of Shmel were captured.

The Russian claim that the Chechens cap­tured a ‘box car’ load of these weapons was part of a Russian dis­in­for­ma­tion cam­paign. The indis­crim­i­nate use of these weapons com­bined with its destruc­tive capa­bil­i­ties pro­duced a lot of col­lat­eral dam­age and deaths/​injuries among non-​​combatants. The Russian claim was a ruse in order to place at least part of the blame on Chechen use of the Schmel.

There is at least one doc­u­mented instance of an irreg­u­lar force receiv­ing Shmel: the Cobra mili­tia in the Republic of Congo reported in 2003.

Among these ship­ments were sig­nif­i­cant quan­ti­ties of the RPO-​​A ‘Shmel’, an extremely lethal hand-​​held launcher whose pro­jec­tile uses fuel-​​air explo­sive… This is the first time this weapon has been seen in the pos­ses­sion of a non-​​state actor.

The report, by the Swiss-​​based Small Arms Survey group, does not iden­tify the source of the weapon, but does pro­vides pho­to­graphic evi­dence.
So far, insur­gents in Iraq havent got­ten their hands on ther­mo­baric weapons. And reports from Afghanistan describ­ing ther­mo­baric vic­tims as being found dead with­out a mark on them have been over­stated — and alle­ga­tions about ‘dis­placed eye­balls’ — are highly doubt­ful. But it would seem only a mat­ter of time until these weapons make them into the worlds most intense con­flicts.
Some atten­tion has been paid to the threat posed by ther­mo­bar­ics, but lit­tle has been made pub­lic. In a series of com­puter sim­u­la­tions called Project Albert, the Marine Corps Warfighting Laboratory has eval­u­ated the effect of arm­ing pla­toons of attack­ers and defend­ers with enhanced blast weapons in urban assault. The results are sig­nif­i­cant — when the attack­ers alone are armed with them, they are much more suc­cess­ful, but when both sides have them the advan­tage shifts towards the defend­ers.
This may be impor­tant for the future of war­fare in cities. The spread of these weapons will make such actions more destruc­tive, and it will make infantry assault even more costly in terms of lives.
Agreement on an inter­na­tional ban on the man­u­fac­ture and export of such weapons might have been pos­si­ble some years ago, but now the genie is well and truly out of the bot­tle. Now it is a mat­ter of prepar­ing our­selves with bet­ter tac­ti­cal aware­ness of what such weapons can do, and improv­ing the med­ical facil­i­ties for deal­ing with ther­mo­baric casu­al­ties.
– David Hambling