Surely this thread should now be RPGs vs Tanks?
FAE/Thermobaric/Novel Explosive (NE) warheads work by a combination of high blast overpressure & residual vacuum effects, with secondary incendiary effect. Results are virtually the same as a Boiling Liquid Expanding Vapour Explosion (BLEVE). [This may just be semantics in action]
The dual effects of a rapidly expanding oxidising fuel front overpressure, with consumed atmospheric oxygen producing a residual vacuum produces major damage to personnel and non-hardened structures.
The fuel (liquid or powder) is dispersed like an aerosol by a bursting charge, before an igniter system sets off the cloud after a precise delay to allow full combustion. The Fuel-Air mix has to be at the optimum level to prevent either:
a} A 'dud' with dispersion of unburnt fuel or
b} A localised fireball with minimal blast effects
A correct ignition can produce very little flame, if this video is actally a RPO-A test:
http://www.warfare.ru/?linkid=1847&catid=278&video=true
This was initially the technical blocker with these munitions. Chechen reports of Russian chemical weapons use have been attributed to incomplete combustion of TOS-1 Buratino 220mm rounds.
http://www.globalsecurity.org/milita...ssia/tos-1.htm
Fuel cloud flows, and thus blast/vacuum effects are non-linear allowing for bunker and cave attack successes. This is in comparison to HEAT and HE where local objects may cause blast 'shadows'. The fuel will flow around corners & blast walls, down foxholes and OPEN HATCHES and into shattered windows {the actual initial overpressure of the expanding fuel cloud can incapacitate before ignition), VENTS and EXHAUSTS/INTAKES.
The rapid combustion of the flammable 'gas' cloud causes blast type injuries, including internal organ trauma (lungs, liver...)ears, eyes etc. Secondary incendiary effects can also (from a victims point of view) be major.
A thermobaric weapon such as a RPO-A would be very likely to cause severe injuries to an 'unbuttoned' tank crew, with the vehicles optics, engine and any flammable impedimenta (Camo covers, tentage, external POL) all contributing to a high chance of, at least, a disabled vehicle.
The chance of the weapon hitting has been increased by 'Kornet-E' being available with a thermobaric round.
NBC overpressure systems are unlikely to be employed permanently by the crew to defeat FAE blast(though I doubt how effective they'd be for either this or nuclear blast in an unbuttoned vehicle).
A 'buttoned' MBT would probably save the crew, but the vehicle may be immobilised.
Given the problems of proper fuel-cloud formation, and precise ignition timing, I thought that ERA would prevent/defeat FAE ignition success. I was thus amazed to see thermobaric warheads being used as the #2 in tandem effect munitions.
Bazalt (Russia) has developed the RShG-1 and RShG-2 tandem charge RPGs, with a HEAT precursor and (optionally) a thermobaric instead of a HEAT secondary.
http://bazalt.ru/bl-boy-eng.htm
Talley Defense Systems(USA) have developed both the SMAW-NE and the LAW M72-NE. These are 'smart' warheads which sense whether the target is hard or soft to alter FAE initiation timings.
http://www.talleyds.com/products/brochures_videos.htm
The above weapons are primarily designed as 'bunker-busters', with capabilities against light armour.
The idea of a FAE being delivered INTO an AFV is frightening, as the enclosed, confined space would provide optimum kill conditions. Crew survival would be unlikely indeed.
Personally I feel that a 'triple' warhead [1.HEAT or displacer rod 2.HEAT 3.FAE package] would be needed to defeat ERA and deliver a warhead/effect into the AFV. Sadly for tankies I have seen specs on triple warheads, though not with FAE as the tertiary unit.
The 'bonus' of carrying a specialised munitions package THROUGH the armour of an AFV has enthralled designers and ordnance buyers for years.
The original rounds for the German PzB 38 & 39 Anti-tank rifles consisted of 1. Outer jacket, 2. Hardened steel penetrator. 3. Tear Gas Pellet to force crew to evacuate vehicle.
On the few occasions the round actually penetrated the vehicle, the tear-gas pellet was left outside the armour, affecting supporting German troops and preventing them from assaulting the (disabled?) AFV. These rounds were replaced by APCR (Armour Piercing Composite Rigid) type rounds with a tungsten penetrator filling in for #2 and 3 in late 1940.
APHE (Armour Piercing High Explosive rounds trade off penetration for HE effect on the 'protected' side of the armour. The number of unexploded, penetrated, APHE rounds defused after naval battles shows that the reliability of such rounds is lower. The penetration values of such rounds are also less, although I can see why they are becomong the standard load for Autocannon.
I have no doubt that both defence industries and armies world-wide will enjoy the expensive search for the "Magic Bullet".
Andy Weaver