They can be built in Kit form and supplied as an add on in the field. Our unts in the field are in desperate need of this type of protection.
I think the issue is that where the action is really happening, the tracked and wheeled vehicles cannot go. Almost all of the transport is being carried out by helis. Had force protection continued to be a problem, we would have seen the APCs with this type of protection already inducted. The Army still prefers to use open vehicles with some up-armouring on the sides but providing easy ingress/egress out of vehicles. Maybe in built up areas the M-113 with this type of protection would make sense, but most of the combat is happening in terrain where vehicular traffic is minimal.
Here are some salient points about the challenges in the theater where our troops are engaged. These points have been gleaned from a presentation that GoC, SSG conducted in Jordan:
* Artillery fire is less effective because of the contours of the land
* Attack options are predictable
* Use of helicopters gives away your intentions
* Land mines are not effective because they are displaced by earth tremors or melting snow
* Delays in evacuation of casualties
* Defensive positions can be swept away by avalanches
* Resupply and reinforcement in the heat of battle are extremely difficult
* Difficult to achieve surprise.
* Close-quarter battle is required
* Re-stocking is done by mules
<- No vehicular transport!!!!! (Blain)
* Troops' acclimatisation is very important, as is physical fitness and endurance
* Illness caused by altitude sicknesses
* Maps and aerial images tend to be deceptive
* Distance is measured in time, not in space, due to the terrain
* An invisible and faceless enemy. People met without incident in daytime may "take up arms and attack" at night
* Night landing by helicopters is very difficult in forested mountains or at high altitude
*Vehicle mobility restricted to roads
<- Roads probably run across less than 5% of FATA
* Large numbers of troops required to hold cleared areas.
* Operations require intensive focus on logistics.
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My point is that the Army is probably more concerned with the biggest bang for the buck. Up-armouring a vehicle which has been used very sparingly is probably not going to see serial work.