http://www.army-technology.com/projects/mrav/ The Boxer MRAV uses 'Mission modules, which fit into the base vehicle, provide static battlefield installations to suit the nation specific requirements, including headquarters, medical units and logistic centres. The modules incorporate a primary safety cell with a triple floor. The base vehicle operates independently from the modules. The units are air transportable. The modules are interchangeable in less than one hour.' Has this use of mission modules been tried before and are there penalties in this system?
I can't think of any previous modular vehicles off the top of my head. Penalties: yes. Weight/ space. Since each module has to be strong enough to not collapse when removed from the vehicle then it has to have enough structural strength to support itself, rather being part of the vehicle. (As the quote says - they have their own floor). If the modules were part of the vehicle (e.g. family on a common chassis) then overall integrity (structural and NBC sealing) would be easier, and that would reduce weight. (Or improve armour for the same weight). Since there is more than one floor the internal space will be reduced for a given vehicle size, or a larger vehicle for a given internal space. I suppose that it's a way of getting multiple vehicles for a set budget - buy X no. of chassis and a selection of modules and then configure the vehicle with the requisite module for a given mission. Cheaper overall than making sure you have enough APCs AND radio vehicles AND MICVs AND whatever else they have modules for, as separate vehicles...