Design and Installation of Retrofit Packages

• Equipment Supply:The most important activity in this area is the design and supply of vehicle repower and retrofit packages.  Beginning in 1968 with an M35 Series of 2½-ton truck package and in 1975 when work began on the development of tracked vehicle repower packages, NAPCO has produced and sold over 2,000 truck packages and 1,300 packages for tracked vehicles.
  
• Systems Integration: A professional team of systems engineers works to plan, engineer, install and commission integrated vehicle systems that are tailored to meet specific operational requirements.
  
• Logistics Support: To perform this service the company has a staff of sourcing specialists who have access to an on-line computerized data file, a technical library encompassing the whole range of US Military Vehicle Technical Manuals and files of US commercial equipment.

• Increased Performance: Clearly the most often cited reason for undertaking a retrofit.  Performance is an area where choices abound that are not often well understood by buyer or seller.  Most often what is implied is an improvement in performance while that is simply one of three choices which the designer can produce.  The expected result is, of course, a substantial increase in performance.  The danger is that the enhanced performance of the replaced component could overpower the original equipment.  Higher horsepower could brake transmissions, final drives and suspension components in trucks and tanks.  Other possible dangers include turret controls or fire control systems rendered ineffective by the accumulated wear in the original equipment turret ring gears and bearings.  Performance equaling that of the original machine is often the necessary course.  Unfortunately, it is sometimes harder to explain to a buyer of this when the actual advantages then are improved maintenance and operational reliability.  Finally, the system can be optimized for a particular set of conditions, such as, for example grade ability instead of speed in mountainous country, or fuel or cooling capacity in northern Europe and so on.
  
• Reduced Maintenance:  This area is a key factor for automotive retrofits while it may be totally unimportant for retrofits of turret and electronics systems.  The automotive subsystem is one of the few parts of the vehicle that actually is used and wears down as a result of that use.  While the vehicles are used and gradually age their reliability begins to suffer.  Subsequent overhauls become more and more expensive due to the inevitable increase in spare parts prices and the generally declining availability of spares for vehicles manufactured years and sometimes decades ago.  It is also possible for the retrofit designer to pick from components with good records of steady spare part availability.  Adopting a military version of a widely used commercial engine: may mean that spares and maintenance expertise already are available.  At the same time the designer can introduce improvements that would reduce the maintenance burden outright.  Using a power pack design to allow "ground hop" capability in a M4 Sherman tank retrofit is one example of an improvement of this type.  Depending on budgets and technical capability, it might also be desirable to include built-in test equipment, although the designer has to be aware of what will be technologically appropriate for the operator.
• No need to "cannibalize":   As a last resort, it is possible, for a time, to keep aging vehicles running by removing good parts from other vehicles and using them to repair the remaining vehicles.  Retrofit solves this problem in two ways.  First, the retrofitter should replace those systems that have had to be supported in this fashion.  Second, working with a vendor that has an engineering capability should give the operator of the vehicle access to solutions for those hard-to-find parts that are not otherwise replaced.
• Reduced need for new vehicle purchases:  This is the final and basically only criteria.  Reducing or eliminating the need for the huge capital expenditures for new equipment is one of the key reasons to justify a retrofit.  The case may be made that the performance of the new can be realized with the retrofitted old-trucks. it may also mean that acquiring greater quantity available for the same budget will justify accepting a less capable retrofitted vehicle in place of the new that can only be afforded if low quantities are purchased.  It may also be argued that the retrofitted vehicles will adequately meet the threat and thus new vehicles cannot be justified.