In prototype shops of Aircraft Industry minimizing the lead time is very important than minimizing the cost because long lead times requires planning, ahead of plant in all departments like personnel, equipment, material, purchase several months in advance of actual order in hand. As the longer lead time can cause to affect on accuracy of such plant. In prototype aircraft environment every downstream department activity needs the input from upstream department. And if it occur any kind of bottleneck in upstream department, the downstream department decides to go for another job which does not require the upstream input. And the scheduled job will be completed in a week or month rather than prescheduled date. The Q.R.M. redesigns the organization structure which works on the traditional methods of manufacturing or mindset, which works itself against the principles derived. And it suggests the new methods of manufacturing or principles such that the lead time can be controlled in order to control the cost as a consequence of it automatically.