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Besides the pre-made designs, will there be any individual motors available? If not can we have the cost of the motors and their specifications from the premade designs?
Robert,
You are free to "replace" the engines that come included with the base aircraft options (platforms A through E). As these base options are considered commercially-off-the-shelf (COTS), the engines are included in the price and the cost cannot be removed. If you want to use an alternative powerplant/engine you will need to incorporate the additional cost into the total aircraft vehicle element cost.
-Dr. Terwilliger