The trade of aeronautical engineering is a tricky one that requires careful planning. The balance between the design's power and cost is extremely important. Engineers also need to ensure that all the bugs are worked out of the designs. A small bug can cost millions of dollars to retool and replace parts. Take the example of the F-22 Raptor, it was designed to be the most powerful jet fighter in the world. The design cost billions of dollars to perfect and, even with all the money spent on research and development, it still had problems when it was put into action. There were several cases reported of pilots experiencing hypoxia, due to a problem with the oxygen system.
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