dr. gilmore, you have a very important job. you're the director of operation, test and evaluation at dod. and you've talked about the plane today. modeling and simulation are very important as far as not just planes, but anything else that comes along. but is there any real substitute once you pass that for testing? and evaluation? why don't you get into that. >> senator, we use modeling and simulation in numerous operational testing activities because we have no choice. in the particular case of joint strike fighter, we are -- it's currently under development. it's an analog to what is currently called the air combat simulator down in marietta, and it is being used for all the follow-on development that's being done to improve the capabilities of the f-22 where you have a full-up effects base simulation of the aircraft, and you can take operational pilots into the simulator and have them fly the aircraft as realistically as you can in a simulator. we're going to be doing the same thing with the joint strike fighter. however, t

dr. gilmore how would you address the fly before you buy verses concurrence a? >> there is always going to be a certain amount in the program this was an extreme case that i think he accurately characterized as malpractice but what caused this to happen again site have a different perspective i think is simple. the department has a long history of the seating himself about the cost scheduling difficulties and in this particular case there was the number of assumptions made that there is high commonality in the structural parts among the various aircraft that not surprisingly overtime and i was there when the program started and indicating warnings at the time that you are making unrealistic assumptions of commonality to drive the unit cost down in your analysis because at that point* everything was on paper by analysis and it turned to be unrealistic but those kinds of assumptions that carry over when it decides to start production without a flight test that the simulation modeling of fusion capabilities and how the censors would respond would be so explicit the