We went a few months back. My first trip there in years and the wife and 8yr olds first times to ever go. We spent less than 3 hours total at the park. The ship was the majority of that time, but below decks lost his (8yr old) interest fairly quickly. He loved crawling around all of the guns up top though. The Drumm takes about 30 minutes tops. Its small, neat, but just not a lot to see. The museum with the planes we went through very quickly. I doubt you will spend any more time than that with a 5 and 7 yr old.