I am not sure about the direct flash in the car photos. Handsome cars none the less.
The huge cylinder thingy with stairs is a phenomenal photo!!! The composition is right on. Excellent use of a long lens.
I would also like to mention that I have a fear of long lenses. Fear may be the wrong word. Lets just say I rarely use them. I love teasing my co workers about using theirs all the time. Anyway, have you asked to enter the grounds of the tanks? (I wish I could think of what they are called) They will almost certainly say no, but it may be worth a try.