How old is she? And why would you have to put a diaper on her to walk her? I'm confused, lol. I know she's in heat but if you're outside, it shouldn't matter. I used to own female dogs and they never made a mess or anything. Also, is there a particular reason you're not getting her spayed? I find spayed dogs are not as aggressive. I agree with exercise, exercise, exercise! A tired dog is a happy dog.
She just sounds like she's trying to be protector of all things "evil" like that noisy helicopter, lol
Let her know she doesn't need to protect you - you're going to protect her. Overall, I do believe energy is a huge part of it. You're sounding really stressed out and angry at her right now (understandable!) but I think if you calmly correct her, things will work out better. Jackson's never been a terrible barker or anything but occasionally when he's gone into his fits, I remember getting soooo angry because it was always at the worst time, I would jump up, pissed off, shake the can, and it NEVER worked. Once I calmly went over to him, gently told him "Thank you" for the warning that there's a bird outside (or whatever he was barking at) he will stop. Or I simply go over to him, snap my finger and say "Quiet" one time. Have you tried a squirt bottle? Whenever Jackson barks at my dad's cats, he gets a quick squirt in his face, now 99% of the time he won't bark at them.