Helicopters and planes are altogether difference beasts. A plane must move forward to operate, using the air beneath it to give it life. Many planes and do loops, can bank, can fly upside. They can do all kinds of crazy things. Helicopters get their lift from the rotating blades above them. They take of moving vertically rather than horizontally. They can hover in one place, move backward and even move laterally - all things that a plane cannot do. Helicopters also come with different risks, like the force of the air that the rotors push down onto the body, the vibration of the rotors itself, etc. Banking can also be dangerous because the rotors are flexible which can cause them to hit the tail or cause the mast to bump up against the body. Either one is likely to destroy the helicopter in a few seconds. Now, there is obviously a difference between doing a loop and flying upside down. When a helicopter does a loop, it does not change the rotors air flow direction because doing so would cause the rotors to push away from the body (pushing toward what is now down), causing the rotors to hit the tail. While it is difficult to do, some helicopters can make the loop but they do so through momentum rather than inverted flight.
I don't much mind the distinction, though, because it is just plain amazing to see one upside down. It was certainly the highlight of the Air and Water Show for me. Some people say that such a stunt is pointless, but those people are probably boring anyway.
*Chicago doesn't have beaches. I know the difference between a lake shore and a beach; all the imported sand in the world will not convince me otherwise. A lot of the so-called beach has cement under it and the stretches in between have big lumps of cement blocks and barricades. In case you haven't seen the ocean, it does not come lined with a cement edge. Also, you don't get too many dragonflies. There were so many out yesterday that some of Alex's pictures look like a jet having a dog fight with an enormous insect alien invasion. Also, no matter how enormous a great lake is, the piddly waves just don't cut it. My biggest complaint though is the lack of salt water. A lake just cannot substitute the ocean. It's a shore, not a beach. That's why it is just off of Lake Shore Drive.