Imagine that you are a fire chief, and your team is on the 13th floor of a 26 floor high-rise building that’s on fire – in the middle of night. You send three of your firefighters in a state police helicopter to rappel onto the top of the building so they can advise those trapped inside the building to stay put. They also must try to open up the stairways to let the smoke out. As smoke envelops the site, it is extremely difficult to see. But you know there are two air conditioning units and a six foot antenna – and you hope they can find something safely to land on.