The ASDA — Air Show Demonstration Area — is the full airspace volume covered by the CoW/A. Everything inside it during performance falls under Air Boss authority. At a Basic Air Show, non-participating aircraft cannot operate in the ASDA while the show is running. That’s a hard rule, not a judgment call.

And the Flying Display Area sits inside the ASDA?

Right. The FDA — sometimes called the aerobatic box — is the defined three-dimensional volume where aerobatic performance is actually authorized. Its boundaries are written into the CoW. Know them precisely, because before you authorize any act to enter the FDA, you must positively clear it.

What does “positively clear” mean in practice?

It means you’ve verified the FDA is free of aircraft, debris, or anything else that creates a conflict — visually and by radio. You’re not assuming it’s clear because nothing was reported. You confirm it.

The Air Boss also needs a direct, unobstructed sightline to the full FDA at all times.

That’s a non-negotiable position requirement. Show center is the reference point for crowd-line separation distances, and show line runs parallel to the crowd — typically along the runway centerline. Before the show opens, you confirm your sightline from the Air Boss position covers the entire FDA. Any obstruction is a safety issue that gets resolved before performance begins.

So if a temporary structure or parked aircraft cuts off part of your view, you deal with it pre-show, not during.

Exactly. Once aircraft are airborne is the wrong time to discover you can’t see the north end of the box.