SD-8G sounds like a new TV spinoff, about a portal into an alien world, but it's Security Directive 1542-04-08G, an insight into the way the TSA thinks about airports. As of June 1st, 2009 the TSA declared that everyone having unescorted access to the airside at any airport with airline service must undergo background checks for a badge, on a per-airport basis. That would be almost like requiring drivers to have a separate permit for every highway exit they use that is also used by transport trucks. It's so ridiculously infeasible that the Security Directive 1542-04-08F containing that provision did not go into effect, and, thanks to the input of pilot advocacy groups, was watered down to SD-8G which at least allows us to land, pee, and fuel our airplanes.
The new requirements, which have officially gone into effect (but might not be enforced everywhere), tell transient pilots without airport badges to remain close to their aircraft and leave its 'footprint' only for trips to and from the FBO. They haven't yet defined clearly our movements at airports with self-serve fuel, or even exactly which airports count as having airline service. (Does the "airline" have to fly something bigger than a Beaver? Does the "schedule" have to be daily? Do they have to be passenger airlines?)
They say pilots are advised to call ahead to airports they think might have airline service and assure themselves they are in compliance with the new TSA directive. Whom should we call? Are they going to publish TSA 24-hour numbers for us? I don't expect this to really interfere with my movements when I'm south of the border. American FBOs are pretty proactive, so if there is one I'll ask them what the TSA expects of me before I get out of my airplane. Any wandering around I do on the apron is usually in search of FBO personnel, anyway.
TSA hasn't interfered with safety publications yet, at least I've never seen a notation saying "pilots without badges are not permitted to park on apron C". It might be feasible to designate airports by security class, and publish those in the AF/D where pilots know what they are dealing with. Have a few where pilots require A-class badges, with the same background checks required by airline pilots, but allow a pilot to do one A-class security check and then hold a badge valid for JFK, DCA, LAX, etc. If he's at an A-class security airport with no badge or a lower class badge, he needs an escort. B-class airports would have a painted line on the apron around the area where airliners parked and you'd need an A or B-class badge to be inside the line. And so on down to grass fields in Montana with no fence around them and no stinking badges needed. What do they gain by per-airport clearance? Is there really something in my background that could make me safe to walk across the ramp and borrow a Dustbuster in Albuquerque but a threat to national security if I move away from a hangar to get better cell coverage in Spokane?
The thing that really drives security crazy is that they can put up a big fence and lots of rules but they can't control access to the airport. Despite all the barricades, signs and security checkpoints, any old Canadian can still literally fly in over the fence. For any spot on the field, if an airliner can get there, I can get there, too.
If you are a pilot, or even just hope to become one someday if time permits, or want to support the freedom to fly, I really suggest that you join COPA or AOPA. They have excellent publications and member services, but even if you never use those, they are an essential presence in monitoring and countering the regulations and fees that officaldom concoct while wearing airline-shaped blinders.