The current Avweb article indicates that the proposed rule would supersede an existing rule which specified zero tolerance for non-aviation hangar use. EAA therfore calls the proposed rule an improvement. Clearly the old rule was very rarely enforced and apparently little known since there hasn't been any uproar like this current one. Is there anything indicating the new rule is going to be enforced any more than the old one?
That's part of my concern. The proposed rule might be better than the previous one, but now we're drawing a lot of attention to it, and it might make things worse for a lot of people.
My other concern is that, like Paul said, whatever gets put into the rules is what we're stuck with. And my reading of the rule says there's still too much room for interpretation, too much leeway for the FAA or an anti-experimental airport administrator to impose draconian policies, and not enough protection for homebuilders and aircraft owners.
"Final assembly" might mean that you have your airworthiness and only need to put all the fairings back on. Or it might mean you have 30 days from moving in to getting the airworthiness certificate. Yes, the latter has been the plan for my -7 all along due to a lack of conveniently-located airports (I grew up spoiled in that regard), but I don't believe that should have to be everyone's plan. It also rankles me that building an airplane isn't considered by the FAA to be an aviation-related activity--though I wonder if that could be turned around on them to force them out of some of the microscope-level oversight of every step of certified aircraft production?
The note about "temporary storage" for maintenance/restoration isn't clear enough, either. For example, a 30-day limit (which I could see someone trying to impose) would impact condition inspections, panel upgrades, engine overhauls, annuals (for owners of certified airplanes), major repairs, etc. There's also not enough protection for doing maintenance in the hangar. In my mind, there's an absolute right for aircraft owners to perform maintenance on their aircraft within the limits of the law (which I believe should be broader) and the bounds of safety/fire prevention. This ought to be codified.
Finally, I'm concerned about the "incidental items" protections, especially the "insignificant amount of hangar space" line. Once again, there's a lot of room in there for someone in power to clamp down on anything past a desk, chair, and towbar. This one hits home, since I was fortunate enough to spend my teens and early 20s around a certain large group of RV builders/owners. At the time, they had a large hangar with several aircraft (including ours) parked in it, some being built and some having flown for years. They also had a snack/rest area, community workbenches and part storage, a couple of old bikes, and a bunch of tables and chairs that were used to host various cookouts and other events. A lot of this extra "stuff" would probably be considered "non-aviation related", and took up more than "an insigificant amount of hangar space", though it never crowded out an airplane. But I'd say that the atmosphere fostered by this hangar and all its contents ("aviation-related" or not), where someone was usually around if you needed another set of hands, where young bucks like me could fly with and learn from guys who probably had more time in the air than I had on my own two feet, where everybody was welcomed instead of getting a cold shoulder, probably brought more business and more flying to that airport than any amount of bureaucratic rule-following or draconian, antiseptic, 5S-style hangar contents restrictions.
Yes, if someone is storing imported widgets in the hangar or running office space there instead of housing airplanes, by all means, kick them out if airplanes or airplane projects are waiting. And I generally understand if someone with an actively flying airplane is waiting on a hangar occupied by a homebuilt project that hasn't been touched in a year or two. But if there's enough demand for hangars from legitimate aviation-related activities (to include building!) then the solution should be to build more hangars, if there is any room to do so.