If an Airworthiness Directive is published for your aircraft which makes it illegal to operate until complied, and your aircraft is sitting in the Alaskan wilderness with the closest facility hours away, what is the correct procedure? Would it be against the law to fly it directly to the facility? Would a technician have to travel to you? Any bush pilots have an answer? Thanks.
What to do when an AD is published but your aircraft is nowhere near a maintenance facility?
First thing you would do is study the compliance requirements of the AD.
Most ADs come with some kind of "fly-by" compliance period either by calendar date or hours/cycles. It's pretty unusual for an entire type or model to be grounded immediately.
But if that happened, you would examine the compliance procedure. If a mechanic is available to be flown to the location with the equipment necessary to perform the compliance procedure, you might decide it's cheapest and easiest to do that.
For example, if a fleet was grounded as of midnight this AM, and it required a detailed visual inspection, or even a Non Destructive Test of something like a control horn or some such that allowed some field performable procedure like Dye Penetrant, I might just have the mechanic flown to the site, do the procedure called for in the AD, sign off the inspection, and we're back in business.
If a mechanic wasn't available, or the compliance requirement needed the airplane to be flown back to a maintenance base, you would contact the FSDO for your region to apply for a ferry permit to take the plane to a maintenance base. The terms of the ferry permit will determine whether or not some check has to be done before flight, or whether a mechanic has to do it or just the pilot.
Immediate grounding ADs are generally avoided because they are so disruptive and result in a flood of ferry permit applications. Normally an analysis and risk assessment is performed to arrive at a compliance grace period that meets a mathematical risk probability threshold while giving the fleet as much flexibility as possible.