The actual answer is, "it depends". The pads can be replaced very easily. Just pull the two AN4 bolts holding he pads onto the caliper and slide the caliper away from the wheel to get the inboard plate off (the outboard plate is released by the two bolts. Replace the linings and reinstall as they came off.
The "it depends" comes when the piston in the caliper is really dirty and extended way out because of worn pads. Very often the o-ring will start to leak when you push the piston back in, in which case you need to remove the caliper, remove the piston from the caliper, clean it and replace the o-ring. Then, of course, you will need to re bleed the brakes. It really depends mainly on how worn your pads are and somewhat on how dirty the piston has gotten(it doesn't hurt to carefully clean the revealed portion of the piston while the pads are off.
So, if you are depending on the plane for a flight soon after changing the pads/linings, make sure you have a set of o-rings and the brake bleeder and fluid available before starting the job.