From Frontier's website:
"The decal application is almost like one giant contact paper project. The image is printed on "transfers" that have the image on one side and a peel back adhesive on the other. The chemical structure is not really the same as contact paper, but the process is essentially the same. The decals last up to five years. Damage to the decals occurs due to wind erosion, repairs on the tail structure and sunlight. However the tails are regularly maintained."
Semper ubi sub ubi.