The AKC breed standard states that the correct coat color is either a black saddle, with a tan head, ears and legs; or a dark grizzle saddle (black mixed with gray and white). Grizzle that is a mix of red hair in the black, often on the area of back before the tail are often the best and harshest coats.
There are, however, examples of non-standard black-coated and “red” (tan) coated Airedales, (the solid colored Airedales are NOT able to be AKC registered, since they are deviations from breed standard and have yet to be proven ‘ purebred ‘Airedale Terriers.) There are also the short coated “Redline” type Airedales, they appear to be genetic throwbacks in looks to the Airedale’s early days when the breed’s coats were much shorter than today’s Airedale. Even with their shorter coat they still have the same hard wiry outer coat with a soft under coat and fall well within the criteria of the breed standard and therefore can be AKC registered and most are registered.