3. The provisions relating to benefit (other than industrial injuries benefit) of the Act and of the regulations made thereunder shall, so far as they are not inconsistent with the provisions of these regulations, apply to an airman with this modification, that where an airman is, on account of his being outside the United Kingdom by reason of his employment as an airman, unable to perform an act required to be done either forthwith or on the happening of a certain event or within a specified time, he shall be deemed to have complied therewith if he performs the act as soon as is reasonably practicable, although after the happening of the event or the expiration of the specified time.