I really don't think it is fair to impugn the motives and character ( " ...Landlubbers only willing to serve on their own terms....)" of those who did not expect to go to sea when they joined the RAF. We have three services, each with their own conditions of service and we freely choose which to join depending on what appeals to us. How would our heroic aircrew and maintainers of the RN feel about spending six months of each year in a trench with the infantry?