There may be a further complication, in the UK there are such things as Members Clubs, which could operate an airstrip. Each member is an owner of all the club assets and has an equal right to use them.
So although the treasurer has taken the days takings home to be counted, and set the signal square with the yellow cross, the member can call the place 'open' and land. He will also know the pass code to operate the locked electronic Front Gate, so be able to drive home.