I've previously mentioned the Holden airship. At the moment it is at Brisbane, and there are concerns that it will be flown over the Gabba during the first Ashes test next month.1 The problem is that Holden isn't paying Cricket Australia anything for the privilege of flying a billboard over the cricket ground, where it might well catch the eye of 40000 spectators bored with Australia's on-field drubbing of the puny English team. So the Queensland state government is planning to introduce legislation to ban such overflights of major sporting events, along with skywriting. Otherwise, the downfall of Australian civilisation could result, or something.
Now, I've said it before and I'll say it again: there's no need for legislation here. It would likely just impose a fine for infractions, anyway, which might not be an effective deterrent to a sufficiently determined advertiser. A FAR more effective solution would be a belt of anti-aircraft guns around the Gabba, along with a squadron or two of Sopwith Camels and a system of sound locators and ground observers in surrounding suburbs. It worked in the First World War; it can work again.
Of course, the enemy advertisers may adapt, seeking to overwhelm the defences with masses of airships, or to escort the raiders, perhaps with trapeze fighters. Maybe the blimp will always get through, in which case a deterring counter-advertising strategy might well be called for -- holding a force of airships in readiness to instantly fly over sporting events sponsored by the opposition, should they dare to use their airships in a hostile manner. Perhaps the ultimate solution is the international control of all airships, which would then only be used over stadiums as directed by the League of Nations -- I mean, United Nations.
At any rate, I'm available, for only a moderately immoderate fee, to consult with any sporting venues wishing to develop a state-of-the-art-c.-1918 air defence system.
Note to journos: outside of a few not-notably-successful experiments, blimps AKA airships do not rely upon hot air for lift. This one has 5 million litres of helium inside it. ↩