US airspace
5 min read

Here is an interesting piece of aviation history that helps explain the rules we fly by, especially internationally. In much earlier times, no one seemed to worry about who owned or controlled the airspace in which aircraft would eventually fly. Wartime concerns changed that. This apathy slowly began to dissipate as airborne vehicles became more of a wartime threat. A report of one of the earliest war uses of aviation is in an early edition of the Encyclopedia Britannica that tells “balloons were … employed by the French during this campaign [Holland 1794] to procure knowledge of the position of the enemy. An engineer ascended in the balloon (which was suffered to rise to a great height, but prevented from being carried away by a long line), made plans of the enemy’s encampment, and during an attack sent down notice of every hostile movement.”

Early balloon

Debates about airspace predate the Wright Brothers.

For a long time no attempts were made to address this situation until the turn of the nineteenth century. Then, in the proceedings of the Hague Tribunal in 1899, the representatives of the nations attending the International Peace Conference declared that they would prohibit the launching of projectiles and explosives from balloons, or by other new methods of a similar nature, for a period extending to the close of the third peace conference. The international control of aerial navigation was begun, but only from a military standpoint.

Remember, it wasn’t until 1903 that the Wright Brothers made their first powered flight. So even before that, the military application of aviation was well on its way toward shaping the development of international air law. The peaceful use of the airspace, as a significant consideration, was way behind.

At this time there were two theories on the status of airspace for international air navigation. One argued for freedom of airspace much like the freedom of the seas, by which the countries underlying the airspace exercised no sovereignty in the airspace and flight was free. The other argued that the airspace above national territories was not free, but subject to the sovereignty of the underlying country.

The debate over which theory should prevail was still raging in 1909 when Bleriot flew from France across the English Channel to Great Britain in his monoplane. Two years later the airplane dropped its first bomb, fired its first volley from a mounted weapon, and successfully conducted the first airplane reconnaissance in time of war. These events seemed to cap off the debate. The governments of the world were now thinking strongly in terms of jurisdiction in the airspace above them.

The coup de grace to the freedom of the airspace theory seemed to come during World War I. In 1914, the Netherlands, a neutral country in the war, sent a diplomatic note to the government of Germany protesting the flight of two German Zeppelins over its territory. The overflights were unintentional – even then, weather and poor visibility wreaked havoc with the most carefully made flight plans. The Dutch complained to Germany that flying over Dutch territory without Dutch consent was incompatible with respect for its national sovereignty. In 1916, a German Zeppelin again drifted into the airspace over Dutch territory. Without warning, the Dutch shot at it. By this direct and affirmative action, the government of the Netherlands had become the outstanding advocate for national air sovereignty.

Every international aviation convention since then recognized the complete and exclusive sovereignty of each nation in the airspace above its territory, expanding its jurisdiction to cover civil as well as military flying. And as nations began to enact aviation laws, they began to assert this sovereignty. In 1926 the United States enacted the Air Commerce Act, our first aviation statute, which declared “complete sovereignty of the lands and waters of the United States, including the Canal Zone.”

US airspace

Unlike the high seas, the US owns the airspace above its land.

This theory has persisted to the present day and is embodied in the Chicago Convention. This Convention sets out the international law under which we derive our rights and privileges in international flight, in so far as the flight involves nations that adhere to the Convention (virtually all the civilized nations of the world).

Article 1 of the Convention states that “the contracting States recognize that every State has complete and exclusive sovereignty over the airspace above its territory.” The Convention then goes on to grant the right of international flight in Article 5.

You hangar flying lawyers may have already thought of some interesting questions raised by Article 1. Since there is freedom of the seas, what about the airspace over the high seas? Well, it is well settled as a principle of international law that the high seas airspace may be used by every nation, and that none of such airspace may be subjected to the exclusive and complete sovereignty of any nation. And what about outer space? It is also well settled that outer space is free for exploration and use by all nations and is not subject to national appropriation by claim of sovereignty or other means.

While interesting to many, these questions today are more theoretical than real for the general aviation pilot. What is real to us is this development of the law up to the Chicago Convention that led to our right of international flight (with limitations). We’ll cover that in a subsequent column.

John Yodice