Airmail (or air mail) is mail that is transported by aircraft. It typically arrives more quickly than surface mail, and costs more to send. Airmail may be the only option for sending mail to some destinations, such as overseas, if the mail cannot wait the time it would take to arrive by ship, sometimes weeks. A postal service may sometimes opt to transport some regular mail by air, perhaps because other transportation is unavailable, but it is usually impossible to know this by examining an envelope, and such items are not considered "airmail".
A letter sent by airmail may be called an aerogramme, aerogram, air letter or simply airmail letter. However, aerogramme and aerogram may also refer to a specific kind of airmail letter which is its own envelope; see aerogram.
The choice to send a letter by air is indicated either by a handwritten note on the envelope, by the use of special labels called airmail etiquettes, or by the use of specially-marked envelopes. Special postage stamps may also be available, or required; the rules vary in different countries.
The study of airmail is known as aerophilately.
Although carrier pigeons had long been used to send messages (an activity known as pigeon mail), the first mail to be carried by an air vehicle was on 7 January 1785, on a balloon flight from Dover to France near Calais. Balloons also carried mail out of Paris and Metz during the Franco-Prussian War (1870), drifting over the heads of the Germans besieging those cities. Balloon mail was also carried on an 1877 flight in Nashville, Tennessee.
The introduction of the airplane in 1903 generated immediate interest in using them for mail transport, and the first official flight took place on 18 February 1911 in Allahabad, British India, when Henri Pequet carried 6,500 letters a distance of 13 km. Many other flights, such as that of the Vin Fiz Flyer, ended in disaster, but many countries had operating services by the 1920s.
Since stamp collecting was already a well-developed hobby by this time, collectors followed developments in airmail service closely, and went to some trouble to find out about the first flights between various destinations, and to get letters onto them. The authorities often used special cachets on the covers, and in many cases the pilot would sign them as well.
The dirigibles of the 1920s and 1930s also carried airmail, known as dirigible mail. The German zeppelins were especially visible in this role, and many countries issued special stamps for use on zeppelin mail.
In the 1950s, general enthusiasm for rockets led to experiments with rocket mail. There was a single use of Missile Mail by the United States in 1959; see: USS Barbero. None of the various schemes went into production use, although many souvenir covers exist. A number of spacecraft have also carried space mail, sometimes in rather large quantities, all unabashedly for promotional purposes. The study of these is known as astrophilately.
In the United States, separate higher priced postage stamps were long required for domestic airmail, but in 1977 the United States Postal Service initiated all domestic first class mail, land or air, would be delivered by the most speedy practical option for a standard first class stamp.
- Info on early airmail service (http://www.ukrweekly.com/Archive/2000/490021.shtml)