Air-mail

Airmail (or air mail) is a mail transport service branded and sold on the basis of being airborne. Airmail items typically arrive more quickly than surface mail, and usually cost 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. The Universal Postal Union adopted comprehensive rules for airmail at its 1929 Postal Union Congress in London. Since the official language of the Universal Postal Union is French, airmail items worldwide are often marked Par avion, literally: "by airplane".

For about the first half century of its existence, transportation of mail via aircraft was usually categorized and sold as a separate service (airmail) from surface mail. Today it is often the case that mail service is categorized and sold according to transit time alone, with mode of transport (land, sea, air) being decided on the back end in dynamic intermodal combinations. Thus even "regular" mail may make part of its journey on an aircraft. Such "air-speeded" mail is different from nominal airmail in its branding, price, and priority of service.

Specific instances of a letter being delivered by air long predate the introduction of Airmail as a regularly scheduled service available to the general public.

Although homing 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 January 7, 1785, on a hot air balloon flight from Dover to France near Calais. It was flown by Jean-Pierre Blanchard and John Jeffries. The letter was written by an American Loyalist William Franklin to his son William Temple Franklin who was serving in a diplomatic role in Paris with his grandfather Benjamin Franklin.

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