.aero was developed in response to the growing need of the community, and is designed to create a structured, open and constantly evolving Internet naming architecture which will help the aviation community to integrate systems and service, and streamline communications within the community and with its partners.
Two-letter codes under .aero are reserved for airlines according to the IATA Airline Designators. While three-letter codes were initially reserved for airports (IATA airport code), they were released for registration by the larger aviation and aerospace community on December 1, 2008.
The aero top-level domain was initially approved in 2001 for a 5-year term expiring December 17, 2006 as part of a proof-of-concept of new top-level domains. The agreement was extended in October 2006 for a six-month term until June 17, 2007, and continued to be renewed on a June–December six-month cycle through June 17, 2009. In 2009, SITA and ICANN completed a new 10-year sponsorship agreement for the operation of aero.
Airlines, airports, and other parts of the air-travel industry
Players in this industry seem to be using it, further usage just like .com, .info and other TLDs
Credentials of applicants are checked before registration is permitted, but then any domain can be registered
Some categories of users can register at the second level and others at the third level within appropriate second level names; some industry codes such as those of airports and airlines were automatically linked to appropriate sites even if unregistered.