Sec.  22.873   Construction requirements for commercial aviation air-ground
systems.

   Licensees authorized to use more than one megahertz (1 MHz) of the 800 MHz
   commercial aviation air-ground spectrum allocation (see  Sec. 22.857) must make a
   showing of “substantial service”' as set forth in this section. Failure by
   any such licensee to meet this requirement will result in forfeiture of the
   license and the licensee will be ineligible to regain it. Licensees
   authorized to use one megahertz or less of the 800 MHz commercial aviation
   air-ground spectrum allocation are not subject to the requirements in this
   section.

   (a) “Substantial service” is defined as service that is sound, favorable,
   and substantially above a level of mediocre service that just might
   minimally warrant renewal.

   (b) Each commercial aviation air-ground system subject to the requirements
   of this section must demonstrate substantial service within 5 years after
   grant of the authorization. Substantial service may be demonstrated by, but
   is not limited to, either of the following “safe harbor” provisions:

   (1) Construction and operation of 20 ground stations, with at least one
   ground station located in each of the 10 Federal Aviation Administration
   regions; or,

   (2) Provision of service to the airspace of 25 of the 50 busiest airports
   (as measured by annual passenger boardings).

   [ 70 FR 19310 , Apr. 13, 2005]