14 CFR 271.2 - Definitions.
As used in this part:
Eligible place means a place in the United States that -
(1) Was an eligible point under section 419 of the Federal Aviation Act of 1958 as in effect before October 1, 1988;
(2) Received scheduled air transportation at any time between January 1, 1990, and November 4, 1990; and
(3) Is not listed in Department of Transportation Orders 89-9-37 and 89-12-52 as a place ineligible for compensation under Subchapter II of Chapter 417 of the Statute.
Essential air service is that air transportation which the Department has found to be essential under Subchapter II of Chapter 417 of the Statute.