Oregon Revised Statutes Revenue and Taxation § 308.559

(a) “Facility” includes all buildings or areas designed and used exclusively for major work at or near an airport, except passenger or freight terminals.

(b) “Major work” includes all remodeling, renovation, conversion, reconversion, repairs or scheduled maintenance performed at a facility in which the total labor expended for the work exceeds 10 work hours.

(2)(a) Any aircraft used or held for use by an air transportation company is exempt from ad valorem property taxation for the total period of time the aircraft is awaiting or undergoing major work at a facility located in Oregon.

(b) An exemption may not be granted under this section unless the air transportation company provides separate traffic statistics and other documentation demonstrating the major work to the Department of Revenue as part of a report filed either within the time required under ORS 308.520 or as extended under ORS 308.535. If the department determines that insufficient records and other information have been provided by the air transportation company to substantiate the period of time that the aircraft is claimed to be awaiting or undergoing major work in a facility, the department may deny the exemption.

(b) Any exemption under this subsection shall be reviewed annually by the department using documentation provided by the air transportation company as part of the annual report filed either within the time required by ORS 308.520 or as extended under ORS 308.535.