If the original cost for leased aircraft cannot be determined from information reasonably available to the taxpayer, original cost may be determined by reference to the "average new prices" column of the Airliner Price Guide for that model, series, and year of manufacture of aircraft. If information is not available in the "average new prices" column for that model, series, and year, the original cost may be determined using the best indicator of original cost plus all conversion costs incurred for that aircraft. In the event of a merger, bankruptcy, or change in accounting methods by the reporting airline, there shall be a rebuttable presumption that the cost of the individual aircraft and the acquisition date reported by the acquired company, if available, or the cost reported prior to the change in accounting method, are the original cost and the applicable acquisition date.
If the original cost for leased aircraft cannot be determined from information reasonably available to the taxpayer, original cost may be determined by reference to the "average new prices" column of the Airliner Price Guide for that model, series, and year of manufacture of aircraft. If information is not available in the "average new prices" column for that model, series, and year, the original cost may be determined using the best indicator of original cost plus all conversion costs incurred for that aircraft. In the event of a merger, bankruptcy, or change in accounting methods by the reporting airline, there shall be a rebuttable presumption that the cost of the individual aircraft and the acquisition date reported by the acquired company, if available, or the cost reported prior to the change in accounting method, are the original cost and the applicable acquisition date.
Ca. Rev. and Tax. Code § 401.15