California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 1155
For purposes of Section 404, certificated aircraft shall be deemed to be situated only in those taxing agencies in which the aircraft normally make physical contact with sufficient regularity to entitle such agencies to tax the aircraft under the laws and Constitution of the United States. Flight time within the state shall be allocated as follows:
# (a)
If the aircraft takes off in one taxing agency which is entitled to tax (within the meaning of the preceding sentence) and lands in another agency which is entitled to tax, the flight time between such taxing agencies shall be allocated one-half to each such agency.
# (b)
If the aircraft arrives from out of state or leaves the state, the flight time from or to the state boundary shall be allocated to the taxing agency entitled to tax in which the aircraft first lands or last takes off, as the case may be.
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