<i>Don&#x27;t most airlines work through a 3rd party that actually purchases and owns the planes?</i><p>this is driven by the fact that airlines don&#x27;t consistently have taxable income. If you have net operating losses, which airlines often do, you can&#x27;t fully take advantage of the tax shield provided by depreciation. Airplanes are big capital assets, hence they provide a large tax shield. That&#x27;s why you often see financial entities (e.g. banks, insurance companies) who have regular taxable income have leasing arms.