Delta has now restarted its refinery that it bought last spring, and according to estimates from the airline, it looks like a good move. Delta expects the refinery to cut $300 million from its fuel bill over a year. The move shows how far airlines are willing to go to lower their jet-fuel bills, which often constitute more than 30% of operating expenses. While this is a bold move that should pay off in the long run, Brendan urges long-term investors to avoid airlines. Check out the following video for more on Delta and the industry overall.

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