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(Upgrades are not available on fares in the L, T, and U range, however, which are the most deeply discounted.) To calculate the price of an upgrade, Delta charges a dollar amount per 500 miles. $50: Up to 500 miles. $75: 501-1000 miles. $100: 1001-1500 miles.
Getty Images. The refinery near Philadelphia that Delta bought in 2012. Sky-high fuel costs have made cost-cutting, not growing market share, the mantra for many airlines. One of Delta's riskier cost-cutting moves, buying an oil refinery, looks like it's starting to pay off.Delta bought the refinery, which is in Trainer, Pa., just outside of Philadelphia, in 2012 for $150 million as a way to hedge against its biggest expense, jet fuel costs.The idea was to become a price influencer, Delta CEO Richard Anderson said.etty Images. The refinery near Philadelphia that Delta bought in 2012. Sky-high fuel costs have made cost-cutting, not growing market share, the mantra for many airlines. One of Delta's riskier cost-cutting moves, buying an oil refinery, looks like it's starting to pay off.