Delta Air Lines’ 2012 acquisition of the Monroe refinery in Philadelphia serves as a strategic asset against rising jet fuel prices.

The widening crack spread between crude oil and jet fuel costs increases expenses for most airlines.

Delta hedges against market volatility by retaining refining profits that would otherwise go to external suppliers.

CEO Ed Bastian expects the refinery's meaningful hedge to contribute to corporate profits starting in the second quarter.

These earnings will partially offset hundreds of millions added to the airline's fuel bill.