The chief executive of Southwest Airlines announced in July of 2008 that they had budgeted for $4 jet fuel.  But it turned out that what Southwest wasn't ready for was $2 jet fuel.

Southwest made some bad bets earlier this year while trying to lock in low fuel costs.  Now, they are paying a heavy price just when they should be celebrating lower costs. The company went into the red for the first time in 17 years when they suffered a $189 million loss on fuel contracts.

Southwest is not the only airline. Though plunging oil prices have been a slight relief for the airlines, many companies are still covering high costs they locked in months ago.