Fuel if you think its overFuel remains the largest variable cost for low cost carriers. Its share price decline reflects concerns that rapid growth has left the balance sheet more exposed than Ryanair’s conservative approach. Those who viewed low cost airlines as defensive growth stocks now see greater cyclical risk. Markets reacted negatively in the short term but longer term investors may view the update as an opportunity to reassess fundamentals. Low cost carriers led the rebound because of their ability to stimulate demand with low fares.