March 30, 2011:
On March 22nd, two jet fighters, flying from Qatar to Italy to take part in enforcing the Libyan no-fly zone had to make an unplanned refueling stop in Cyprus. This was not unexpected, as flying fighters long distance depends a lot on unpredictable weather conditions, particularly which direction, and at what speed, the wind is blowing. So fighters doing a long distance flight either plan for emergency refueling stops, or have aerial tankers available.
This problem was first encountered during World War II in the Pacific. There, very long flights by fighters, either to just to get to a new base, or simply to reach the enemy, forced pilots to develop new flying techniques to complete some of these flights. Expert pilots figured out how to get the most range out of each aircraft type, and commanders learned to not even attempt long flights over some areas prone to unexpected headwinds or storms. Fighters could always be moved, more slowly, by smaller transport carriers or, broken down (winds and tail removed) in freighters.
During World War II, aerial refueling was developed, but it only became common in the decades after the war. Now, it is practically standard for many fighters and nearly all heavy bombers. Those unexpected head winds are still a problem, especially on trans-oceanic flights, but aerial refueling is usually available to prevent a lost aircraft.