U.S. military aircrews are reportedly relying on Modafinil tablets, known as "go pills," to maintain alertness during extended missions targeting Iran. These operations, part of what is internally termed "Operation Epic Fury," have seen significant increases in flight durations, with some round trips now extending up to 18 hours from a previous 10.5 hours for bombers.

The necessity for these longer routes stems from flight restrictions imposed by several European nations. Spain has enacted a blanket flight ban, while France, Italy, Britain, Switzerland, and Austria have placed limits on certain aircraft involved in the operation. These measures compel U.S. forces to reroute aircraft either northeast over Europe or south across the Atlantic, through the Strait of Gibraltar, and along the Mediterranean.

Aircraft such as B1-B and B-52 bombers departing from Royal Air Force (RAF) Fairford in Gloucestershire, UK, now require more frequent aerial refueling. What previously involved up to four tanker rendezvous for a return flight can now necessitate as many as eight delicate refueling maneuvers. Similarly, F-15 Strike Eagle fighters based at RAF Lakenheath, Suffolk, are also undertaking additional tanker top-ups, with their round trips, including combat zone "time on station," lasting 12 to 15 hours.

The extended demands are also testing the endurance of B-2 Spirit stealth bombers, which are undertaking marathon round-trip strikes from Whiteman Air Force Base in Missouri. Their mission times have reportedly increased from approximately 32 hours to a gruelling 40 hours. The United Kingdom has declined to permit B-2 operations from its territory, classifying them as strategically offensive aircraft, in contrast to other bombers involved in what are described as defensive actions.

These restrictions have added considerable complexity to the campaign's logistics. Spain's flight denials, reportedly based on the view that the U.S. operation is illegal, are particularly impactful as its Morón air base in Andalusia serves as a critical hub for U.S. tanker fleets and strategic airlift for Africa. The increased pace of tanker operations and the density of aircraft in eastern Mediterranean refueling corridors are believed to have contributed to a recent collision involving two KC-135 tankers over Iraq, which resulted in six crew fatalities.

The altered flight paths are also making U.S. operations more susceptible to public monitoring, as commercial flight-tracking sites can trace the movements of tankers, which typically broadcast ADS-B data.

U.S. commanders are reportedly expressing frustration with European leaders over these diplomatic hurdles, which have become a significant consideration in flight planning alongside traditional factors such as weather and operational efficiency. Separately, an F-15E fighter jet, reportedly originating from a U.S. Air Force base in the Middle East, was shot down in Iran on Friday.