Remaining stable enough to allow for the fuel transfer between two aircraft at high speeds in midair can require pinpoint flying, though the process is eased through constant communication.

Aerial refueling, one of the most important force-multipliers in modern aviation, allows an aircraft to stay aloft for far longer than just their internal fuel tanks would allow—resulting in extended range, time on station, and global reach. Without aerial refueling, modern air force operations like long-distance bombing, transoceanic fighter deployments, or persistent combat patrols would likely be impossible, at least in their current form.

While aerial refueling looks quite simple, the act of two aircraft flying in close formation—and passing fuel from one to the other—is in reality complex, specialized, and quite hazardous. 

The Two Methods for Aerial Refueling

Worldwide, two primary systems are used for aerial refueling. 

1. The “Probe-and-Drogue” Approach

The globally more common approach is the “probe-and-drogue” approach, involving a tanker trailing a flexible hose with a basket-shaped fitting (the drogue) at the end. The receiving aircraft, with a retractable probe, then inserts its probe into the drogue while both planes fly in tight formation. Once the probe is in the drogue, pumps transfer fuel from tanker to receiver. The process is mechanically simple and even allows for multiple hoses to be deployed from a single tanker aircraft at once. However, the method refuels at a relatively slow rate—making it workable for smaller fighters and carrier aviation, but impractical for refueling bombers or large transport aircraft midair.

2. The “Flying Boom”

The “flying boom” is the favorite of the US Air Force. More complex than the probe-and-drogue, the flying boom transfers fuel into the receiving aircraft much faster. The system relies on a tanker extending a rigid, telescoping tube, called the “box,” which is controlled by a tanker crew member known as the boom operator. From the rear of the tanker, the boom operator “flies” the boom into a receptacle on the receiving aircraft using small control surfaces on the boom itself. Once the boom is connected to the receiving aircraft, a far more powerful pump transfers thousands of pounds of fuel per minute. And while the boom system can only refuel one aircraft at a time, the fuel flow rate is such that the system is ideal for refueling larger aircraft like bombers and transports.

Aerial Refueling Can Be Quite Dangerous

Whether probe-and-drogue or flying boom, aerial refueling requires dextrous flying. Tankers and receivers are forced to maintain a stable relative position within just a few feet of one another—despite the challenges associated with turbulence, crosswinds, or the slipstream effect created in the tanker’s wake. Under more extreme circumstances, remaining stable enough to allow for the fuel transfer can require pinpoint flying. The process is eased through constant communication; receiving pilot and boom operator are constantly discussing alignment, speed control, and safety throughout the process. 

The hardships of aerial refueling are strategically worth it. Fighters, typically with modest combat radiuses, can deploy across oceans thanks to aerial refueling every few hundred miles. Similarly, strategic bombers can be launched from the continental United States, strike targets overseas, and return home without ever landing—as demonstrated in the recent “Operation Midnight Hammer” B-2 strike against Iran. And because only a handful of nations possess the large tankers required to sustain long-range combat operations, the global strategic implications of aerial refueling are immense. Indeed, the seemingly humble ability to pump gas while airborne has ramifications for the balance of global power.