Internationally, the letter K identifies tanker aircraft (tanKer), whose main mission is to transfer fuel to other aircraft. The first in-flight refueling (REVO in Portuguese) occurred over 100 years ago in the United States, but it was only after the Second World War that the practice became common in the military.
REVO is crucial to extending aircraft autonomy, enabling long-duration missions, even in combat scenarios where logistical is limited. The technique reduces the need for stopovers and increases the flexibility of air operations.
Furthermore, it is essential for the effectiveness of armed forces and for carrying out humanitarian or emergency missions, where every minute counts.
In Brazil, REVO became a reality in 1976, when the Brazilian Air Force received its first tanker aircraft in the form of two KC-130 Hercules. Since then, the FAB has used three models of this type of aircraft to refuel its fighters in flight.
Let's learn a little about each of the Brazilian tanker aircraft.
KC-130 Hercules: the pioneer
Seeking to expand and modernize its air transport capacity, the FAB acquired its first Lockheed C-1964 Hercules in 130. Versatile and robust, the American-made model was one of the most important vectors in Brazilian military history, participating in important missions during its career.
Among the milestones achieved by Brazilian Hercules is the first in-flight refueling in the country. In the 1970s, the FAB was undergoing a major modernization process, which began with the purchase of French Dassault Mirage IIIs, the implementation of the Brazilian air defense system, and the purchase of Northrop F-5 Tiger II fighters. The F-5s were purchased with so-called probes, an instrument installed on the side of the fuselage that allows REVO.
To fuel its new jets while still in the air, the FAB purchased a pair of KC-130Hs in 1974. This is a C-130H, adapted to transfer fuel in flight.
In addition to the original tanks, the KC-130 receives two more fuel tanks installed in the cargo area. At the tip of each wing, the “Hercules-Tanque” received a “pod”, containing a hose with a stabilizer at the end, called a basket, where the fighter docks the probe to receive fuel.
The two tankers, registration FAB 2461 and 62, arrived in the country in January 1976 and were incorporated into the 1st Troop Transport Group. In May of that same year, the first aerial refueling in the history of the FAB took place, between the KC-130, registration FAB 2461, and F-5E fighters of the 1st Fighter Aviation Group. From this event on, the radio code BARÃO became a symbol of the in-flight refueling activities with the KC-130.
The Hercules was the longest-lived of the FAB's KCs, transferring fuel to F-5, A-1 and Mirage 2000 fighters for almost 50 years. It was also with the veteran turboprop that Brazil became the first country in South America to refuel a helicopter in flight, with the H-36 Caracal. In December 2023, the C-130s left the FAB's operational service, being officially retired in February of this year.
KC-137: the jet-powered REVO
Almost ten years after the first REVO between a Hercules and a Tiger, the Air Force bought “new” tankers, this time the first powered by jet aircraft. In a deal with Varig, four Boeing 707-320 and 340 enger jets were purchased. Manufactured in the 1960s, the 707s would be designated KC 137 in the FAB.
As soon as they left the airline, the Brazilian Air Force 707s were taken to the United States, where Boeing itself transformed them into tanker aircraft.
In addition to receiving an auxiliary power unit (APU) and a retractable ladder, the 707s received structural reinforcement, more fuel tanks and a pair of REVO pods, installed on the wingtips like the KC-130. Each “pod” accommodated a 10,6-meter-long hose. ed 2401 to 2404, the jets were operated by the Corsair Squadron throughout their operational life, from 1986 to 2013.
While the Hercules was a tactical tanker, the KC-137 was a strategic tanker. The jet was faster, had greater range and its approximately 90 liters of fuel allowed for several REVOs with Brazilian fighters. An important vector, especially considering the large size of Brazil.
At the same time, Boeings were also widely used to transport troops, cargo, and in humanitarian missions. In the specific case of the 2401, the former Varig became the Brazilian presidential jet, while sharing military duties.
Popularly, the KC-137s were called Scrap, due to the age, noise and smoke generated by the aircraft. The nickname was also a reference to the VC-96, a 737-200 also used to transport national authorities: in addition to the nickname Breguinha, the FAB's 737-200 was also called Sucatinha.
Upon completing 25 years of service with the FAB in 2011, the KC-137s were already showing some signs of age, after all, they were aircraft manufactured in the 1960s. Maintenance was expensive and laborious, since the end of 707 production in 1992 made the supply of parts very difficult.
At the time, the Air Force Command was already looking for a successor in the form of three Boeing 767s, also transformed into tanker aircraft, but which never arrived due to lack of resources.
In May 2013, an accident in Haiti involving FAB 2404 decreed the end of the military 707 in Brazil and in October of the same year, the FAB retired the Sucatão. Unfortunately, no aircraft was preserved, all were turned into scrap.
KC-390 Millennium: national giant
In 2009, Embraer and the Air Force ed forces to develop a new tactical transport and air refueling aircraft. The mission was to provide the FAB with – and introduce to the market – a modern aircraft, more capable than the North American C-130. Thus, the KC-390 was born, today one of the greatest successes of Embraer's military arm.
The model entered service with the FAB in 2019, which received in September 2024 the seventh of 19 cargo planes ordered. Also in service with the Portuguese and Hungarian air forces, the KC-390 has already performed troop transport, cargo drop, firefighting and aeromedical evacuation missions.
But it was in August 2022 that Millennium carried out its first in-flight refueling with the FAB. On that occasion, 46 years after the first FAB REVO, KC-390 2857 transferred fuel to F-5M fighters from the 1st GAvCa, in a training activity in Rio de Janeiro, with Embraer instructors and military personnel from the Zeus and Gordo squadrons.
Since then, the KC-390 has refueled the F-5 and AMX A-1 several times. The next step is to transfer fuel to the new Saab F-39 Gripen, to the H-36 helicopters and to the SC-105 Persuader turboprop search and rescue.
The KC-390's REVO system consists of three main components. A pair of tanks in the cargo compartment increase the jet's fuel capacity from 27 to 31 tons; Cobham 912 pods on the wingtips transfer the precious jet fuel to receivers through hoses about 30 meters long.
The third item is installed on top of the KC-390 fuselage: a REVO probe. The equipment allows the Millennium to be refueled in flight, becoming the first FAB cargo/tanker aircraft with this capability.
Bonus: Navy A-4 Skyhawk
So far, we've covered three large aircraft. In this little bonus, the tanker aircraft is smaller than the FAB's F-5. This is the A-4 Skyhawk of the Brazilian Navy (MB).
The A-4s, called AF-1 Falcão by the Navy, were purchased in the 1990s to operate aboard aircraft carriers. Since space on these ships is limited, the A-4s can act as tanker aircraft, through the so-called Buddy Store. The equipment is similar to that found on other tankers, consisting of a pod with a hose and a pump that pressurizes the fuel, transferred from underwing tanks.
Logically, the fuel capacity is much smaller, with the A-4 being able to transfer around 907 kilos of kerosene, or a little more if it is necessary to use the naval jet's internal fuel.
In October 2016, an unprecedented t activity between the FAB's 1st Air Defense Group and the Navy's 1st Interception and Attack Aircraft Squadron saw the first REVO between fighters in Brazil, with the A-4 transferring fuel to the F-5 fighters, then operated by the Air Force unit, now equipped with the modern F-39s.
