Which aircraft is known as the RAF's air refueling tanker?

The Voyager is recognized as the Royal Air Force's (RAF) primary air refueling tanker. It is based on the Airbus A330 aircraft and is a versatile platform for in-flight refueling for both British and allied forces. The Voyager provides the capability to refuel a wide range of aircraft, significantly extending their range and operational capability during missions. This capability is essential for the RAF as it allows for longer duration flights and the ability to cover greater distances without the need for frequent landings.

In contrast, while the A400M Atlas is a military transport aircraft that has limited air-to-air refueling capability, it is not primarily designated as a tanker. The Typhoon is a multi-role fighter jet, and the F-35 Lightning II is a stealth multirole fighter, neither of which are primarily designed for refueling other aircraft. Thus, the Voyager stands out as the correct choice due to its dedicated role in air refueling operations within the RAF.