KC-46 Pegasus vs A330 MRTT, Which Tanker Wins

In the KC-46 vs A330 MRTT contest, the Airbus tanker carries roughly 111 tonnes of fuel against the Boeing’s 96, and has years more operational history, while the KC-46 remains the USAF’s choice. Both are twin-engine airliner conversions. They differ most in size, maturity and how they have fared with customers.

~111 t

A330 MRTT fuel load, per Airbus

~96 t

KC-46 fuel load, per Boeing and USAF

2011

Year the USAF picked Boeing

70+

A330 MRTTs reported in service worldwide

KC-46 vs A330 MRTT overview

The two tankers go back to the same competition. The US Air Force’s KC-X program pitted a Boeing 767-based design against an Airbus A330-based one, and after a long series of protests and rebids, Boeing won in 2011 with a lower fixed-price bid. Airbus went on to sell its tanker to a steadily growing list of other air forces.

The result is a clear split in the market. The A330 Multi Role Tanker Transport, known as MRTT, is the main tanker outside the United States. The KC-46 Pegasus is the main new tanker inside it.

KC-46 vs A330 MRTT specifications

KC-46A and A330 MRTT side by side

Specification	KC-46A Pegasus	A330 MRTT
Base aircraft	Boeing 767-2C	Airbus A330-200
Engines	Two PW4062	Two Rolls-Royce Trent 700, GE CF6 or PW4000 depending on customer
Length	About 50.5 m	About 59 m
Wingspan	About 48 m	About 60 m
Maximum takeoff weight	About 188 t	About 233 to 247 t depending on variant
Fuel capacity	About 96 t	About 111 t, plus optional extra tanks
Maximum cargo	About 29 t	About 45 t, per Airbus
Passengers	Up to about 114	Up to about 300
Boom offload	Roughly 1,200 US gal/min (about 4,500 l/min) claimed	Comparable boom offload, per Airbus
Hose systems	Wing pods and centerline drogue	Wing pods and centerline fuselage unit
Approximate unit cost	$150 to $200 million, press estimates	Often $150 million or more, varies by buyer and fit

Source: Airbus and Boeing product literature, USAF fact sheets. Figures are rounded and depend on configuration and buyer; manufacturer claims where noted.

Refueling systems compared

Both tankers use a flying boom and probe-and-drogue hoses, but the operator experience differs. The A330 MRTT’s Air Refueling Boom System uses cameras and a three-dimensional display from the operator’s console, and Airbus also provides an automatic boom mode in some installations. The KC-46’s Remote Vision System has the same basic idea, but its early versions suffered problems with depth perception and glare, which we cover in our transport and tanker coverage.

The Airbus tanker has a broader set of fuel delivery choices. It can carry a fuselage refueling unit that supports large receivers with hoses in addition to wing pods, while the KC-46 uses a centerline drogue and wing pods. Both can also receive fuel themselves, and both can carry cargo in the lower deck or on the main deck.

Who operates each tanker

Main operators

Tanker	Operators
KC-46A	US Air Force, Japan Air Self-Defense Force; more export customers are limited
A330 MRTT	Royal Air Force (Voyager), Australia, France, Spain, Saudi Arabia, UAE, Singapore, South Korea, Canada, the NATO multinational fleet and others

Operators listed from company and press sources; customer lists change as orders and deliveries continue.

Airbus has sold the MRTT to air forces across Europe, the Middle East and Asia, and a multinational fleet run through NATO pools aircraft for several European countries. The Air Force has also looked at adding an A330-based tanker proposed by Lockheed Martin, called the LMXT, to fill a gap before its next-generation tanker arrives. Timelines and commitments have shifted with the budget, so check current announcements.

Which tanker is better

Range and fuel offload

The A330 MRTT wins on raw numbers: more fuel, more cargo and more passengers. On long Pacific or transoceanic routes, a bigger tanker can support more receivers per sortie.

Maturity and support

The MRTT has been in service for longer with fewer widely reported issues, and its operator base provides a reliable body of experience. The KC-46 is catching up, but still has the Remote Vision System fix to complete.

Politics and basing

The KC-46 is built in the United States, is integrated with US systems and benefits from US domestic preferences. It is also smaller, which can help at airfields with weight or ramp limits. The USAF’s existing KC-46 fleet, with more than 100 delivered, makes it the baseline for the service.

Editor’s read

The fairest verdict is that they are different answers to different problems. For a US-centric fleet that needs one more-modern tanker at scale, the KC-46 is the incumbent and will keep flying. For an export customer buying a few aircraft and needing proven capability, the MRTT has been the safer buy so far.