The US Air Force wants to buy dozens of new tankers to fill a gap between the last expected deliveries of KC-46As and a future advanced design.
Lockheed Martin has formally unveiled its proposal, dubbed LMXT, to meet the U.S. Air Force’s requirements for additional aerial refueling tankers currently referred to simply as KC-Z. The project is to officially kick off by the end of next year.
The LMXT is based on the popular Airbus A330 Multi Role Tanker Transport (MRTT).
Lockheed’s proposal includes additional defensive capabilities and the ability to carry 13 tons additional fuel (Maximum fuel load over 135 tons).
Presently the US Air Force has an aging fleet of just under 400 KC-135’s, as well as its smaller fleet of KC-10As, the latter are already being retired. The service only expects to buy 179 KC-46As across 13 production lots. Boeing is widely expected to propose additional KC-46A orders for the KC-Y competition, which could lead to the winner getting a contract to build up to 160 new aircraft.
“Lockheed Martin has a long and successful track record of producing aircraft for the U.S. Air Force, and we understand the critical role tankers play in ensuring America’s total mission success,” said Greg Ulmer, Executive Vice President of Lockheed Martin.
Airbus previously worked with Northrop Grumman to pitch the A330 MRTT on multiple occasions, before ultimately losing out to Boeing’s KC-46A.
Lockheed Martin says the LMXT, which it would produce in the United States, builds on the proven capabilities of the A330 MRTT and will also include the more recently developed automatic boom/air-to-air refueling (A3R) system.
The A3R improves the speed at which tankers can link up with receiver aircraft and provides additional margins of safety for all aircraft.
The LMXT will also have a number of U.S.-specific features:
• Advanced networking and associated capabilities known as Joint All-Domain Command and Control (JADC2).
• Advanced communications relay nodes.
• Semi-autonomous “loyal wingman” self-defence drones.
• Advanced Battle Management System (ABMS).
The most significant component of the LMXT package is the added fuel capacity.
The standard A330 MRTT, with its maximum fuel load of 111 tons, already carries more gas than the KC-46A. By adding 13 more tons on top of that will not only allow the LMXT to refuel more aircraft per sortie, but give the tanker itself greater overall range and time on station.
A negative is that the LMXT lacks a main cargo deck with a large side-opening door for oversized loads. This feature is largely underappreciated on the Air Force’s existing tankers,
and is the reason they carry the “KC” or “Tanker Cargo” nomenclature. This allows secondary cargo and passenger carrying roles.
However the even greater emphasis is on aerial refueling, rather than other roles.
Lockheed Martin clearly hopes that the LMXT’s massive fuel load, along with its other features, will set it firmly apart from the KC-46A, which has struggled for years, due to technical issues and quality control problems.
Lockheed Martin’s press release notably says that its A330 MRTT-based offering will have a “proven fly-by-wire boom” and “operational and combat proven advanced camera and vision system.” These reflect major issues that the US Air Force is dealing with on its tankers.
Many earlier tanker designs, such as the KC-135 and KC-10, have the boom operator physically lie at the rear of the aircraft. From there they steer the end of the boom into the receiving aircraft. The A330 MRTT puts the boom operator in the aircraft’s main cabin, where they use a remote vision system, linked to an array of cameras at the back of the plane, to perform their task.
Boeing is in the process of developing fixes for both the remote vision system and the boom, which are both years away from being integrated into the majority of KC-46As that the Air Force now use.
The U.S. Transportation Command, in cooperation with the Air Force, has been exploring options for contractor-owned and/or operated tankers to support a variety of non-combat refueling. Even if the Air Force decides against buying LMXTs as a bridge tanker for its own use, a simplified version of the plane without the networking and other advanced capabilities could offer an attractive option for contractors, including Lockheed Martin and Airbus themselves, who are looking to exclusively provide refueling services to the Royal Air Force.
To date, Lockheed Martin and Boeing are the only two companies to submit bridge tanker proposals and it looks like it will be a very heated competition.
Edited, source – Aviation Weekly