INSIGHTi
Air Force Tanker Strategy Changes
Updated June 24, 2021
As discussed in the CRS report Air Force KC-46A Pegasus Tanker, the Air Force is in the process of
replacing its fleet of 396 KC-135 Stratotanker refueling aircraft, built in the 1950s and 60s, and 59 KC-10
Extenders, which entered service in 1981. Recent announcements indicate that the planned replacement
program is changing significantly from its original form, which Congress may consider in evaluating the
FY2022 defense budget requests.
The Air Force original y envisaged replacing the current tanker fleet in three stages.
An initial acquisition of 179 new aircraft procured through the KC-X competition (won
by the Boeing KC-46A) would replace roughly one-third of the KC-135 fleet.
A further 179 tankers were projected to be procured in a second solicitation cal ed KC-Y;
initial y projected as a new competition based on what aircraft were available at the time,
it was subsequently recast as a continuation of KC-46A procurement.
A third program, KC-Z, was to be a replacement for the KC-10 fleet, a larger tanker than
the KC-46. Subsequently, the Air Force dropped plans for the KC-Z, envisioning it
instead as a third tranche of KC-46s.
However, it now appears that tanker procurement plans have changed in at least two ways.
One is that the KC-Y program is to be a full and open competition rather than a follow -on KC-46
contract. The Air Force released a “sources sought” notice on June 16, 2021, seeking a commercial
derivative tanker aircraft. This would seem to limit the field to the KC-46 and the Airbus A330 Multi-
Role Tanker Transport. An earlier version of the A330 tanker lost to Boeing after three rounds of a
protracted and controversial KC-X competition.
The Air Force is referring to this prospective procurement as a “Bridge Tanker,” to fil in between the
current KC-X and future KC-Z; it is not clear how or whether that nomenclature distinguishes the
program from the already-scheduled KC-Y. The service projects issuing a formal request for proposals for
the Bridge Tanker by the end of calendar 2022.
In another change, the Air Force view of KC-Z has been evolving for some time, and the Bridge Tanker
sources sought announcement recast KC-Z as an “Advanced Air Refueling Tanker,” albeit without further
detail. This fol ows recent remarks by service leaders indicating an interest in focusing the former KC-Z
Congressional Research Service
https://crsreports.congress.gov
IN11537
CRS INSIGHT
Prepared for Members and
Committees of Congress
Congressional Research Service
2
less on the size of the tanker than on other attributes, such as stealth, autonomy, and/or whether it should
carry crew.
In a third difference from existing plans, the Air Force is actively exploring the notion of contract aerial
refueling. Under this construct, the Air Force would hire private contractors to supply and operate aerial
refueling aircraft to support training missions and other deployments, although not in combat areas. The
Navy has used similar services since 2001, and the United Kingdom entered into a similar arrangement in
2008. The Department of Defense has increasingly moved to contract services for a variety of previously
military support tasks, such as airlift and adversary air combat training.
The search for a “bridge” solution is driven in part by the increasing chal enge of keeping the current KC-
135 fleet airworthy, and by delays in delivery of ful y operational KC-46s. The Air Force sees a gap
between demand and the supply of available tankers, particularly over the next five to seven years.
The report accompanying the House version of the FY2020 Defense Authorization Act, H.Rept. 116-120,
required “the Secretary of the Air Force, in coordination with the Commander of U.S. Transportation
Command, to provide a report to the House Committee on Armed Services not later than April 15, 2020,
assessing the feasibility, affordability, and advisability of expanding the use of contractor-operated aerial
refueling aircraft to support Air Force receiver requirements.” The response was issued in April 2020. It
concluded that the Secretary of the Air Force “believes commercial contract air refueling is feasible if al
legal, policy and budgetary concerns are overcome.” It identified five options for structuring contract
aerial refueling, with different advantages, disadvantages, and timelines:
Government furnished equipment, in which contractors would operate Air Force aircraft.
Government sale or lease of surplus aircraft, where contractors would purchase retired
Air Force tankers.
Foreign government surplus tankers, with contractors owning and operating aircraft
formerly operated by other countries’ militaries.
Modification of existing commercial aircraft with a boom and associated air refueling
systems, converting civilian cargo jets to tankers, as used by the contractor Omega Air in
its work for the U.S. Navy.
Commercial off-the-shelf tanker, where contractors would purchase and operate new,
purpose-built tankers like the A330 MRTT and KC-46.
Overal , these changes to the Air Force’s tanker roadmap mean that the previous two-tanker fleet, which
was expected to evolve for a time to a single model, could eventual y become a three-tanker fleet (KC-46,
Bridge Tanker, and Advanced Air Refueling Tanker) plus whatever types contractors operate. This may
have implications for Air Force overhead spending, as each type w ould have unique parts and support
requirements. (The cost of maintaining the contracted aircraft would presumably be included in the
contract price.)
On December 12, 2019, the Air Force held an industry day, where interested vendors could offer briefings
on aerial refueling services and discuss requirements with military officials. A second industry day was
scheduled for a year later. An Air Force briefing about the program indicated a contract solicitation could
be expected in June 2020. That solicitation has yet to appear.
Realization of these new plans could affect whether, from where, and when new tankers are acquired; Air
Force personnel levels; the location and staffing levels of tanker bases; and the viability of private sector
service businesses going forward, among other issues.
Congressional Research Service
3
Author Information
Jeremiah Gertler
Specialist in Military Aviation
Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff
to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of
Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of
information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role.
CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United
States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However,
as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the
permission of the copyright holder if you wish to copy or otherwise use copyrighted material.
IN11537 · VERSION 2 · UPDATED