INSIGHTi
B-52 Re-Engining Program Begins
Updated September 22, 2021
On May 19, 2020, the U.S. Air Force released a request for proposals to replace the TF33 engines
powering the B-52H Stratofortress bomber fleet with 608 new engines, in a contract running up to 17
years. The request does not give a dollar value for the contract, but the Air Force had previously estimated
the cost at $1.4 bil ion from FY2019 to FY2023. On September 21, 2021, service acquisition officials
announced that the contract would be awarded before October 2021.
The Air Force currently operates 76 B-52Hs, the most recent of which was built in the 1960s. The Air
Force now expects to operate them until 2050. The last TF33 engine was built in 1985. (For more on the
B-52 fleet, see CRS Report R43049, U.S. Air Force Bomber Sustainment and Modernization: Background
and Issues for Congress.)
Figure 1. Engine Mounting on B-52

Source: U.S. Air Force.
The re-engining effort (official y the Commercial Engine Replacement Program, or CERP) had been
anticipated for some time, as the Air Force had announced its plans to extend the B-52s’ service into at
least the 2040s, and had held an industry day on December 12, 2017, to share information and solicit
vendors for the program. Boeing, the B-52 prime contractor, even produced an animated video touting the
benefits of re-engining.
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The solicitation cal s for engines that are military-specific derivatives of existing commercial engines.
Given the specification that the eight engines on each B-52 were to be replaced by eight new engines (as
opposed to, perhaps, four larger engines), the expected candidates are variants of engines currently used
for business jets and regional airliners, as those best approximate the physical size of the TF33s to be
replaced while offering considerably improved fuel efficiency.
CERP’s principal goals are to reduce the fuel cost of operating the B-52 fleet while increasing reliability.
The engines under consideration provide similar thrust to the existing TF33s but are based on much more
recent designs. Also, as their commercial versions are in current service around the world, they can be
supported more easily using the commercial logistics infrastructure. Most commercial equivalents of the
TF33 have been retired, as have most TF33s used in other Air Force aircraft.
Potential vendors had already placed their candidate engines on display at public conferences, and are
believed to include
 GE Aviation (Evendale, OH), offering variants of the CF34 and Passport engines;
 Rolls-Royce (Indianapolis, IN) proposing a modified BR725;
 Pratt & Whitney (East Hartford, CT) with a militarized PW800.
Proposals are due to the Air Force by July 22, 2020, with the contract to be awarded in June 2021. Initial
engines are required to be delivered within 18 months of order.
The Air Force intends to award the indefinite delivery/indefinite quantity contract as a rapid prototyping
effort under what is known as Section 804 acquisition authority. Use of this authority had attracted
controversy among some Members of Congress. In the conference report accompanying the FY2020
National Defense Authorization Act (S. 1790), Congress required that the Air Force submit a report
detailing the acquisition and logistics strategies, key performance parameters, and other aspects of CERP,
and withheld 25% of the $175 mil ion pending release of that report. Although the Air Force has not
announced whether the report has been submitted, the CERP solicitation and its appendices include the
data requested in the NDAA conference report.
The competition is to be based on best value, with technical risk and price given approximately equal
weight. Specific evaluation factors are shown in Figure 2.

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Figure 2. Best Value Factors

Source: U.S. Air Force solicitation, “B-52 CERP Commercial Engine Replacement Program (CERP) Engine Contract,”
Appendix F, available at https://go.usa.gov/xwqey.


Author Information

Jeremiah Gertler

Specialist in Military Aviation




Disclaimer
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