WASHINGTON — The Pentagon's annual spending on its long-range bomber fleet will rise to $11 billion over the next decade, a spike driven primarily by the updated cost estimate for Northrop Grumman to design and build the next-generation B-21.

The Pentagon’s 2016 annual aviation inventory and funding plan, which spans fiscal years 2017 through 2046, shows Air Force spending on long-range strike increases from about $5.5 billion now to about $11 billion in FY25 and FY26. This is a significant hike compared to the Pentagon’s 2015 plan, which showed the Air Force's spending on bomber reached its peak at about $9 billion around FY22, then slowed to just $7.5 billion in FY25.

The discrepancy is mainly due to the Air Force using an outdated B-21 cost estimate for the 2015 plan, according to service spokesman Maj. Rob Leese.

This is the first time the Pentagon has disclosed the long-term road map for its bomber fleet since the Air Force awarded Northrop the long-awaited contract to design and build the new B-21. The service announced the award Oct. 27, 2015, selecting the manufacturer of the B-2 stealth bomber over a team of Boeing and Lockheed Martin.

The Pentagon has not disclosed the full value of the engineering, manufacturing and development contract, but has said it includes $23.5 billion for the development phase as well as procurement of the first 21 bombers. When the effects of inflation, the cost to procure 100 planes at a target price of $564 million and other development costs are included, the Air Force's overall program cost could top $100 billion total in then-year dollars.

Also reflected in the new, long-term plan is the Air Force's decision to keep some legacy bombers in the fleet longer than expected due to the B-21's estimated delivery schedule, Leese said.

To support a bomber force structure that will include both the B-21 and some mix of legacy aircraft, the Air Force will invest in sustainment and modernization of the B-1, B-2 and B-52, according to the report.

"The adjustment to the current inventory of B-1, B-2 and B-52 continues to evolve as B-21 procurement estimates are included in the long-range strike inventory plan," Leese said.

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