In a small corner of the humongous 2020 U.S. Department of Defense (DOD) budget, among numerous procurement and upgrade projects, there’s notification that the DOD decided to halt the acquisition of the CH-47F Block II—the newest model of the venerable Chinook heavy-lift helicopter.

The decision indicates the end of an era for the Chinook, as the U.S. Army shifts its attention toward different projects. More specifically, the Army is experimenting with numerous programs under the Future Vertical Lift (FVL) project, which encompasses medium-lift, heavy-lift, unmanned, and reconnaissance rotary aircraft.

Quite reasonably, Boeing is opposed to the DOD decision, which hurts its operations. In a statement to Defense News, the defense industry behemoth said “delaying the CH-47 Block II production funding would have significant detrimental impacts for fleet readiness, the defense industrial base and taxpayers, and hamper soldiers’ abilities to carry critical payloads.”

Further, Boeing officials asserted that the impact of the Pentagon’s decision to halt the Block II program will be felt over the long term, given that the DOD doesn’t have a dedicated cargo-helicopter replacement project.

The weight of CH-47F Chinooks has gradually swelled because of the addition of protection systems. As a result, Boeing came up with the Block II upgrade, which includes numerous enhancements in survivability plus improved rotor blades and a better drive system. Overall, the Block II upgrade managed to shave off almost 4,000 pounds.

Before the 2020 DOD budget release, the plan was to procure 542 Block II Chinooks, divided to 473 F-models and 69 G-models. Now, however, the Army only gets the three CH-47F models and eight MH-47G machines already under construction.

The MH-47G is the special operations variant of the Chinook. It’s used by the 160th Special Operations Aviation Regiment (SOAR), also known as the Night Stalkers, and the British Joint Special Forces Aviation Wing.

In a 2016 interview with Defense News, Maj. Gen. William Gayler, commander of the Army Aviation Center of Excellence at Fort Rucker, discussed the topic of structural limitations within the available airframes. “I would argue that our current airframes have reached the feasible evolutionary limit to meet the Army Operating Concept,” he said. “We can certainly do things to make them go a little faster, make them stay a little longer, but not to the duration, range, or times we need to execute the Army Operating Concept.”

However, Major General Gayler added that the different versions of the Chinook helicopter are expected to stay in service at least until 2064.