WASHINGTON — The U.S. Army has awarded Boeing a $391 million contract to build the first lot of five CH-47F Block II aircraft for the active force, as the service and the company continue to address technical issues with the program.

Boeing said earlier this year it was confident it would win a first production contract in fiscal 2021 to produce the latest variant of the cargo helicopters. The company said the program is still on track to deliver CH-47F Block II aircraft to the first Army unit in 2025.

Boeing is already in the midst of delivering the first of the special operations variant — the MH-47G. The contractor has 24 on order.

The Block II version features new rotor blades, fuel system and electrical system, and it has a stronger airframe that brings the Chinook up to a maximum gross weight of 54,000 pounds.

The contract kicks off a series of production purchases the Army did not want to make. The service proposed only buying G-model versions of the newest variant to free up funding for its future vertical lift endeavors.

But Congress disagreed.

In the FY21 budget, lawmakers funded five Block II variants for the active force. Both chambers indicated they would like to include funding in FY22 bills to buy more of the variant, but the defense policy and budget bills are yet to become law.

The Army originally planned to conduct a limited-user test in March 2021, but canceled it after testing in 2020 identified issues, including excessive vibration from the new Advanced Chinook Rotor Blades.

“The Army delayed execution of the CH-47F Block II Limited User Test (LUT), previously scheduled for March 2021, due to technical challenges,” the service said in a recent statement. “The Army is working with Boeing to address these technical challenges.”

A report from the Pentagon’s chief weapons tester noted the vibrations present in the ground, hover and forward flight could pose “safety of flight risk.” Boeing has maintained the problems are not safety issues.

“We’re working closely with the Army on a mitigation system or an adjustment to existing mitigation systems to account for that different vibration frequency,” Andy Builta, Boeing vice president and H-47 program manager, told Defense News earlier this year. “It is in no way a safety of flight risk, but it is an issue that needs to be addressed going forward.”

The company may adjust or add dampeners to address the problem.

“This is a low-risk, well-known activity that we’ve done across multiple platforms,” he noted.

Boeing also encountered problems with the fuel cell failing to self-seal in ballistic tests, but the firm is now testing a redesigned version at Aberdeen Proving Ground, Maryland.

The Block II variant returned to some testing this past spring and began to log flight hours again. The company proved the new variant’s rotor blades can handle an additional 2,500 pounds of lift, and the company continues to run ground tests on the new blades.

Jen Judson is an award-winning journalist covering land warfare for Defense News. She has also worked for Politico and Inside Defense. She holds a Master of Science degree in journalism from Boston University and a Bachelor of Arts degree from Kenyon College.

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