Boeing has started development of a Block 2 upgrade of the U.S. Army’s CH-47 Chinook heavy-lift helicopter. Plans call for delivering 542 upgraded helicopters from 2023 into the 2040s.
Block 2 Chinooks will be retrofitted from current CH-47F and special operations MH-47G models, numbering 473 and 69 airframes, respectively. The upgrade introduces new advanced design composite rotor blades, an improved drive train, single (as opposed to segmented) sponson fuel tanks and strengthened aft, pylon and nose sections.

The Army granted the program Milestone B approval to move from technology maturation to engineering and manufacturing development (EMD) on April 5. Boeing will build and test three prototypes under the EMD phase; it expects the Army will make a Milestone C decision to begin low-rate initial production (LRIP) in 2021, with first deliveries following in 2023.

The Block 2 upgrade follows an evolutionary path that envisions the workhorse helicopter operating into the 2060s, Boeing Defense executives said May 18 during a media visit the company hosted at its Ridley Park, Pennsylvania manufacturing facility, wher Chinooks are assembled. Block 2 does not come with a new engine to replac the Chinook’s twin Honeywell Lycoming T55-GA-714A turboshafts, which would likely feature in a Block 3 upgrade. The new powerplant would stem from the Army’s Future Affordable Turbine Engine (FATE) program to design a 5,000- to 10,000-shp class turboshaft engine.

If the Army intends to operate the Chinook into the 2060s, a Block 3 upgrade will be necessary and “it has to start with the engine,” said Randy Rotte, Boeing director of Chinook global sales and marketing. The “decision point” for the next upgrade will be sometime between 2023 and 2032, he added.

CH-47F maximum gross weight will increase from 50,000 pounds to 54,000 pounds (with payload increasing from 19,278 pounds to 22,207 pounds) under the Block 2 upgrade, matching the weight of G models and allowing for the interchange of common parts, Rotte said. The increased weight is supported by the new swept-tip, anhedral Advanced Chinook Rotor Blades, which provide 1,500 pounds greater lift capacity, plus structural modifications and a higher-rated drive train.

Boeing expects to sign an EMD contract to begin Block 2 work within months. The first F-model helicopter will be disassembled by Summit Aviation, based in Middletown, Delaware, then sent to Ridley Park for the upgrade.

Meanwhile, Boeing is competing to provide the CH-47F to Germany, which has a requirement for 40 to 60 helicopters to replac its current fleet of CH-53 heavy-lift helicopters. The Chinook is poised against the Lockheed Martin/Sikorsky CH-53K, “our first head-to-head competition in quite a while,” Rotte remarked. Boeing is also responding to questions regarding Israel’s CH-53 replacement requirement, he said.