Army ponders Chinook replacement as upgrades continue.

• Author: Magnuson, Stew

The CH-47 Chinook, the helicopter that has in one version or another transported troops and cargo on battlefields for almost 50 years, may not end its production run until the end of the decade. And the F-models, which are produced at Boeing's Philadelphia factory, may be in service until 2040, or beyond. Yet the Army believes the time is now to begin looking at its future replacement.

"I used to kid all my Air Force buddies that we were going to keep the Chinook in service longer than the B-52," said Brig. Gen. William T. Crosby, program executive officer for Army aviation. "We're flying 70-year-old technology airframes and sustaining them effectively. That's a credit to the soldiers. But are we going to continue to sustain that for another 20 to 30 to 40 years? Or are we going to look for some new technology?" he asked at the Association of the United States Army aviation conference.

[ILLUSTRATION OMITTED]

While the Chinook first entered service in 1962, the twin-engine, twin-rotor design has its roots in World War II when the Navy was developing a tandem-rotor antisubmarine helicopter.

The airframe of the current models looks about the same as the first iterations of the aircraft introduced 49 years ago. Like the Air Force's long-range bomber the B-52, which has been flying since 1955, there have been several models with significant upgrades, though. Improvements continue to be planned for the Chinook even though it is still in the middle of its production run. Boeing has produced 115 F-models as of February, which is about halfway through its current contract, Pat Donnelly, Boeing's CH-47 domestic program manager, told National Defense.

A change in the way the airframe is put together may make them much more durable than the preceding models. The machined aluminum structure, which involves creating the fuselage out of a block of the metal, means there are roughly half the number of pieces and parts of previous models. This will result in less fatigue on the airframe, he said.

"It should be getting us a longer life," Donnelly said.

All the evidence is anecdotal so far, but reports from the field suggest that there is considerably less cracking and wear on the new airframes, he said. One unit has flown its F-models for more than 10,000 total hours, and has not reported any problems, he added.

"It's clearly more efficient from our perspective to assemble," Donnelly said. "But it's pretty much a wash as far as manufacturing costs." As for...