After 50 years, there is no end in sight for the Chinook.

• Author: Magnuson, Stew
• Position: Aviation - Geographic overview

RIDLEY TOWNSHIP, Pa.--The Army recently sent a circa 1968 CH-47 Chinook to this sprawling helicopter factory along the banks of the Delaware River to have it refurbished so it can again be dispatched on missions.

April will mark the 50th anniversary of when the service received the first delivery of the twin-rotor, heavy-lift chopper. And of all the aircraft its manufacturer The Boeing Co. has produced since 1910, the Chinook is by far the company's longest lasting, and most enduring product.

So, how much longer can U.S. troops expect to look at the sky and see the familiar silhouette of a Chinook flying by?

Consider that the new F-model, which was introduced in 2007, will not replace all its D-model predecessors until 2019 or 2020, said J. Patrick Donnelly, Chinook program manager at Boeing. The best estimate for when an Army program that would introduce a new heavy lift helicopter will come to fruition is about 2030. But it takes about 14 years to swap one model's inventory out for another.

"That leaves them around to 2040 to 2050 without batting an eye. So that puts us at 90 years, and it's anyone's speculation as to what happens" after that, Donnelly said.

Boeing clearly believes in the Chinook's long-term future. It was putting the finishing touches on a $130 million project to modernize its factory here in the Philadelphia outskirts. All that remained were some new classrooms and remodeled cafeterias for the wrorkers.

The Army has a nascent program called Future Vertical Lift, formerly known as the Joint Multirole Helicopter. When, and if, that gets going in earnest remains to be seen. The Obama administration's fiscal year 2013 budget proposal calls for Army aviation modernization programs to be pushed back by two years.

Meanwhile, the Chinook remains a popular export. Twenty nations currently have them in their inventories. Foreign sales could keep the line going after the U.S. Army finds a replacement some two decades from now.

"My goal is to keep the Chinook technically relevant until its time is up," Donnelly said.

One of the improvements is a new rotor blade, which the Army and company officials hope will add 1,500 pounds--and possibly up to a ton--of new lift capability.

The program just finished its critical design review, and Boeing will begin to produce the improved blades for more extensive testing. The last time the Chinook had new blades was 1980 when composite materials replaced metal, Donnelly said.

A platitude often...