If the proponents of remanufacturing need a defender, a protector, a champion, if they need a case-in-point that is unassailable, invincible, they need look no further than Boeing Military Airplane Co.'s B-52 bomber.

That monumental aircraft -- up to 488,000 pounds, with a wingspan of 185 feet -- was designed in the late 1940s and was first flown in 1952. The very last B-52 manufactured, a model H, rolled out of Boeing's Wichita plant on June 22, 1962. At the time of its inception, the bomber was slated to fly for about 10 years, then it would be replaced by a new generation of plane. Today, 22 years after the last of its breed came off the assembly line, 268 of the 742 B-52s manufactured still fly with the Strategic Air Command.

Remanufacturing gets the credit. The bomber's powerful J-57 turbojet and TF-33 turbofan engines are routinely remanufactured after about 4,000 flight hours, and its landing gears are reconstructed every four years. Originally conceived as a high-altitude, long-distance bomber, the B-52 has undergone modifications and improvements that have extended its range by some 65% while enabling it to maneuver at 500 feet or less. The priceless core -- an airframe that has recently been pushed to three design lifetimes in laboratory tests -- has been clipped, extended, reinforced, reconstructed, and upgraded with new technologies ranging from a "quick-start" feature to navigation and offensive avionics systems as advanced as those due to be employed on Rockwell International Corp.'s B-1B. The B-52, now being eyed for the Reagan Administration's Rapid Deployment Force, is expected to be flying through the year 2000.

All this is a temarkable achievement, and an unlikely prospect, for combat aircraft, most of which generally average about 3,000 hours in the air. The B-52D, when it was retired, had logged 13,000 flight hours, and the G's and H's still flying are now at about 10,000. Until the first operational B-1B is delivered in mid-1985, the remanufactured B-52 will remain a principal link of America's Triad, the combination of bombers, land-based missiles, and submarine-based missiles that constitutes the nation's strategic force.