Sir Donald Bailey, 83, inventor of the movable Bailey Bridge that played a key role in the Allied victory in World War II, died May 5 at a hospital in Bournemouth, England. The cause of death was not reported.

"Without the Bailey Bridge, we should not have won the war," Britain's Field Marshal Lord Bernard Law Montgomery once said. "It was the best thing in that line we ever had," he added.

The bridge was assembled from welded panels of light steel linked by pinned joints and stretched across pontoons. It could easily be carried by a few men and could hold loads weighing several tons. Used in the June 1944 Normandy landings, it carried Allied troops, tanks and guns over scores of rivers and gorges in Europe.

The Bailey Bridge was designed as a collapsible steel bridge, and its ease in construction meant not only that it could be moved quickly but also that if it was destroyed, it could be rebuilt or replaced in a matter of hours. It was superior to comparable American models. The bridge was popular with both American and British forces in Italy; it proved especially useful there because German forces came to rely on bridge demolition as a centerpiece of its tactical campaign in delaying the Allied advance.

Donald Coleman Bailey was born in Yorkshire, England, and spent much of his childhood making model bridges from pieces of wood and string. He sketched the original design for his famed bridge on the back of an envelope and took it to the British War Office, where it was accepted in 1941. He was paid a fee of 12,000 pounds -- then the equivalent of $48,000 -- for the invention.

Although Bailey was modest about his achievement, saying it was "just part of his job" as a civil engineer, he accepted a knighthood in 1946. A year later, the Inland Revenue refunded to him 5,400 pounds, or $21,600, which had been taken in taxes from his fee for designing the bridge.

Survivors include his wife, Mildred, and a son.