Obituary for Ralph A. Bagnold.

June 1, 1990
Ralph Bagnold, 94, Expert on Physics Of Sand in the Desert
AP

LEAD: Brig. Ralph Bagnold, an expert on the physics of desert sand and winds, died on Monday. He was 94 years old and had fought in both world wars.

Brig. Ralph Bagnold, an expert on the physics of desert sand and winds, died on Monday. He was 94 years old and had fought in both world wars.

In World War II, he formed and commanded the Long Range Desert Group in the Middle East and North Africa, where his previous research on the Libyan desert was said to be invaluable to British forces.

He wrote ''Libyan Sands,'' a chronicle of his pioneering desert trips, including the first 6,000-mile east-west crossing of the Libyan Desert. He also invented a compass for desert navigation.

Between the world wars, Ralph Bagnold returned to England and began his research, at the Imperial College in London, on the physics of sand movements. He wrote ''The Physics of Blown Sand and Desert Dunes,'' which has remained the standard textbook on the subject since its publication in 1941.

In 1970 the Geological Society of America awarded him its highest honor, the Penrose Medal, for his research on sand dune formations and movement.

Brigadier Bagnold's desert explorations and research contributed to NASA's understanding of the landscape of Mars. He was a consultant to the American Government on river problems and advised a number of oil companies on shock pressures exerted by sea waves on ships.

Brigadier Bagnold is survived by a son, Stephen, and a daughter, Jane. His wife, Dorothy Plank, died last year and his sister, Enid Bagnold, the author of ''National Velvet'' and other works, died in 1981