At least only one was blown over.
In Fort Hood, back in 1989, there were about a hundred blown over. I remember seeing pictures in the news of dozens of helicopters rolled over on their sides.
Ft. Hood Storm Damage $600 Million
L.A. TIMES ARCHIVES | MAY 20, 1989 12 AM PT | FROM ASSOCIATED PRESS
Storm damage to helicopters and buildings at the Army’s Ft. Hood outside Killeen, Tex., will cost at least $600 million to repair, the service said Friday. The Army said it had so far pegged last week’s storm damage to almost 200 helicopters at $585 million. Damage to buildings and other facilities was put at $15 million. Lt. Col. John Chapla, an Army spokesman, said exact repair figures are not available.
The storm, packing heavy rain and winds of 95 m.p.h., ravaged the area May 13. Although no one was killed, the storm forced 25 military families from their quarters and damaged the helicopters and at least 20% of the fort’s buildings. The damage occurred even though the Army said about half of the helicopters had been placed inside hangars as the storm approached and the remainder were tied down. Especially hard hit was the new fleet of AH-64 Apache attack helicopters. About 100 of the fort’s 150 Apaches were reported damaged, forcing the base to downgrade its state of aviation readiness.
Ft. Hood Storm Damage $600 Million - Los Angeles Times (latimes.com)