Joe Bertony, the engineer who invented the Sydney Opera House erection arch, which made the building of Sydney's most famous white sails possible, died on Sunday morning at his Hornsby home at the age of 97.

Corsican-born Mr Bertony's crucial contribution was the truss that supported the arches before each concrete segment was glued in place.

Opera House CEO Louise Herron and Joe Bertony, inventor of the Opera House erection arch at the building's 45th anniversary. Credit:Helen Pitt

He handwrote more than 30,000 separate mathematical equations to design the erection arch, which he gifted to the Museum of Applied Arts and Sciences (MAAS) and are now part of the Powerhouse Museum collection.

Before migrating to Australia in 1953, Corsican-born Mr Bertony, a French spy, twice escaped World War II concentration camps and was awarded France's Croix de Guerre.