[PAR35]

The world's oldest aircraft carrier INS Viraat

Not accurate as written. Perhaps the 'oldest operational aircraft carrier'. The Yorktown is older.

Hermes - laid down 1944, launched 1953, commissioned 1959 (union labor)
Yorktown - laid down 1941, launched 1943, commissioned 1943

[Steven Scharf]

As per wiki the was 1924 HMS Hermes which was one of the first aircraft carrier.

The advent of fixed-wing aircraft in 1903 was followed in 1910 by the first flight from the deck of a US Navy cruiser. Seaplanes and seaplane tender support ships, such as HMS Engadine, followed. The development of flat top vessels produced the first large fleet ships. This evolution was well underway by the early to mid-1920s, resulting in the commissioning of ships such as Hōshō (1922), HMS Hermes (1924),[1] Béarn (1927), and the Lexington-class aircraft carriers (1927).