While serving in the Royal Air Force in 1944, Rignold got the chance to conduct the Palestine Orchestra, now the Israel Philharmonic, and thereafter his career remained within the classical sphere. He was a staff conductor at the Royal Opera House, Covent Garden, 1947–1948; he directed the Liverpool Philharmonic (not then 'Royal') in the 1940s and 1950s, succeeding the popular Malcolm Sargent. A "period of unrest and strife" accompanied the beginning of Rignold's reign in Liverpool: Rignold replaced many older players in the orchestra, and some of the audience were unimpressed by his career in popular music.