On November 1, 1962, fifty R17s (numbers 6500–6549) were transferred from the Mainline IRT to the 7, allowing for ten-car operation. This was the first time that the IRT ran ten-car trains without a second conductor. With the 1964–1965 World's Fair in Flushing Meadows–Corona Park in April 1964, trains were lengthened to eleven cars. The Flushing Line received 430 new R33 and R36 "World's Fair" cars for this enhanced service.