Harrison was one of 76 German prisoners who tunneled out of Stalag Luft III in March 1944 but only three of the men managed to reach safety, The Times of London reports.
Their escape attempt was featured in the 1973 Hollywood blockbuster "The Great Escape" that starred Steve McQueen, Charles Bronson, James Garner and Richard Attenborough.
One of Harrison's Great Escape comrades, Alex Lees, died last year.
Harrison was working as a classics and Latin teacher in Sunderland when he was called up to serve as an RAF pilot.
"To others he was considered a war hero, but to us he was much more than that," said Harrison's son and daughter, Chris and Jane.