 The heavily armed WA @-@ 116 <unk> " Little Nellie " was included after Ken Adam heard a radio interview with its inventor , RAF Wing Commander Ken Wallis . Little Nellie was named after music hall star Nellie Wallace , who has a similar surname to its inventor . Wallis <unk> his invention , which was equipped with various mock @-@ up <unk> by John <unk> ' special effects team , during production . 
