Board Thread:General Discussion/@comment-24584493-20140225081826/@comment-88.0.136.7-20140225143223

IIRC the empty boxes in the end of some aircraft family's were there because they didn't wanted to cut any family, and the empty boxes after the ADF-01 are for the ADA-01 as Generale wareagle said AND for keeping the "thing" (I don't remember how it was called) looking like a rectangle.