Claim: United Kingdom aircraft test serials include allocations A-Z then AB where is allocation is associated with a company and notes.
Evidence: A B C D E F G H I J J K L M N O P R S S T U V W X Y Y Z AB Slingsby Sailplanes Slingsby Aviation is a British aircraft company based in Kirkbymoorside, North Yorkshire, England. Replaced by G-26 in 1948