Airworthiness Directives; BLANIK LIMITED Gliders

We are superseding airworthiness directive (AD) 2000-20-11 for BLANIK LIMITED Models L-13 Blanik and L-13 AC Blanik gliders (type certificate previously held by LET Aeronautical Works). This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as insufficient material strength of the tail-fuselage attachment fitting. We are issuing this AD to require actions to address the unsafe condition on these products.