This change was dated March 10, 1986, and the type certificate declared that although the MD designator could be used in parentheses, it must be accompanied by the official designation, for example: DC-9-81 (MD-81).
Este cambio produciuse o 10 de marzo de 1986, e a certificación declarou que aínda que podía usarse a designación MD entre paréntese, este debía estar acompañada pola oficial, por exemplo: DC-9-81 (MD-81).