#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?i)_(Aircraft \w+?)_.+(\d{2}[a-z]{3}\d{4})-"
Local $sString = "__XXXXXXXX_XXX_XXXXXXX_XXXX_XXXXX_XXXX XXX_Aircraft 017_XXXXXXXX-XXXXXXX_XXXXXXX-XXXXXXX-XXXXXX-01Apr2021-XXXXX"
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYFULLMATCH)
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm