The PAF XT-004 Layang was a basic trainer aircraft developed by the Philippine Air Force's Air Force Research and Development Center (AFRDC).
After an intensified and revitalized self-reliance program in 1996, the XT-004 project, code-named "Layang", was developed by the PAFRDC in Villamor Air Base, Pasay. It is a single-engine aircraft powered by a 350 hp Allison Model 250-B17D turboshaft engine and is constructed from aluminum with a semi-monocoque structure. According to the PAFRDC, the aircraft jigs and fixtures have already been built since 1985, but lack of funds hindered the completion of the project.