Revision of F3153-15 Standard Specification for Verification of Avionics systems; continued evolution of this standard. This specification was originally conceived to provide guidance to avionics system manufactures intended for LSA and experimental applications. This standard has been found to be more broadly applicable in its usage but lacks detailed criteria that can be helpful in obtaining approval by CAA regulatory bodies for low end certified aircraft. The intent is to add material to better define acceptance criteria and capture concerns from both manufactures and CAA bodies. This standard will provide for a simplified method of showing system verification to meet the compliance for safety and intended functions.