ecessary requirements for the entire alteration/repair. SYSTEMS DATA APPROVAL ONLY) PURPOSE OF DATA Substantiates cockpit and cabin modifications. Aircraft SM 5173 only. APPLICABLE REQUIREMENTS Wig specific sections) FAR 25.1301(a)(b)(c), 25.1309(b), 25.1351(a), 25.1 353(a), 25.1 352(a)(c)(dXe) and 25.143