 Since mid-1999, the A-4SU took on the additional role of being the designated advanced jet trainer (AJT) aircraft for the RSAF's AJT training program/detachment in Cazaux, France.Starting in 1973, the RSAF began to acquire Douglas A-4 Skyhawks.The first batch of over 50 airframes (ex-US Navy A-4Bs) was ordered and was subsequently requisitioned from the Military Aircraft Storage and Disposition Center (MASDC) at Davis–Monthan AFB, Arizona which was released to the Lockheed Aircraft Service (LAS) Company at Ontario, California, and its subsidiary Lockheed Aircraft Service Singapore (LASS) at Seletar Airfield, Singapore for a major overhaul and refurbishment.