On display at the RSAF Museum. The TA-4S and TA-4S-1 were upgraded by Singapore Aircraft Industries (SAI) into the TA-4SU Super Skyhawk, of which the RSAF was the only operator of the type with its unique double cockpit arrangement. The two-seat Skyhawk trainer was combat capable. SAI replaced the Wright J65 turbojet with a non-afterburning GE F404 engine on RSAF Skyhawks during the upgrade.