C_star, MD83, Fly3
Even before this MOD there was protection but it was through mode reversion, if excessive VS was selected in climb when speed reached VLS a mode reversion used to take place. From Speed/VS the FMGC/FD used to change to THR CLB/OP CLB similarly in descent from Speed/VS it used to change to THR IDL/OP DES. With this MOD the mode reversion doesn't take place instead the VS is boxed flashing amber and the AP temporarily abandons the target VS and automatically reduces the VS to maintain the VLS.