Awww...we're off. I just rewatched "A Prime Problem" and indeed, Windcharger is knocked off a cliff and into a chasm. But he doesn't hit the edge and lose an arm! The specific memory I have, and I only remember a RED Autobot, is that he is hit directly in the chest with lasers and knocked backwards over a cliff. He hits a ledge halfway down, and it breaks his arm off. He bounces and falls the rest of the way landing hard on the ground at the bottom, gets up, picks up his arm, and snaps it back into place like nothing. It's such a violent moment! That especially in a 1980's cartoon was so shocking. Damn if I remember which Autobot or which episode though!