Asiana Flight 214 comes to mind.
One crew at my previous company nearly stalled a TCAS. Got an RA during descent, so TCS'd the aircraft to follow the RA. Didn't realise FLCH is SPDe not SPDt. Pithced up with autothrust commanding Idle.
After that, we were trained to fly FLCH with all automatics. If you want the AP out, change vertical mode first. I will be honest, it has caught me out once.