It was 2-0 just moments later after the half-time though, when Liverpool's goalie Aroon Clansey rushed from her line to deny Carney, only to see her header fall to Isobel Christiansen, who showed terrific instincts to volley into the unguarded net from around 35 yards out.
An eventful start produced more drama shortly afterwards the opener, when Carney's goal-bound corner was handled on the line by Bristol Academy's Alex Culvin, leaving the referee no option but to brandish a red card.
With David Parker's side firmly in the ascendancy, there was little action to speak of in the remainder of the first-half, that was until Carney bagged two quick fire braces shortly before the break.
Mark Sampson's team grabbed a consolation courtesy of Laura del Río's strike late on, but this couldn’t take the gloss off a memorable day for the Ladies, but Birmingham secure their place in the final for the first time in the FA Women's Cup history.
From Sophie Ingle's corner kick, her high delivery was met at the far post by Gemma Bonner, who prodded home from a yard out to give Chelsea the advantage.
From Danielle Buet's delivery, Bonner flicked onto Susi, who was not to be denied, meeting the ball with a powerful header into the top corner to secure Chelsea's place in the final four with a 2-0 win.
Stand-in skipper Susi almost doubled the Blues' advantage after racing clear to meet Dani Buet's through-ball, forcing Emma Byrne into a low save, and Chelsea also secure their place in the final for the first time in the FA Women's Cup history.
The Londoners retook the lead in the first half of extra time through substitute Kate Longhurst, but the Blues bounced back once more when Carney converted a centrally-placed free-kick on the edge of the box.