A Balked landing is not a simple go around or missed approach landing. In a balked landing the airplane must be able to maintain a steady gradient of climb of at least (different for each airplane) with:
(1) Not more than the power that is available on each engine eight seconds after initiation of movement of the power controls from minimum flight-idle position;
(2) The landing gear extended;
(3) The wing flaps in the landing position; and
(4) A climb speed equal to VREF,
(1) Not more than the power that is available on each engine eight seconds after initiation of movement of the power controls from minimum flight-idle position;
(2) The landing gear extended;
(3) The wing flaps in the landing position; and
(4) A climb speed equal to VREF
Source: http://www.risingup.com/fars/info/part23-77-FAR.shtml