Combined tip flag blade core

An airfoil for a gas turbine engine, the airfoil configured to extend in a radial direction relative to an engine axis from an inner diameter to an outer diameter and comprising:

• a body having a base disposed at the inner diameter, a tip disposed at the outer diameter, a leading edge, a trailing edge, a pressure side wall extending between the leading edge and the trailing edge and between the base and the tip, and a suction side wall extending between the leading edge and the trailing edge and between the base and the tip;
• and
• a cooling circuit disposed in the body, the cooling circuit comprising:
• a serpentine channel having a plurality of radially extending passages connected in flow series from a first passage to a final passage, wherein the first passage is fluidly connected to a first inlet;
• a tip flag channel disposed adjacent to the serpentine channel, the tip flag channel comprising:
• a first tip flag passage extending radially and disposed immediately adjacent to the final passage of the serpentine channel, wherein a first wall separates a full radial extent of the final passage from the first tip flag passage, and wherein the first tip flag passage is fluidly connected to a second inlet, the second inlet separated from the first inlet by a second wall;
• a second tip flag passage disposed between the serpentine channel and the tip, the second tip flag passage extending axially from the first tip flag passage and in direct fluid communication with each of the first tip flag passage and the final passage of the serpentine channel;
• and
• a metering orifice fluidly connecting the first tip flag passage and the second tip flag passage, the metering orifice having a cross-sectional area less than a cross-sectional area of each of the first tip flag passage and the second tip flag passage and wherein the cross-sectional area of the metering orifice is selected to reduce a pressure of a fluid flow exiting the first tip flag passage to a value equal to or less than a pressure of a fluid exiting the final passage of the serpentine channel such that a cooling fluid is prevented from being ingested by the serpentine channel at an outlet of the final passage.