AN EMS HELI PENETRATED CLASS B AIRSPACE WITHOUT ATC CLRNC BY 2 MI WHILE EVADING ANOTHER EMS HELI INBOUND TO THE LNDG ZONE THE RPTR JUST LEFT. FAR VIOLATION.

Narrative

THE LANDING ZONE; WHERE I PICKED UP A CRITICAL PATIENT; WAS LOCATED AT AN INTXN OF 2 ROADS AT THE SW CORNER OF ZZZ ARPT. I WAS MONITORING 122.7 FOR ZZZ ARPT; 123.05 FOR MY HOSPITAL DISPATCH AND ANOTHER EMS HELI INBOUND TO MY LOCATION; AND THE MEDICAL DISPATCH FREQ ON THE GND. I LIFTED OFF; CALLED ON 122.7; ZZZ UNICOM; AND STATED MY INTENTIONS TO FLY TOWARDS THE CTR OF THE ARPT AND THEN PROCEED E. AS SOON AS I CROSSED THE RWY EBOUND; I CHANGED MY RADIO FROM 122.7 TO 120.9 WITH INTENTIONS TO CALL ZZZ APCH BEFORE I ENTERED CLASS B AIRSPACE APPROX 2 MI TO THE E OF THE ZZZ ARPT. JUST AS I WAS ABOUT TO MAKE THE CALL; EMS Y HELI; (ANOTHER HELI HEADING FOR THE LNDG ZONE I JUST DEPARTED; AND COMING FROM THE DIRECTION I WAS GOING) CALLED AND ASKED FOR MY LOCATION AND ALT AS HE KNEW THAT WE WERE CLOSING ON EACH OTHER BUT HAD NOT MADE CONTACT. I IMMEDIATELY TOLD HIM WHERE I WAS AND AT WHAT ALT I WAS AT. I ALSO SPOTTED HIM AND TOLD HIM THAT I COULD MAINTAIN SEPARATION. AT ABOUT THE SAME TIME THAT I COMPLETED THAT CALL; I HEARD APCH CTL TELL EMS Y THAT I WAS AT HIS 12 O'CLOCK AND CLOSING. THE APCH CTLR THEN MADE A CALL TO ME; EMS X; AND INSTRUCTED ME TO REMAIN AT MY PRESENT ALT OR TURN TO AVOID EMS Y. I ACKNOWLEDGE THE CALL. THE CTLR THEN INFORMED ME THAT I HAD PENETRATED THE CLASS B AIRSPACE BY APPROX 2 MI AND THAT I SHOULD CALL BEFORE ENTERING. I ACKNOWLEDGE THE CALL. I INFORMED THE CTLR THAT I HAD EMS Y IN SIGHT.