NMAC.

Narrative

I WAS PLT OF A HELI THAT WAS INVOLVED IN A NEAR COLLISION WITH A JET. NO PERSONS WERE INJURED AND NEITHER ACFT RECEIVED ANY DAMAGE. I DID NOT HAVE TO PERFORM EVASIVE MANEUVERS. THE WX THAT DAY WAS SUNNY AND CLR. THE GND WAS SNOW-COVERED. SNOW FROM THE RWYS WAS PILED UP AT THE EDGES OF THE RWY AFTER BEING CLRED. TO THE BEST OF MY KNOWLEDGE; THESE ARE THE CIRCUMSTANCES LEADING UP TO THE EVENT. I WAS PERFORMING ROUTINE TFC PATTERNS FROM THE DESIGNATED HELI TKOF AND LNDG AREA; NEAR THE END OF RWY 23. THE ACTIVE RWY WAS 30 AND FIXED WING TFC WAS FLYING L-HAND TFC. IN THIS CONFIGN; HELI TFC HAS BEEN INSTRUCTED TO FLY FROM THIS SPOT AND TO PERFORM L-HAND PATTERNS. THIS PATTERN REQUIRES XING THE MAIN ILS RWY; 23-5; AS WELL AS INTEGRATING INTO THE FIXED WING PATTERNS. AS INSTRUCTED; I PERFORMED A CLRING TURN TO DETERMINE THE LOCATIONS OF ANY ACFT. I IDENTED 3 ACFT; 2 FIXED WING AND 1 ROTOR WING CRAFT IN THE PATTERN. OF THE FIXED WING ACFT; 1 WAS ON BASE AND 1 WAS ON FINAL. THE OTHER HELI WAS ON FINAL TO THE R OF RWY 30. THE RADIO TFC CONFIRMED THESE ACFT POS. FREDERICK UNICOM ALSO ASKED AN ACFT WHAT ITS DEST WAS AND THE REPLY WAS 'WE'RE GOING TO WINCHESTER.' IMMEDIATELY PRIOR TO TKOF; I ANNOUNCED MY INTENTIONS OVER THE CTAF 123.00. CLRLY STATING THAT I WAS TO THE L OF RWY 30 AND THAT I WOULD BE PERFORMING A L- HAND TFC PATTERN. AS I PROGRESSED IN MY TKOF; I SAW A JET TAKING OFF FROM RWY 23. OUR PATHS CROSSED; WITH THE JET FLYING AN ESTIMATED 50 FT IN FRONT AND OVERHEAD. BY THE TIME WE SAW EACH OTHER; THERE WAS NO TIME TO ALTER OUR COURSES. THE JET CONTINUED ON IN ITS FLT AND I LANDED. THE ENTIRE EVENT WAS DISCUSSED WITH MY INSTRUCTOR. THIS SCENARIO HAS BEEN CONFIRMED WITH THE PLT OF THE OTHER HELI. SEVERAL FACTORS CONTRIBUTED TO THIS NEAR COLLISION. FIRST; AND FOREMOST; THE TFC PATTERN CONFIGN REQUIRES THAT HELIS CROSS AN ILS RWY; FREQUENTLY USED BY JET TFC; NO MATTER WHAT THE ACTIVE RWY IS. THE ACTIVE RWY; AS ANNOUNCED BY FREDERICK UNICOM WAS 30. THE JET TOOK OFF FROM RWY 23. ALTHOUGH IT IS THE PLT'S PREROGATIVE TO USE ANY RWY; USING XING RWYS AT THIS BUSY TRAINING ARPT CAN BE CONFUSING. ADDITIONALLY; WITH ALL THE AIR TFC AT THIS ARPT; IT IS DIFFICULT TO DETERMINE IF TFC IS INBOUND ON THE ILS.