HDG TRACK DEV BY A SINGLE PLT IN A VFR DHC6 DEP AFTER LOSING 2-WAY COM FOR A PERIOD OF TIME AT APA; CO.

Narrative

I WAS THE PIC; SINGLE PLT OF A DHC6 FLYING KAPA TO LONGMONT; CO (2V2). CONDITIONS WERE CAVOK; VFR. I WAS GIVEN THE CLRNC 'TWIN OTTER; NW DEP APPROVED; MAINTAIN RWY HDG; RWY 17L; CLRED FOR TKOF.' I ACKNOWLEDGED THE CLRNC BY READBACK. SHORTLY AFTER LIFTOFF; I HEARD AN ACFT CALL CENTENNIAL TWR TO RPT ESTABLISHED INBOUND ON THE ILS RWY 35R. A FEW SECONDS LATER; MY RADIO FAILED. I WAS UNABLE TO XMIT OR RECEIVE. BEING 'NO COM' AND KNOWING THERE WAS CONFLICTING TFC AHEAD; I BEGAN A SLOW; WIDE R TURN TO THE W ABOUT 1 MI S OF THE ARPT. I VISUALLY ACQUIRED A C172 BELOW AND BEHIND ME ALSO IN A R TURN AND MAINTAINED VISUAL SEPARATION. ABOUT 3 MINS LATER; THE RADIO CAME BACK ON AND TWR SAID; 'ACFT X WE'VE BEEN TRYING TO CALL YOU. YOUR CLRNC WAS RWY HDG AND YOU OVERFLEW A CESSNA TAKING OFF FROM RWY 17R. PLEASE CALL THE TWR ON A LANDLINE.' I CALLED AND SPOKE TO KAPA TWR SUPVR AND EXPLAINED. SHE SAID THEY WOULD HAVE PREFERRED ME TO CONTINUE RWY HDG AND THEY REALIZED I WAS NO COM. I BASED MY DECISION ON KNOWING THAT THEY CLRED ME FOR A NW DEP AND KNOWING OF CONFLICTING HEAD-ON TFC. CONTRIBUTING FACTORS WERE RADIO FAILURE; SINGLE PLT; COMPLEX ACFT; COMPLEX TFC ENVIRONMENT.