LGT HAS 2 SUCCESSIVE ENG FIRE WARNINGS. RETURNS TO DEP ARPT ONCE.

Narrative

ON DEP FROM MONTEREY GOING THROUGH 1000 FT AGL; WE EXPERIENCED A BRIEF FIRE WARNING ON THE #3 ENG. THE COPLT WAS FLYING AND HAD JUST CALLED FOR FLAPS 2; CLB PWR. HE PULLED THE THROTTLES BACK A LITTLE AND THE FIRE WARNING STOPPED. A SCAN OF THE ENG INSTS SHOWED EVERYTHING WAS NORMAL. I MADE THE DECISION TO RETURN TO THE ARPT AND HAVE THE ENG LOOKED AT. MAINT AT MONTEREY FOUND A LOOSE FITTING AND FIXED IT. WE DID 2 ENG RUN-UPS. BOTH WERE NORMAL. WE TOOK OFF AGAIN AT XA18. AT APPROX 9000 FT MSL WE EXPERIENCED THE SAME BRIEF FIRE WARNING. WE CALLED TULSA TECHNICIANS AND THEY SAID WE HAD A CROSS-OVER BLEED LEAK. THEY SAID THAT IT WAS PERFECTLY SAFE TO BRING THE ACFT TO DFW USING REDUCED PWR ON THE #3 ENG. WE FLEW ON TO DFW AND LANDED WITH NO FURTHER PROBS. SUPPLEMENTAL INFORMATION FROM ACN 243442: WHEN THE CHKLIST CALLED FOR SECURING THE ENG; THE CAPT REFRAINED; STATING THAT WE PROBABLY HAD A FALSE INDICATION AND WANTED TO KEEP ENG IN IDLE SINCE WE WERE IN MOUNTAINOUS TERRAIN AT NIGHT. WE IMMEDIATELY RETURNED TO MONTEREY. TOOK OFF AGAIN. THIS TIME AT ABOUT 9000 FT AGL THE SAME FIRE WARNING OCCURRED. AGAIN; THE CAPT ELECTED NOT TO SECURE #3 ENG; BUT LEFT IT AT IDLE. WE RETURNED TO MONTEREY AND ORBITED OVER THE FIELD WHILE WE TALKED TO BOTH MAINT AND DISPATCH. MAINT SUGGESTED WE GO ON TO DFW; WITH ENG AT IDLE; AS A SAFE PROC.