SMA PLT RELYING ON LORAN NAV. EQUIP GOES BERSERK; RECEIVES VECTOR FROM TRACON.

Narrative

FLT WAS PLANNED FROM WESTERN LA; TO LAKELAND; FL; NON- STOP; APPROX 600 STATUTE MI. HOWEVER; THE QUARTERING HEADWINDS ENCOUNTERED FOR MOST OF THE DISTANCE TRAVELED MADE FOLLOWING THE COASTLINE A MUCH SLOWER FLT AND ADDITIONAL FUEL BURN OBSERVED AT 1/2 WAY POINT WAS NOTED. WE PLUGGED IN THE LORAN C UNIT TO LAKELAND AND KEPT THE NEEDLE CTRED. WE FLEW ON TOP OF SCATTERED CLOUDS; TOPS ABOUT 3100 FT. DIRECTIONAL AND ALT CHANGES WERE REQUESTED BY FLT FOLLOWING AS WE TRANSVERSED PAST MOBILE; PENSACOLA; EGLIN; AND TYNDALL RADARS. RESULT WAS ARR NEAR LAKELAND WITH MINIMAL FUEL REMAINING. SUDDENLY THE LORAN WENT BESERK. IT WAS WAY OFF ON ITS READINGS AND WE RECHKED OUR POS ON THE MAPS. LORAN SHOWED LAKELAND 1.5 MI STRAIGHT AHEAD; BUT NO ARPT ANYWHERE IN SIGHT AS WE CIRCLED. HAD TO REQUEST A STEER FROM TAMPA APCH. TO LOCATE THE NEAREST ARPT (BARTOW) AS FUEL WAS LESS THAN WE HAD ANTICIPATED ON ARR IN THE AREA. THE LORAN HAD PREVARICATED TO US; FOR REASONS UNKNOWN. WE HAD BYPASSED E OF LAKELAND ARPT WITHOUT SEEING THE ARPT; BUT LORAN INDICATED LAKELAND ARPT WAS MUCH FURTHER S. CONCLUSION IS LORANS MUST BE SUBJECT TO ERRORS OF CONSIDERABLE MAGNITUDE; AND MAY NOT BE VERY RELIABLE; UNDER SOME CONDITIONS.