Narrative:

Departed abilene, tx, on an IFR flight plan. WX good with 9000' broken to overcast until san antonio, then low overcast until beeville NAS area at which time 1300' set. Most of flight conducted at 11000' VFR WX, good flight conditions. However, during this flight my newly installed LORAN needed 'position initialization,' repeating what had occurred on a similar night flight 48 hours previously from corpus to abilene. Generally, position initialization is required only upon initial installation of LORAN unit, or if LORAN is moved a considerable distance in off position or failure of LORAN navigation station. This was the third time this had occurred in 2 weeks. Although WX had improved to VFR conditions, I elected to continue my IFR approach to crp, and was cleared for NDB 13 approach after aimee intersection at 2000'. Several mins (1-2?), I was told I had passed this intersection by about 5 mi and given a vector back to conner NDB, which I accomplished and landed west/O problems after satisfactorily completing this approach as published. Although I was using the LORAN for backup navigation only, it has a memory database with all intxns, VOR's, etc. I was puzzled at the inaccuracy of this state of the art unit and why after landing at corpus it gave a position 5 mi away. After landing I visited the avionics shop on the field and discussed this with the manager, who told me it was his common knowledge that the dea (drug enforcement agency) was purposefully and routinely interfering with the raymondville master station on the southeast LORAN chain by jamming its xmissions in order to befuddle low flying drug smugglers who routinely use LORAN to navigation. He suggested I use the great lakes navigation chain. I find this dea practice dangerous and unacceptable and strongly protest it, as this example of the confusion it can cause is obvious.

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Original NASA ASRS Text

Title: NDB APCH LORAN GAVE POSITION AS 5 MI FROM FIX. POSSIBLE LORAN STATION INTERFERENCE.

Narrative: DEPARTED ABILENE, TX, ON AN IFR FLT PLAN. WX GOOD WITH 9000' BROKEN TO OVCST UNTIL SAN ANTONIO, THEN LOW OVCST UNTIL BEEVILLE NAS AREA AT WHICH TIME 1300' SET. MOST OF FLT CONDUCTED AT 11000' VFR WX, GOOD FLT CONDITIONS. HOWEVER, DURING THIS FLT MY NEWLY INSTALLED LORAN NEEDED 'POS INITIALIZATION,' REPEATING WHAT HAD OCCURRED ON A SIMILAR NIGHT FLT 48 HRS PREVIOUSLY FROM CORPUS TO ABILENE. GENERALLY, POS INITIALIZATION IS REQUIRED ONLY UPON INITIAL INSTALLATION OF LORAN UNIT, OR IF LORAN IS MOVED A CONSIDERABLE DISTANCE IN OFF POS OR FAILURE OF LORAN NAV STATION. THIS WAS THE THIRD TIME THIS HAD OCCURRED IN 2 WKS. ALTHOUGH WX HAD IMPROVED TO VFR CONDITIONS, I ELECTED TO CONTINUE MY IFR APCH TO CRP, AND WAS CLRED FOR NDB 13 APCH AFTER AIMEE INTXN AT 2000'. SEVERAL MINS (1-2?), I WAS TOLD I HAD PASSED THIS INTXN BY ABOUT 5 MI AND GIVEN A VECTOR BACK TO CONNER NDB, WHICH I ACCOMPLISHED AND LANDED W/O PROBS AFTER SATISFACTORILY COMPLETING THIS APCH AS PUBLISHED. ALTHOUGH I WAS USING THE LORAN FOR BACKUP NAV ONLY, IT HAS A MEMORY DATABASE WITH ALL INTXNS, VOR'S, ETC. I WAS PUZZLED AT THE INACCURACY OF THIS STATE OF THE ART UNIT AND WHY AFTER LNDG AT CORPUS IT GAVE A POS 5 MI AWAY. AFTER LNDG I VISITED THE AVIONICS SHOP ON THE FIELD AND DISCUSSED THIS WITH THE MGR, WHO TOLD ME IT WAS HIS COMMON KNOWLEDGE THAT THE DEA (DRUG ENFORCEMENT AGENCY) WAS PURPOSEFULLY AND ROUTINELY INTERFERING WITH THE RAYMONDVILLE MASTER STATION ON THE SE LORAN CHAIN BY JAMMING ITS XMISSIONS IN ORDER TO BEFUDDLE LOW FLYING DRUG SMUGGLERS WHO ROUTINELY USE LORAN TO NAV. HE SUGGESTED I USE THE GREAT LAKES NAV CHAIN. I FIND THIS DEA PRACTICE DANGEROUS AND UNACCEPTABLE AND STRONGLY PROTEST IT, AS THIS EXAMPLE OF THE CONFUSION IT CAN CAUSE IS OBVIOUS.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.