Narrative:

This is not the first time omega has let me down. With GPS, IRS, INS it is incredulous that the FAA still lets airlines use this antiquated electronic navigation equipment. X- checked and programmed omegas by company policy. Departed runway 12 at bda and cleared left on course direct gabes (waypoint #1). After track change update proceeded direct gabes on 317 degrees. Engaged autoplt passing 5000 ft and selected auxiliary navigation. Crossed waypoint #1 (gabes) at H plus 57Z in radar contact. Verified position with bda center and omegas. Continued on filed flight plan and contacted ny arinc with position report. They advised crossing daner (waypoint #2) contact center on 132.15. Upon reaching daner, attempted to contact center, but was unable, due to radio congestion until 50 mi from daner. Center requested position report over champ (waypoint #3). Upon reaching waypoint #3 (as shown by omegas), contacted ZNY with position report. Center advised us, after requesting identify, that we were not in radar contact (over champ). Then we were given frequency change to washington 124.72. Washington established radar contact with us 120 mi wsw of champ (we verified this position by requesting our present position in latitude and longitude coordinates, then plotted the position on the caribbean plotting chart -- we agreed that we were southwest of champ. However, omegas verified present position over champ. We then froze present position (hold and plotted coordinates. Our present position was 85 mi from ZDC radar fix. We advised center of unreliable omegas at this time received IFR clearance to baltimore. Callback conversation with reporter revealed the following information: the reporting captain states that he had the same aircraft 1 week later, phl-sju. ARTCC caught him in a track error as he was entering the oceanic portion of his trip. He reverted to VOR airways and had to land at clt for fuel. This caught the company's attention to the point that they took this aircraft off of overwater flying for a month in an attempt to find and rectify the problem the maintenance people described this situation as an 'insidious' error. Both of this reporter's incidents , and 2 others that the same air carrier had, were during times of very high x-track winds in hurricane influenced conditions. Both omega sets told the same lies and worked fine after updating over orf. There has been no mention of certificate action. The reporting first officer flew this same aircraft over land on 2 separate occasions. The crew was to evaluate the omega performance in both cases, the crew refused to clear the aircraft for overwater flight as the omega system failed to track properly.

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Original NASA ASRS Text

Title: AN OMEGA EQUIPPED LGT ACR ACFT HAD A GROSS NAV ERROR BTWN BDA AND BWI. THERE WERE HURRICANE FORCE XTRACK WINDS AT THE TIME.

Narrative: THIS IS NOT THE FIRST TIME OMEGA HAS LET ME DOWN. WITH GPS, IRS, INS IT IS INCREDULOUS THAT THE FAA STILL LETS AIRLINES USE THIS ANTIQUATED ELECTRONIC NAV EQUIP. X- CHKED AND PROGRAMMED OMEGAS BY COMPANY POLICY. DEPARTED RWY 12 AT BDA AND CLRED L ON COURSE DIRECT GABES (WAYPOINT #1). AFTER TRACK CHANGE UPDATE PROCEEDED DIRECT GABES ON 317 DEGS. ENGAGED AUTOPLT PASSING 5000 FT AND SELECTED AUX NAV. CROSSED WAYPOINT #1 (GABES) AT H PLUS 57Z IN RADAR CONTACT. VERIFIED POS WITH BDA CTR AND OMEGAS. CONTINUED ON FILED FLT PLAN AND CONTACTED NY ARINC WITH POS RPT. THEY ADVISED XING DANER (WAYPOINT #2) CONTACT CTR ON 132.15. UPON REACHING DANER, ATTEMPTED TO CONTACT CTR, BUT WAS UNABLE, DUE TO RADIO CONGESTION UNTIL 50 MI FROM DANER. CTR REQUESTED POS RPT OVER CHAMP (WAYPOINT #3). UPON REACHING WAYPOINT #3 (AS SHOWN BY OMEGAS), CONTACTED ZNY WITH POS RPT. CTR ADVISED US, AFTER REQUESTING IDENT, THAT WE WERE NOT IN RADAR CONTACT (OVER CHAMP). THEN WE WERE GIVEN FREQ CHANGE TO WASHINGTON 124.72. WASHINGTON ESTABLISHED RADAR CONTACT WITH US 120 MI WSW OF CHAMP (WE VERIFIED THIS POS BY REQUESTING OUR PRESENT POS IN LATITUDE AND LONGITUDE COORDINATES, THEN PLOTTED THE POS ON THE CARIBBEAN PLOTTING CHART -- WE AGREED THAT WE WERE SW OF CHAMP. HOWEVER, OMEGAS VERIFIED PRESENT POS OVER CHAMP. WE THEN FROZE PRESENT POS (HOLD AND PLOTTED COORDINATES. OUR PRESENT POS WAS 85 MI FROM ZDC RADAR FIX. WE ADVISED CTR OF UNRELIABLE OMEGAS AT THIS TIME RECEIVED IFR CLRNC TO BALTIMORE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTING CAPT STATES THAT HE HAD THE SAME ACFT 1 WK LATER, PHL-SJU. ARTCC CAUGHT HIM IN A TRACK ERROR AS HE WAS ENTERING THE OCEANIC PORTION OF HIS TRIP. HE REVERTED TO VOR AIRWAYS AND HAD TO LAND AT CLT FOR FUEL. THIS CAUGHT THE COMPANY'S ATTN TO THE POINT THAT THEY TOOK THIS ACFT OFF OF OVERWATER FLYING FOR A MONTH IN AN ATTEMPT TO FIND AND RECTIFY THE PROBLEM THE MAINT PEOPLE DESCRIBED THIS SITUATION AS AN 'INSIDIOUS' ERROR. BOTH OF THIS RPTR'S INCIDENTS , AND 2 OTHERS THAT THE SAME ACR HAD, WERE DURING TIMES OF VERY HIGH X-TRACK WINDS IN HURRICANE INFLUENCED CONDITIONS. BOTH OMEGA SETS TOLD THE SAME LIES AND WORKED FINE AFTER UPDATING OVER ORF. THERE HAS BEEN NO MENTION OF CERTIFICATE ACTION. THE RPTING FO FLEW THIS SAME ACFT OVER LAND ON 2 SEPARATE OCCASIONS. THE CREW WAS TO EVALUATE THE OMEGA PERFORMANCE IN BOTH CASES, THE CREW REFUSED TO CLR THE ACFT FOR OVERWATER FLT AS THE OMEGA SYS FAILED TO TRACK PROPERLY.

Data retrieved from NASA's ASRS site as of July 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.