Narrative:

While en route to ord from lga on J-36, we were cleared to dewit on the pullman arrival. We followed the omega heading and were subsequently told by ZOB to turn 5 degrees right for a better heading to dewit. He then stated that there must be a problem with S-80S because he always has to make similar course corrections on S-80S going to dewit in his sector. Sure enough -- his heading was right on. When crossing dewit, the omega showed that it would have taken us about 7 mi southwest of the actual fix had we used it for navigation. No conflicts or problems arose from this event, but it is interesting that center said he has to correct many of our S-80 flts. Dewit coordinates were properly loaded and checked on the omega. Callback conversation with reporter revealed the following information: the reporter has had no feedback from his air carrier on this incident other than acknowledgment of receipt of his report. He has also heard nothing from the FAA. The reporter believes that the ARTCC controller on duty that made the off course comment would be better able to comment on the frequency of this type of incident. The reporter understands that omega navigation works well for long range navigation, but that it can be quite imprecise when close to a VOR or a VOR/DME fix such as dewit.

Related reports:

Google
 

Original NASA ASRS Text

Title: TRACK DEV.

Narrative: WHILE ENRTE TO ORD FROM LGA ON J-36, WE WERE CLRED TO DEWIT ON THE PULLMAN ARR. WE FOLLOWED THE OMEGA HDG AND WERE SUBSEQUENTLY TOLD BY ZOB TO TURN 5 DEGS R FOR A BETTER HDG TO DEWIT. HE THEN STATED THAT THERE MUST BE A PROB WITH S-80S BECAUSE HE ALWAYS HAS TO MAKE SIMILAR COURSE CORRECTIONS ON S-80S GOING TO DEWIT IN HIS SECTOR. SURE ENOUGH -- HIS HDG WAS RIGHT ON. WHEN XING DEWIT, THE OMEGA SHOWED THAT IT WOULD HAVE TAKEN US ABOUT 7 MI SW OF THE ACTUAL FIX HAD WE USED IT FOR NAV. NO CONFLICTS OR PROBS AROSE FROM THIS EVENT, BUT IT IS INTERESTING THAT CTR SAID HE HAS TO CORRECT MANY OF OUR S-80 FLTS. DEWIT COORDINATES WERE PROPERLY LOADED AND CHKED ON THE OMEGA. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR HAS HAD NO FEEDBACK FROM HIS ACR ON THIS INCIDENT OTHER THAN ACKNOWLEDGMENT OF RECEIPT OF HIS RPT. HE HAS ALSO HEARD NOTHING FROM THE FAA. THE RPTR BELIEVES THAT THE ARTCC CTLR ON DUTY THAT MADE THE OFF COURSE COMMENT WOULD BE BETTER ABLE TO COMMENT ON THE FREQ OF THIS TYPE OF INCIDENT. THE RPTR UNDERSTANDS THAT OMEGA NAV WORKS WELL FOR LONG RANGE NAV, BUT THAT IT CAN BE QUITE IMPRECISE WHEN CLOSE TO A VOR OR A VOR/DME FIX SUCH AS DEWIT.

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.