|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Locale Reference||navaid : fmn.vortac|
|Operator||common carrier : air carrier|
|Make Model Name||Beech 1900|
|Operating Under FAR Part||Part 121|
|Navigation In Use||other vortac|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : multi engine|
pilot : commercial
pilot : instrument
pilot : atp
|Experience||flight time last 90 days : 200|
flight time total : 3700
flight time type : 1600
|Affiliation||government : faa|
|Function||controller : radar|
|Anomaly||other spatial deviation|
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : returned to intended or assigned course|
|Consequence||faa : reviewed incident with flight crew|
|Problem Areas||Navigational Facility|
|Primary Problem||Navigational Facility|
The fmn VOR (115.30) seems to oscillate by at least +/-1 DOT on VOR receiver obs continuously. This happens continuously at all distances and altitudes where fmn VOR can be received and positively identified. This happens on all airplanes that receive fmn VOR. Denver center was not aware that it was happening. ZAB center has had to tell us to get back on assigned airway on several occasions because VOR receiver needle will not track a straight and accurate course. Other vors don't do this--just fmn (115.30).
Original NASA ASRS Text
Title: PLT OF B190 RPTS THAT FMN VOR AZIMUTH GUIDANCE FLUCTUATES CONSTANTLY AT ALL ALTS AND DME RANGES. VARIATION IS A CONTINUOUSLY ALTERNATING PLUS AND MINUS ONE DOT.
Narrative: THE FMN VOR (115.30) SEEMS TO OSCILLATE BY AT LEAST +/-1 DOT ON VOR RECEIVER OBS CONTINUOUSLY. THIS HAPPENS CONTINUOUSLY AT ALL DISTANCES AND ALTS WHERE FMN VOR CAN BE RECEIVED AND POSITIVELY IDENTIFIED. THIS HAPPENS ON ALL AIRPLANES THAT RECEIVE FMN VOR. DENVER CENTER WAS NOT AWARE THAT IT WAS HAPPENING. ZAB CENTER HAS HAD TO TELL US TO GET BACK ON ASSIGNED AIRWAY ON SEVERAL OCCASIONS BECAUSE VOR RECEIVER NEEDLE WILL NOT TRACK A STRAIGHT AND ACCURATE COURSE. OTHER VORS DON'T DO THIS--JUST FMN (115.30).
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.