Narrative:

For several yrs, I've noticed that the kokomo VOR is very unreliable outside of about 30 NM if you're at high altitudes. More often than not, ATC will put you on a heading for okk if you don't have some kind of self contained navigation equipment (IRS, INS, omega). This VOR makes up part of the kokomo arrival to ord and, in my opinion, should be of substantially higher quality. Usual problems include constant 'scalloping' of the CDI needle when trying to track to the VOR from the south or even having the 'off' flag appear when within 50 NM of okk. Callback conversation with reporter revealed the following information: the reporter stated he was flying a B727-200. He said he had just recently returned to the 'steam gauges' from the 'glass.' the 'glass' instrumented airplanes do not have a problem. He stated the kokomo arrival is for the arrs from the south. He believes the problem is a similar frequency VOR down south interfering at high altitudes. He stated center is probably well versed on the problem, as frequently when the MOA is cold center will bypass kokomo and clear the flts direct to knox.

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Original NASA ASRS Text

Title: THE KOKOMO VOR HAS BEEN UNRELIABLE FROM THE S AT HIGH ALTS OUTSIDE ABOUT 30 MI FOR SEVERAL YRS. ATC WORKS AROUND THE PROB BY PROVIDING VECTORS. PROBs INCLUDE 'SCALLOPING' AND SOMETIMES AN 'OFF' FLAG UNTIL WITHIN 50 MI.

Narrative: FOR SEVERAL YRS, I'VE NOTICED THAT THE KOKOMO VOR IS VERY UNRELIABLE OUTSIDE OF ABOUT 30 NM IF YOU'RE AT HIGH ALTS. MORE OFTEN THAN NOT, ATC WILL PUT YOU ON A HDG FOR OKK IF YOU DON'T HAVE SOME KIND OF SELF CONTAINED NAV EQUIP (IRS, INS, OMEGA). THIS VOR MAKES UP PART OF THE KOKOMO ARR TO ORD AND, IN MY OPINION, SHOULD BE OF SUBSTANTIALLY HIGHER QUALITY. USUAL PROBS INCLUDE CONSTANT 'SCALLOPING' OF THE CDI NEEDLE WHEN TRYING TO TRACK TO THE VOR FROM THE S OR EVEN HAVING THE 'OFF' FLAG APPEAR WHEN WITHIN 50 NM OF OKK. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED HE WAS FLYING A B727-200. HE SAID HE HAD JUST RECENTLY RETURNED TO THE 'STEAM GAUGES' FROM THE 'GLASS.' THE 'GLASS' INSTRUMENTED AIRPLANES DO NOT HAVE A PROB. HE STATED THE KOKOMO ARR IS FOR THE ARRS FROM THE S. HE BELIEVES THE PROB IS A SIMILAR FREQ VOR DOWN S INTERFERING AT HIGH ALTS. HE STATED CTR IS PROBABLY WELL VERSED ON THE PROB, AS FREQUENTLY WHEN THE MOA IS COLD CTR WILL BYPASS KOKOMO AND CLR THE FLTS DIRECT TO KNOX.

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.