Narrative:

While conducting the ILS runway 35R approach to apa airport. From approximately the casse outer marker inbound to approximately 4 miles (DME) to end of runway. The glideslope indicators fluctuate (or porpoise) +/- 2 to 3 degrees from center. Two separate navigation receivers on the aircraft both showed the fluctuations. This is a recurring problem for this ILS approach to apa. Has been reported to tower at apa and confirmed by other aircraft on this same approach and at other dates.

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Original NASA ASRS Text

Title: LR45 ON ILS RWY 35R TO APA ENCOUNTERED GLIDESLOPE FLUCTUATIONS. RPTR STATES THAT THIS ANOMALY IS A RECURRING PROBLEM ON THIS APCH.

Narrative: WHILE CONDUCTING THE ILS RWY 35R APCH TO APA ARPT. FROM APPROX THE CASSE OUTER MARKER INBOUND TO APPROX 4 MILES (DME) TO END OF RWY. THE GLIDESLOPE INDICATORS FLUCTUATE (OR PORPOISE) +/- 2 TO 3 DEGS FROM CENTER. TWO SEPARATE NAV RECEIVERS ON THE ACFT BOTH SHOWED THE FLUCTUATIONS. THIS IS A RECURRING PROB FOR THIS ILS APCH TO APA. HAS BEEN REPORTED TO TOWER AT APA AND CONFIRMED BY OTHER ACFT ON THIS SAME APCH AND AT OTHER DATES.

Data retrieved from NASA's ASRS site as of January 2009 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.