Beechcraft C99 captain reported the HSI glide slope indicator malfunctioned.

Attributes
ACN	1506560
Time
Date	201712
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	Airliner 99
Operating Under FAR Part	Part 135
Flight Phase	Initial Approach
Flight Plan	IFR
Component
Aircraft Component	Compass (HSI/ETC)
Person 1
Function	Captain Pilot Flying
Events
Anomaly	Aircraft Equipment Problem Less Severe Inflight Event / Encounter Weather / Turbulence

Narrative:

While executing the ILS approach I noticed that the glideslope on my HSI was not responding or 'coming alive' like it should be for that segment of the approach. I tapped on the instrument and realized that it was stuck as the glideslope would move and stick in a new position. At this time I advised ATC that I was going missed and began executing the missed approach. My intention was to shoot the approach again using my navigation 2 but by that time the visibility had dropped below minimums so I diverted.

Original NASA ASRS Text

Title: Beechcraft C99 Captain reported the HSI glide slope indicator malfunctioned.

Narrative: While executing the ILS approach I noticed that the glideslope on my HSI was not responding or 'coming alive' like it should be for that segment of the approach. I tapped on the instrument and realized that it was stuck as the glideslope would move and stick in a new position. At this time I advised ATC that I was going missed and began executing the missed approach. My intention was to shoot the approach again using my NAV 2 but by that time the visibility had dropped below minimums so I diverted.

Data retrieved from NASA's ASRS site 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.