1ang Posted November 28, 2019 Report Share Posted November 28, 2019 Got a question, see if anyone else had this issue and what the fix was. Trying to see if I can avoid brining it to the shop: Have a 525 HSI and the heading bug won’t move, the dial spins freely but does not move the bug. Made my trip back home from thanksgiving a little more difficult then I wished. Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted November 28, 2019 Report Share Posted November 28, 2019 Is the shaft moving or just the knob? Is there a set screw? (I am commenting w/o knowing anything about design the particular device.) Quote Link to comment Share on other sites More sharing options...
1ang Posted November 28, 2019 Author Report Share Posted November 28, 2019 Is the shaft moving or just the knob? Is there a set screw? (I am commenting w/o knowing anything about design the particular device.) The know and the visible shaft behind the face is moving but then I can’t see anymore past that because of the secondary face behind the glass. The shaft does have a flat face too it. Just trying to see if anyone knows of this shaft become disconnected or if I have to take it to a shop Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 28, 2019 Report Share Posted November 28, 2019 ang, Sounds like the indicator has become mechanically disconnected from the rest of the device... ? Does the AP still work otherwise? Like does the plane go in the direction, it thinks the indicator is showing, and head towards a new heading when the knob is turned? essentially I’m asking if the indicator came loose, vs. the knob coming loose... if the knob is falling off the shaft... that is something you can easily fix... if the indicator has come loose inside the HSI... a local instrument shop may be able to fix it... if the problem is internal and can’t be fixed locally... used BK HSIs are streaming into the market lately... PP thoughts only, not an instrument guy... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted November 28, 2019 Report Share Posted November 28, 2019 4 minutes ago, 1ang said: The know and the visible shaft behind the face is moving but then I can’t see anymore past that because of the secondary face behind the glass. The shaft does have a flat face too it. Just trying to see if anyone knows of this shaft become disconnected or if I have to take it to a shop Don't know if this would help. The cover pic does show a set screw but I guess you've progressed beyond the obvious.... https://www.bendixking.com/en/~/media/bendixking/files/006-08256-0004_4-kcs-55-55a-ki-525a-pilot-s-guide.pdf 1 Quote Link to comment Share on other sites More sharing options...
1ang Posted November 28, 2019 Author Report Share Posted November 28, 2019 ang, Sounds like the indicator has become mechanically disconnected from the rest of the device... ? Does the AP still work otherwise? Like does the plane go in the direction, it thinks the indicator is showing, and head towards a new heading when the knob is turned? essentially I’m asking if the indicator came loose, vs. the knob coming loose... if the knob is falling off the shaft... that is something you can easily fix... if the indicator has come loose inside the HSI... a local instrument shop may be able to fix it... if the problem is internal and can’t be fixed locally... used BK HSIs are streaming into the market lately... PP thoughts only, not an instrument guy... Best regards, -a- AP Still flyovers the heading bug, thankfully for a portion of my flight the bug was on the actual needed heading, lucky lucky. The know is the issue it spins with no resistance Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 28, 2019 Report Share Posted November 28, 2019 Ang, that’s a good sign... for low cost... next, check the knob is connected to the shaft... (see Bob’s pic of the set screw in the knob...) Best regards, -a- Quote Link to comment Share on other sites More sharing options...
PT20J Posted November 29, 2019 Report Share Posted November 29, 2019 The KI 525A is purely a simple electro-mechanical device since the gyro is remote. You can open the case and see pretty quickly what's going on. 1 Quote Link to comment Share on other sites More sharing options...
Jerry 5TJ Posted November 29, 2019 Report Share Posted November 29, 2019 The KI-525A has become inexpensive as many reach the market now as we upgrade. A purchase of a used unit may be cheaper than an overhaul. 2 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.