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Spitzer
10-20-2020, 03:32 PM
Hi everyone!

Maybe I can get some help here.

On my Lancair 360 I have a Bendix King KCS 55A HSI and I'm having some problems whith it. Yes, I know... Who this days still use this old technology so prone to fail? Right now I cannot spend too much money on the panel, and I don't fly IFR, so I'm trying to solve this with no rush.

As you can see on the video I post here, the HDG flag is out and the compass card is dead. And if I rotate the HDG bug, all the card rotates with it. If I try to unslave and rotate freely, also nothing happens.

On the KG 102A remote unit, I can hear the gyro spinning. I know this unit needs an overhaul after several years, but normaly, for what I read, the symptons for a repair are errors on the compass card or lag reaching the heading. On this case, the "gyro" / heading doesn't work at all.


Do you have thoughts on this?

Thank you all in advance

David

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https://youtu.be/uaSDvWZSz0c

Kurt Flunkn
10-21-2020, 12:32 PM
Send it to aircraft quality instrument repair. I've used this instrument shop several times over the years with fast turn around at fair prices.

http://flyaqi.com/home.htm

Spitzer
10-21-2020, 03:12 PM
Hi Kurt,

Thanks for your answer ;). Will get in touch with them.

David

Mayhemxpc
10-22-2020, 06:25 AM
And don't apologize about using steam gauges! Like most things, they wear and need servicing from time to time.

laytonl
10-22-2020, 06:43 PM
Bob Bramble at Aerolab aviation is another good resource. Reasonable and his work is excellent. Lee

https://www.aerolabaviation.com/AEROLAB%20AVIATION%20CONTACT%20US.html (https://www.aerolabaviation.com/AEROLAB%20AVIATION%20CONTACT%20US.html)

FlyingRon
10-25-2020, 11:06 AM
I may have missed it, but have you tried putting it in free gyro mode (i.e., turn off the slaving). My KCS-55 periodically goes wonky and fails to bootup the magnetic heading. The heading flag stays flagged and the like.

2ndsegment
10-25-2020, 12:07 PM
This thread exactly shows me where to perk up. When worked in Pratt & Whitney Field Service in 1980 there were things that mechanics at the various levels worked on as Field, Organizational and Depot and other things that went to PMEL (Precision, Measurement and Equipment Laboratory.) There were other things that showed how Digital was coming to take over some functions. An example was the EEC (Engine Electronic Control). Meanwhile out at the Test Area a cobbled up thing was being removed from a test stand and left in the open air as the engine was taken elsewhere. It was the FADEC (Full Authority Digital Engine Control.)

Now then, did I know what a HSI (Horizontal Situation Indicator) was? Sure, but for me it was a page on a CRT or later flat panel in what came to be called The Glass Cockpit. These kind of Rubik's cube puzzles of gauges that displayed decades of data as 360 rotations of various size pointers and .. any way it all came to a head the day of the first Space Shuttle Mission into space. At two minutes to go in the count down, the clock was stopped because the Flight Control Instrument (which worked on a round earth with an atmosphere) could not synchronize with the Mission Control Instrument (which worked in a physical universe where all matter had gravitational attraction and where bodies rotated and precessed.) Back to your problem and where King Radio is now.

I watched the Space Shuttle fly the next day from the Otis Escalator porch of the former RCA computer plant. So much for modal flags and so much for heat absorbent tiles.

FlyingRon
10-25-2020, 01:39 PM
Even though digital displays and solid state sensors have greatly increased the reliability and simplified somewhat the HSI, the various functions still exist and in some cases as separate units. The G5 in HSI mode needs a backup battery, the GMU 11 magnetometer, and additional stuff to interface to the GPS (over and above the simpler resolver interfaxe used by the KCS55).

ACE01
11-20-2020, 06:37 AM
The cost to repair and overhaul this unit in my opinion is not worth the effort. Invest in a Garmin GI275 with ADHARS. You will be much happier in the long run. https://www.kitplanes.com/product-review-garmin-gi-275-efis/