Mike: If I could bother you once again. I was offered a King KG 258 attitude indicator for a good price. I bought it and the tag on the side says that it is to be placed in a 8 degree panel only. Can I use this in my Musketeer or should I sell/trade for one that will work. Right now my panel has the old AN style and I was hoping to upgrade to a better unit for my instrument training.
Thanks, Ashley
Ashley, I’m not very knowledgeable about avionics. Here is about all I know (or can find out) about the KG-258:
It is a relatively high-end, autopilot-sensing artificial horizon.
It was most commonly sold in conjunction with a King 100, 150, or 200 autopilot. The purchaser of a King autopilot had to select either an Attitude Indicator or a Flight Director; the KG-258 was the AI selection.
The pricing on these seems to be around $1,800 overhauled outright, $1,100 overhauled exchange, and $6,000 new. Used and untagged ones will bring whatever someone is willing to pay for an undocumented unit.
I don’t know whether it is true of any other Horizons (I’ve never seen it mentioned in another brand), but the King units apparently came in a 0-degree tilt, a 5-degree tilt, and a 8-degree tilt.
Frankly, I had assumed that “tilt” had to do with how vertical the panel sits in cruise flight; but for all I know it could refer to an angled panel (though I doubt it). If a gyro is not perfectly level, it reacts differently to a change in position (differently than intended). In fact, that’s what makes the difference between a Turn And Bank and a Turn Coordinator. The gyro is mounted at an angle in the TC, so that it reflects yaw rather than only bank.
Sounds to me like you need to take a protractor up flying with you, and see if you have any panel inclination in normal cruise flight. Then talk to a good instrument shop about it. Another possibility might be to locate another 19/23/24 driver who has a King 100/150/200 Autopilot, and find out what the Tilt is in their Horizon or Flight Director. That would be a clue about what will work for you. Unfortunately, I have never seen nor heard of a King AP in these models. Someone may have added one over the years, though.
Sorry that I just don’t know much on this subject. See if anyone else can help out.