Confusion with my KFC-150, G5 HSI, GI-275 and a 530W

[jaylw314]

2 hours ago, skyfarer said:

The AFMS for the KFC-150, the 530W, and the KAS-297B are in the POH. The GI-275 and G5 supplements are easily found online and I have those, BUT... what I really need is to get from Crystal Avionics, the AFMS they should have provided that contain specifics to my airframe installation.

I'm close to finishing my instrument rating, so I only fly this plane VFR at present. But, soon I'll be rated and want all this documentation in order so that I understand all the limitations and operation of the setup.

On the one hand, the AFMS for those should all apply to your plane, since the equipment in question has to be installed according to the requirements of the installation instructions and the STC.  For that matter, I think it's technically not possible for an avionics installer to replace the KAS-297B without knowing that it works or is connected, since if it fails functional testing it would have to be placarded as INOP.

On the other hand, installers are human too and have been known to make mistakes.

If you're not doing your IFR training in this plane, I'd say you'll definitely want to go over the manuals with a fine-toothed comb, check out the free Garmin 530W simulator app, and have a good chunk of time with an instructor to transition.  There are all sorts of 'gotchas' with the interface between the KFC 150, KAS 297B and G530W.  For example, on the outbound course of the ILS, do where do you point the arrow on the HSI?  How do you fly holds?  What happens with a HILPT?  The answer for those and many questions is "it depends".  You don't want to run into a question you don't know the answer to when you're in the soup.

2 hours ago, jlunseth said:

Probably more than you want to know but here goes. The 150 and 200 are analog AP's.

Technically, the KFC-150 is a digital autopilot.  I'm not sure about the 200, but it may be analog.  Not that there's a practical difference on the pilot's side so I'm just being pedantic  

[PT20J]

36 minutes ago, jaylw314 said:

Technically, the KFC-150 is a digital autopilot.  I'm not sure about the 200, but it may be analog.  Not that there's a practical difference on the pilot's side so I'm just being pedantic  

You're right. The KFC 200 is analog. Big old box of circuit cards in the back of the airplane. The panel mount KAP/KFC 150s are digital with a microprocessor. Those three are attitude based. The KAP 140 is digital but rate based. The GFC 500 is digital, of course, and I believe primarily attitude based with some rate based computations.

[Fly Boomer]

50 minutes ago, PT20J said:

Attitude is fed to the autopilot from the KI 256 and the autopilot drives the KI 256 flight director command bars. There is no connection between the KI 256 and the other avionics.

What drives the flight director command bars when the autopilot is off?

[N231BN]

1 hour ago, skyfarer said:

Thanks, this is interesting. Can you also provide the STC No. you have here? I see in the logs where the G5's were installed and the KI256 moved, I'll review these STC's. Then about 13 months later, the GI-275 ADAHRS/AP was installed, replacing the KI256. I also have an A&P/IA that I trust looking over all this, plus another avionics guy who is the go to autopilot guy around here. Hopefully we'll get this figured out and make sure I'm airworthy and safe for flight into IMC.

The G5 installation manual can be downloaded from the Garmin website: https://support.garmin.com/en-US/?partNumber=K10-00280-01&tab=manuals

You do see a few airplanes configured this way with the GI-275 providing attitude and the G5 sending heading and course info but the install diagrams for the GI-275 don't show that, it's all or nothing. The GI-275 is such an amazing instrument for what it is, when a legacy autopilot is involved it's in an entirely different class than a G5.

It is possible they requested and received a field approval for the installation of both a G5 and GI-275 connected to the autopilot.

[skyfarer]

1 hour ago, Fly Boomer said:

What drives the flight director command bars when the autopilot is off?

The flight director command bars are not present until I hit the FD button on the KFC-150. So to answer your question, I would say nothing drives them when the autopilot is off so they disappear.

[PT20J]

26 minutes ago, skyfarer said:

The flight director command bars are not present until I hit the FD button on the KFC-150. So to answer your question, I would say nothing drives them when the autopilot is off so they disappear.

Exactly. The command bars are simply a visual display of what the autopilot is doing. The only difference between FD and AP modes is engagement of the servos.

[Bolter]

19 hours ago, hais said:

I think that’s how it is supposed to work. @skyfarer, what happens when you set the CDI on the 530 to VLOC, the KFC150 to HDG, and G5 to GPSS?

I think that my original post was incomplete/unclear.  GPSS on the G5 with the HDG mode on the AP was ONLY for GPS navigation.  VOR tracking was always NAV on the AP (VLOC on the 430W), which is to say no GPSS for VOR tracking.

[Pinecone]

10 hours ago, jaylw314 said:

The workflow with the KAS-297B is to set your desired altitude, then set your desired vertical speed, then arm VS and ALT.  It will not do anything until you press VS.  If you are in HDG or NAV mode but manually pitched for a climb/descent, pressing ALT will capture your desired altitude when you hit it without changing your current climb/descent.

I have a KAP-150 with KAS-297B.

I does NOT capture altitude if you are manually pitched.  It must have VS activated.

[jlunseth]

Thanks for the clarification that the 150 is digital Skip, as I said, I don’t have one so no experience. However, I looked at the manual for the KFC150 and it appears to me that the operation from the pilot’s perspective is just the same as the 200, for example, on an ILS approach. The old way, before GPS, was that the bug would be used to fly the procedure turn and somewhere before final approach course intercept the pilot would put the AP in APCH mode. That would “ARM” the APCH mode, and the AP would use the closure rate to determine capture of the localizer. After localizer capture and flying inbound, APCH would switch to CPLD in my plane, and in the KFC 150 the manual says the light on the annunciation goes from blinking to solid and the ARM annunciation disappears. The aircraft then flies into the glideslope and couples to the slope. 

There is a Backcourse mode for both the 150 and the 200, so if you are flying the outbound backcourse you can put the AP in APCH and Backcourse and it will let you fly the procedure turn using the heading bug and it is apparently automatically set to ARM and capture the LOC. I don’t use Backcourse with my 200, it does not seem to play well with a GPS (my AP has been run with a 430 and currently with a 750 Xi). I just use HDG on the AP and GPS mode on my GPSS (an Icarus SAM) which will fly the entire backcourse including the procedure turns. 

However, the important point is that shortly before Localizer intercept the AP must be put into APCH, it will then ARM and it will couple to the Localizer and then couple to the GS when the aircraft gets there. Also, the GPS must be in VLOC with the correct ILS frequency in the top slot, or there will be no LOC or GS signal for the AP to use. 

A nifty thing in the 750, although off the point, is that the step of IDng the ILS is done automatically. The 750 decodes the Morse code and if correct, will put the KLVN ILS in small print above the ILS frequency in the active Nav frequency window.

I noticed a note in the 150 manual that GS is locked out for RNAV and VOR approaches, when the 150 is in APCH mode. Not sure how this works with modern LPV approaches or the relatively new RNAV approaches for VORs that compute a GS. I am guessing Garmin and others have figured out a way to fool the AP into believing it is flying an ILS and it uses the calculated slope from the GPS.

[jaylw314]

13 hours ago, Pinecone said:

I have a KAP-150 with KAS-297B.

I does NOT capture altitude if you are manually pitched.  It must have VS activated.

Even if ALT is armed?  That is interesting, that must mean there are different ways to install it

[jaylw314]

17 minutes ago, jlunseth said:

A nifty thing in the 750, although off the point, is that the step of IDng the ILS is done automatically. The 750 decodes the Morse code and if correct, will put the KLVN ILS in small print above the ILS frequency in the active Nav frequency window.

I noticed a note in the 150 manual that GS is locked out for RNAV and VOR approaches, when the 150 is in APCH mode. Not sure how this works with modern LPV approaches or the relatively new RNAV approaches for VORs that compute a GS. I am guessing Garmin and others have figured out a way to fool the AP into believing it is flying an ILS and it uses the calculated slope from the GPS.

The KFC-150 can certainly fly an RNAV LPV approach in approach mode.

What you'll find not cool about the GNS530W is that there is no means to display distance to the ILS.  VOR yes, it will display ground distance in the little window under the frequencies, but for an ILS, it will not.  You'll need to add up the leg distances or keep a DME on the appropriate frequency

[Pinecone]

3 hours ago, jaylw314 said:

Even if ALT is armed?  That is interesting, that must mean there are different ways to install it

Yeap.

I thought it was not working at all to capture, but it would hold.  Then I was using VS and it captured fine.

[jlunseth]

8 hours ago, jaylw314 said:

 

What you'll find not cool about the GNS530W is that there is no means to display distance to the ILS.  VOR yes, it will display ground distance in the little window under the frequencies, but for an ILS, it will not.  You'll need to add up the leg distances or keep a DME on the appropriate frequency

When I put the 750 in I pulled an old KNS80, good unit but took up alot of room. I put a slim little DME in just so I can get VOR and ILS distances, although I can't think of much reason to get an ILS distance. Mostly I use it to fly traditional VOR approaches just for practice. 

[PT20J]

10 hours ago, jlunseth said:

Thanks for the clarification that the 150 is digital Skip, as I said, I don’t have one so no experience. However, I looked at the manual for the KFC150 and it appears to me that the operation from the pilot’s perspective is just the same as the 200, for example, on an ILS approach. The old way, before GPS, was that the bug would be used to fly the procedure turn and somewhere before final approach course intercept the pilot would put the AP in APCH mode. That would “ARM” the APCH mode, and the AP would use the closure rate to determine capture of the localizer. After localizer capture and flying inbound, APCH would switch to CPLD in my plane, and in the KFC 150 the manual says the light on the annunciation goes from blinking to solid and the ARM annunciation disappears. The aircraft then flies into the glideslope and couples to the slope. 

There is a Backcourse mode for both the 150 and the 200, so if you are flying the outbound backcourse you can put the AP in APCH and Backcourse and it will let you fly the procedure turn using the heading bug and it is apparently automatically set to ARM and capture the LOC. I don’t use Backcourse with my 200, it does not seem to play well with a GPS (my AP has been run with a 430 and currently with a 750 Xi). I just use HDG on the AP and GPS mode on my GPSS (an Icarus SAM) which will fly the entire backcourse including the procedure turns. 

However, the important point is that shortly before Localizer intercept the AP must be put into APCH, it will then ARM and it will couple to the Localizer and then couple to the GS when the aircraft gets there. Also, the GPS must be in VLOC with the correct ILS frequency in the top slot, or there will be no LOC or GS signal for the AP to use. 

A nifty thing in the 750, although off the point, is that the step of IDng the ILS is done automatically. The 750 decodes the Morse code and if correct, will put the KLVN ILS in small print above the ILS frequency in the active Nav frequency window.

I noticed a note in the 150 manual that GS is locked out for RNAV and VOR approaches, when the 150 is in APCH mode. Not sure how this works with modern LPV approaches or the relatively new RNAV approaches for VORs that compute a GS. I am guessing Garmin and others have figured out a way to fool the AP into believing it is flying an ILS and it uses the calculated slope from the GPS.

I believe that BK tried to design the KFC 150 to work like the KFC 200 so pilots would not have to learn a new system. I had the KFC 200 in my 1978 M20J and had the KAP 150 in the 1994 M20J and the logic is the same. The KFC 150 is a really good autopilot. It doesn't have some of the vertical modes of the newer GFC 500, but it flies GPS approaches well especially if you have a Garmin or Aspen that provides GPSS capability and with a WAAS navigator, it will fly LPV with GS.

To understand how it can do LPV requires backtracking to the original design. APR mode arms the GS. But for the GS to go active requires that the navigator send an ILS Energize signal to the autopilot. This normally occurs when a conventional Nav/Com is tuned to an ILS frequency. When a GNS 430W (or any WAAS navigator) is used, the ILS Energize signal is sent when either an ILS is tuned in VLOC mode, or a GPS approach with vertical guidance is active in GPS mode.

Skip

 

[jaylw314]

2 hours ago, jlunseth said:

When I put the 750 in I pulled an old KNS80, good unit but took up alot of room. I put a slim little DME in just so I can get VOR and ILS distances, although I can't think of much reason to get an ILS distance. Mostly I use it to fly traditional VOR approaches just for practice. 

There are some ILS approaches with waypoints marked by DME distance and no VOR on the field.  Thinking of you, KSLE.  Normally, if you tune in a VOR for an approach without programming it, you expect to get the ground distance to the VOR in that little window in the GNS530W that you can use in lieu of DME distance.  But when you go to tune in ILS without setting it up, doh!  Suddenly you realize you have no easy way of figuring where on the localizer you are and if you've passed a fix yet.

Obviously there are workarounds, like programming the approach each and every time so you can see the fixes, but it's one of those things that seems like it should work and can catch you out when you realize it doesn't.

I don't know if the 750 has the same quirk.  It seems like it'd be trivial for Garmin to calculate the ground distance just like with a VOR.

Edited January 30, 2023 by jaylw314

[Pinecone]

Hmm, I have to check, but I thought my 650 showed time and distance to each fix on the approach.

[jlunseth]

Yeah, I have a 430 as a backup to the 750 and it works that way also. Not sure about the 750 myself. Don’t think we have one of those “distance to ILS” approaches around here, not that I have run into.

To the OP, I hope we cleared up some of the confusion about what is doing what on your panel. Skip’s comments were great. 

Probably a little too deep a dive, but the King AP’s are generally attitude based APs, meaning they use attitude information from the AI. In your panel, the source of that is the 275. So although it might be a little weird, your 275 is the primary instrument feeding rate information to the AP and the lower G5 is the source of horizontal guidance information. It may be that the upper G5 is hooked to the system to reflect what is showing on the 275, but the 275 is the source for the AP. 

In my installation, auto switch in the GPS is not yet working correctly. I have to manually make the switch to VLOC in the 750 (like your 530) and that works fine for an ILS. The whole system is now using the LOC/ILS signals for horizontal and vertical (GS) guidance. In my installation that is not working right for VORs. To use the VOR signal, I have to both (1) put the GPS in VLOC and (2) use the CDI button in the 275 to manually change over to VOR mode. I am going to have my avionics shop look at it. I am just telling you so you know that when the 530 is put into VLOC you should see the course needle on the 275 change from magenta to green, and if it doesn’t you have to go into CDI on the 275 and manually switch the 275 into VOR mode. It will annunciate VOR and there is the color change to tell you what is happening. If the thing is still in magenta the 275, which is driving your AP during an approach, it is not using the VOR signal to drive the AP. Don’t know why this quirk exists, it may just be my install, but it does happen.

Edited January 30, 2023 by jlunseth

[rbp]

14 hours ago, jaylw314 said:

Suddenly you realize you have no easy way of figuring where on the localizer you are and if you've passed a fix yet.

Obviously there are workarounds, like programming the approach each and every time so you can see the fixes, but it's one of those things that seems like it should work and can catch you out when you realize it doesn't.

 

wait -- when you're assigned an ILS approach, you don't load it into the 530? you just tune the ILS frequency?

loading the approach is how you get the "in lieu of DME" fixes and the missed approach. or do you fly the missed on the VOR?

[midlifeflyer]

11 minutes ago, rbp said:

wait -- when you're assigned an ILS approach, you don't load it into the 530? you just tune the ILS frequency?

loading the approach is how you get the "in lieu of DME" fixes and the missed approach. or do you fly the missed on the VOR?

Good point

[jaylw314]

4 hours ago, rbp said:

wait -- when you're assigned an ILS approach, you don't load it into the 530? you just tune the ILS frequency?

loading the approach is how you get the "in lieu of DME" fixes and the missed approach. or do you fly the missed on the VOR?

I like flying approaches with just the radios sometimes, what can I say?  

I wasn't too clear, sorry, I was specifically referring to an approach where the DME is associated with the ILS frequency.  Normally, if you did an ILS approach without programming it in the 530, you'd have a second radio tuned to a different navaid to figure out your fixes.  It's not patently obvious that even when you tune the 530 to the ILS-DME, you still need to tune your second radio or DME to the exact same frequency to get your distance for identifying fixes, especially since for a VOR-DME approach, you wouldn't because the 530 does show you the ground distance.  Like I said, it's not a showstopper, but it's an inconsistency that can trip up someone not familiar with it.

A more annoying situation this can be a problem even if you've programmed the approach in the 530 is if you've gotten vectors-to-final on an ILS-DME and pressed that button, then suddenly ATC asks you if you're past a certain fix.   "uhhh....narp?"  Again, not a big deal if your nav radio is on the same frequency

Edited January 31, 2023 by jaylw314

[jaylw314]

On 1/28/2023 at 7:25 PM, Pinecone said:

I have a KAP-150 with KAS-297B.

I does NOT capture altitude if you are manually pitched.  It must have VS activated.

Oooh, I completely missed that you had a KAP-150, sorry!

[PT20J]

4 hours ago, rbp said:

wait -- when you're assigned an ILS approach, you don't load it into the 530? you just tune the ILS frequency?

loading the approach is how you get the "in lieu of DME" fixes and the missed approach. or do you fly the missed on the VOR?

EXACTLY. When you load the approach and make it active, the navigator provides VLOC course guidance to the CDI, but the GPS drives the map and still sequences legs and reports distances to waypoints.

[rbp]

2 hours ago, jaylw314 said:

It's not patently obvious that even when you tune the 530 to the ILS-DME, you still need to tune your second radio or DME to the exact same frequency to get your distance for identifying fixes

selecting a VOR, LOC, or ILS frequency will automagically tune the DME radio to the paired frequency. In every plane I've flown that doesn't have a selectable DME (eg KDI-572), the DME is paired to NAV1

are you saying that your DME is paired to NAV2, and not to the 530 NAV1, so you have to tune both radios to the same VLOC to get the colocated DME?

[rbp]

2 hours ago, jaylw314 said:

A more annoying situation this can be a problem even if you've programmed the approach in the 530 is if you've gotten vectors-to-final on an ILS-DME and pressed that button

there's a long thread about this: 

 

[jaylw314]

1 hour ago, rbp said:

selecting a VOR, LOC, or ILS frequency will automagically tune the DME radio to the paired frequency. In every plane I've flown that doesn't have a selectable DME (eg KDI-572), the DME is paired to NAV1

are you saying that your DME is paired to NAV2, and not to the 530 NAV1, so you have to tune both radios to the same VLOC to get the colocated DME?

Yes, my DME is not paired to the 530 in terms of frequency tuning.  I know it can, and I'll probably do that next time I'm in the avionics shop, but I'm trying to avoid them as long as I can