GPS 175 and ???

[Mellow_Mooney]

Hey Everyone,

Wondering what minimum equipment I need to upgrade my panel to be able to fly gps approaches. I am not worried about easy vs hard, just want the ability to do so at the cheapest entry cost. One avionics installer is saying I need to install an HSI and one is saying I don’t. I’m curious what you all think and if you have any insight on my panel. 
 

If possible, I would install the gps 175 and use it with a switch for my CDI or install a second instrument, but would prefer to keep it something low cost. My avionics guy is suggesting a g5 or gi275 but I’d rather not shell out the money for that if I don’t have to. Or - can I just use my existing equipment with the gps 175?
 

any ideas to keep my entry costs low and still able to fly RNAV and all other approaches?

 

still training ground for instrument rating but want to get this upgraded for training. Please bare with me if my terminology is incorrect…

 

My home airport only has gps approaches that bring you below 1000’ so that is the biggest reason I want the gps approach systems. 
 

Thanks for your help in advance.

 

-Mellow

 

 

[hammdo]

G5 and GNC 355 (COM)/375 (Transponder/ADSB) are good options.

i have dual G5s and GNC355, kept the BK 155 and indicator…

 

 

[PeteMc]

Sure, you can use what you have.  But I'd seriously consider the GI275 if you do upgrade. 

And rather than the GPS175, might I suggest you look at the GNC355.  You'd then be swapping out one of  your Nav/Comms with a GPS Nav/Comm  And you'd have the second original Nav/Comm for VOR/ILS/LOC as needed.

[McMooney]

looking at your panel you look pretty good,  a 175 and a new G5/ GI-275 sill set you up nicely.  I believe the CDI you have would be compatible btw.

as you have 2x nav/comms already you could even go a gnx375 for adsb-in(i'd probably do this )

keep the dme, mine saved me on my checkride.  DPE failed my gps, asked what i would do now, expecting me to start timing.  instead, i just pointed at the DME, landed the plane and walked away IR rated.

 

 

 

Edited April 23, 2024 by McMooney

[Pinecone]

You can do a GPS install with an old school CDI.  One CAP C-182 I fly has this setup.  There is a switch to change the CDI input from the nav/com to GPS.

BUT, an HSI is such a much better instrument you will be happy if you put one in.

[LANCECASPER]

You have a King KLN89 GPS installed. If you want to go cheap-cheap, since a lot of these are on the market you could slide in a KLN89B or KLN94, which are both "approach certified", but not WAAS. You would probably need new coaxial, new antenna, paperwork, etc. That being said, here's why I wouldn't do that. Every penny you spend on that you will never get back and it won't accomplish what you want for your end goal - WAAS approaches

Even if you can't do it immediately and you need to save up for it, do the WAAS GPS and HSI together on the same install. 

The 175 will do what you want, but here's why I would consider getting a 375 with the transponder built in.  1) Your King KT76 transponder has a cavity tube which will go out eventually and unplanned - then you're faced with doing it. 2) you will have ads-b in/out on the same device and be able to see traffic & weather on your route plus it will bluetooth that info out to your tablet 3) no matter what you do with your panel later, the 375 will stay and will have freed up some space.

With your round instruments already and the increased capability I would get the GI275 indicator. It will be much less expensive to do it together than separately and with the SVT option will make your instrument training much easier. Also when you do it together the installer has to make sure everything he touches works together. Doing it twice, when something doesn't work, will get blamed on the previous install - even if it was done by another person at the same shop. 

Edit - the more I look at your panel - if you're planning on keeping this airplane any length of time I would cut a new left panel and get your instruments in a configuration where you can do a meaningful scan. Learning on this panel will be unnecessarily difficult to get your IFR rating and even if you get through it you will have to unlearn your scan if you fly anything else. @Aerodon cuts panels.

[Utah20Gflyer]

I have a KLN 89b that is IFR but needs the internal battery replaced which my avionics guy said he’d do for $250.   The screen is excellent and I used it for navigating around before I replaced it with a Garmin 355 gps /com.  If your gps is already hooked up to a CDI that would be a cheap way to go to get RNAV.   Database updates are much more complicated than the newer stuff though.   I’d sell it to you real cheap.  
 

If I was going the new route I would do a GI 275 HSI which is what I did.   There are a lot of benefits to an HSI over a CDI.  I wouldn’t want to go back.  I would also recommend the 355 over the 175 because it’s nice have a new digital radio with a frequency database.   The 375 is a nice option as well with the ADSB capability.  

[joepilotmooney]

Just wondering has anyone been looking at or have experience with the Uavionix AV30 instruments??

[Zippy_Bird]

Hi @Mellow_Mooney

I am in the same boat.  Have mostly the same avionics only difference being the VFR GPS.  A few things on my mind:

- IFR GPS aside the condition of all other required avionics.  The POH specifies instrumentation required for IFR flight, and in my case the ancient 2" Turn and bank coordinator is dead so that is part of my upgrade conversation.  Hopefully everything you have is working great.

- An older CDI maybe compatible with newer IFR GPS signal sources, but may require a separate annunciator panel be installed for legal IFR flight.  The documentation of the make/model of the CDI should illuminate installation requirements.  If I go with a CDI, I'll likely purchase a used GI-106A or GI-106B and ditch my oldest VOR-only NAV head.  Those models have the annunciators built into the faceplate.

- If I piece-meal together a system I need to account for an IFR GPS Antennae to replace the current VFR one and also account for the wiring harnesses.  

- I have looked into installing used avionics (with 8130 forms) but the issue there is HOW to install them.  Finding experienced folks willing to install equipment they didn't sell is in short supply.  There is a robust market for used avionics, but not so much for installing them.  I am looking into it, but good money into old equipment is a question mark.  Is this the "forever plane" or a "good enough for now" plane?  I have not decided.  ;-) 

- My local shop gave me a quote this past winter to do Two(2) Garmin GI-275s and one GNX-375 (GPS NAV/ADSB-IN-OUT/Transponder) for $16.5K.  One reason I point this out is because the Garmin STC allows a pair of GI-275 to eliminate all other avionics requirements.  A six-pack can become a two-pack.  This differs from the Garmin G5, uAvionix AV-30-C, and the RC-Allen Mini 6.  All these require current avionics to remain in their original installed position.  This is not something you asked after, but this solution kills two birds for me. 

- AN analysis paralysis I am experiencing is due to Brittain auto-pilot integration.  I really really want to install a Brittain B-11 Accutrak to augment my basic wing leveler and I have collected all the parts.  Just about to send them out for rebuild.  Interfacing a modern GPS Nav with this old-school kit takes some thinking.  Old CDIs do it easily, but not sure a new GI-275 can.

- One last thing then I'll finish.  Have you considered doing your IFR training and check-ride in the plane as is?  Good or bad I have been thinking about this.  Both our planes are equipped to do an ILS, VOR, and DME approach.  Three approach types.  How did folks get their IR before GPS?  Maybe not my best idea, but its an idea.

Thank-you for starting this thread!   As I learn more I'll parachute in to add what I learn.

Sincerely,

Zippy_Bird

 

 

 

[vik]

If you want the cheapest option - here it is.

Pull out and sell KX-155 w/o GS and its CDI. Your CDI is not compatible with the GPS. And your new GPS will serve as a second VOR if needed.  There are probably few approaches left in the country that require two VORs. I did not see one for a long time.

Pull out and sell DME while you can. You won't need it with an IFR certified GPS as your new GPS can substitute for DME.  See https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_90-108_Chg_1.pdf

Buy KLN94 + CDI and harness from me I accidentally have one sitting on the shelf. You can also buy KLN89b. Those do not have a moving map. That should not be a show stopper since you want the cheapest , but they also require annunciators to be installed, which will add to the installation and will be a wash with no moving map.  

Put new CDI into the hole from your old one.

Slide in KLN94 and use your KLN89 as a door stop. It worth less than the shipping probably, but I might be wrong.

Unfortunately, there is one extra piece of work to do - you will have to connect KLN94 to your blind encoder. It is 9 wires, but without it your installation will not be IFR certified.

Keep your existing GPS antenna. KLN94 will work just fine with it.

Remove GPS limitation sticker after somebody signs off your logbook.

You will be able to fly all approaches except LPV.  I am not sure if any NDB approaches are still available, but if they are you are all set even if the beacon antenna was already knocked off. See the AC linked above.

You should break even after you sell your KX-155 and DME unless you have to pay somebody to crimp the above mentioned 9 wires. These days you might need a bank loan to pay for that labor.

Since you already have an audio panel installed, you might consider buying a second com and installing it into the free DME slot. Maybe you can get a Kx97. The tray should be very similar. Switch the wires from your old KX155 and you should be done. Or iCom A-200 will also work, but will require a different tray. We are talking more $$$ though. Handheld will do in case of the primary com failure. It all depends on your mission.

Sounds like a plan?

Vik

 

Edited April 24, 2024 by vik
Typo

[Zippy_Bird]

12 hours ago, joepilotmooney said:

Just wondering has anyone been looking at or have experience with the Uavionix AV30 instruments??

Yes.  I have looked at the AV-30-C very closely and my AP/IA installed one last year for a fellow Mooney driver.  The STC has some strict limitations that may make it less appealing for some, but for others it may be just right.  You can find the full STC doc on their website, but to paraphrase:

1. Absolutely no autopilot interfacing of any kind allowed
2. It cannot be installed as an HSI
3. If replacing a primary AI the airspeed and altimeter must remain where they are
4. A wet compass must be installed

Its my opinion that if one needs to replace an aging primary vacuum AI, and would like a non-vacuum replacement that is plug-in-play, it is perfect for that at $2,300.

But, it is NOT an IFR instrument.  Even if you don't want an HSI you cannot use it as a CDI for IFR approaches.  Dig deep into the install manual.  You'll find a section stating that the instrument's RS-232 GPS interface transfer protocol "Does not provide IFR compliant lateral or vertical guidance, therefore all deviation related data presented is for VFR operations only."  There is the rub!

However, one thing in its favor is the ability to function as a transponder controller for their TailBeaconX.  The TailBeaconX is both a Mode S Transponder (ADSB-out) and a WAAS GPS source.  So if you also need ADSB you can by buy both in a bundle for $4,600.  I point this out because I have the aforementioned King KT76 transponder living on borrowed time, that is interfaced with an older uAvionix skyBeacon TSO.  If the king dies tomorrow, I am grounded.  BUT, I can buy the $4,600 bundle and trade in my skybeacon for an eye-popping $1,200 rebate on the purchase price.  $4,600 - $1,200 = $3,400!   That is a lot of avionics bang for the buck!

Anyway, I'll leave it there.  Starting to sound like a work at uAvionix!

Sincerely,

Zippy_Bird

[joepilotmooney]

Thanks Zippy, too bad I can't IF to my extant Cent 2B then...otherwise I might go for it. I have their tailbeacon, it's been flawless.

[wombat]

@vik @LANCECASPER and @Utah20Gflyer  have all pointed out basically the same solution.  And they are all basically correct.

 

Look at the model of CDIs you have, and see what GPSs they are compatible with, such as the KLN 89b ($900), KLN 90b, ($450) KLN 94 ($1050) etc.

Also research which CDIs are compatible with those different GPSs, such as the KI 202 ($349), KI 206 ($795), etc.

 

Make sure the GPS you get is compatible with the KLN89 tray.   Don't be afraid of the gray code wiring for the altitude encoder.

The prices I've listed are from about 30 seconds of searching ebay.   Most say "working when removed" so good luck with that.   

 

So if you do most of the work yourself under the watchful eye of an A&P you might be able to get this done for about $1k.    If you sell some of the equipment in the plane that you currently have, that might take it down to $500 or so.

 

I've been at this level of cheapness before and while it works, it can be painful.    Good luck, stay safe, stay legal!

[T. Peterson]

On 4/23/2024 at 7:18 PM, joepilotmooney said:

Just wondering has anyone been looking at or have experience with the Uavionix AV30 instruments??

Due to all the limitations others have noted I would not install it as a primary Attitude Indicator. However I did have one installed as a backup AI, and I have been very pleased. Additionally I use it as an altitude reminder. When ATC clears me to a different altitude I can dial in the new altitude on the AV-30. It’s not an alerter, but I can just glance at it in case I start to wonder, “what was that altitude to which I was cleared??”

I also use it to dial in the barometric altimeter setting. I find it easier to read than my  round dial altimeter. It’s just a good cross check.

Having a backup AI is critical for me. I am simply not comfortable with flying IMC on a single vacuum AI.

[00-Negative]

On 4/23/2024 at 7:18 PM, joepilotmooney said:

Just wondering has anyone been looking at or have experience with the Uavionix AV30 instruments??

I've been looking closely at Uavionix AV30s. They just announced the AV HSI which is available for experimentals and will be for certified in the coming weeks. It will communicate with GPS and autopilot allowing for approaches. Sarasota Avionics is taking preorders now. I read on a forum recently that some folks have flashed their certified AV-30 with the experimental software and are already using the HSI capabilities. Uavionix might be my most affordable option with a straight forward easy-as-can be install. I'm really considering dual AV-30s with Aerocruze 100 AP which I can install myself w/ A&P on my field. I recently got estimates for [Garmin G3x + GFC500 -The Full Monty- $84k]; [3 Garmin GI275 + GFC500 $52k] ; and [Dynon Skyview+ Aerocruze] $75k. I have a GTN650 already in the plane. Not only were the astronomical costs a deterrent, but the downtime for the plane was 6-12 weeks for each. 

I couldn't believe the Dynon + Aerocruze was close to the full Garmin setup in price. 

-David

[vik]

18 hours ago, wombat said:

Look at the model of CDIs you have, and see what GPSs they are compatible with, such as the KLN 89b ($900), KLN 90b, ($450) KLN 94 ($1050) etc.

I see 2 x Kx155 (not 165) installed. This means that the CDIs have built in converters. The above mentioned GPS receivers require a CDI without converter. Several popular models exist from King, Garmin, Collins. All require different connectors/pins to make our life more interesting

 

[vik]

5 hours ago, 00-Negative said:

I've been looking closely at Uavionix AV30s. They just announced the AV HSI which is available for experimentals and will be for certified in the coming weeks.

This is a good news if weeks do not turn into years and if they won't drift like DG version did. 

[vik]

5 hours ago, 00-Negative said:

I couldn't believe the Dynon + Aerocruze was close to the full Garmin setup in price. 

Maybe the installer makes less $$$ off Dynon than Garmin, so the owner has to compensate!

[McMooney]

If you can install the aerocruze, you can install the Dynon, the parts are only expensive, not stupid expensive

[Aerodon]

My vote would be for a GNX375 - combined GPS transponder.  Start with a low cost insta and a standalone, save up for G5's or GI275 later?  Remove and sell the DME and KT76A.

 

 

 

 

[Stanton R]

On 4/25/2024 at 12:35 PM, vik said:

I see 2 x Kx155 (not 165) installed. This means that the CDIs have built in converters. The above mentioned GPS receivers require a CDI without converter. Several popular models exist from King, Garmin, Collins. All require different connectors/pins to make our life more interesting

 

The Garmin 175 355 375 can use a CDI with built in converters, like the KI 209 and 204. 

[Neshi]

Just for reference when looking at the baby step approach.

My costs for the upgrade below $28000 and would have been cheaper if I had it all done in one shot.

 

 

[Mellow_Mooney]

Hey guys,

 

First of all - thanks to everyone for your input. I really appreciate it and it helped me go down various paths that led me to end at the below. 
 

I ended up going with the gps 175 and a gi275. Going to be replacing my heading indicator with the HSI, moving my tach into the place of the horizontal guidance CDI (under my manifold pressure gauge), and removing that horizontal CDI entirely. 
 

so I’ll have the HSI and one CDI with horizontal and vertical guidance. 
 

Appreciate all the help! Just wanted to give everyone an update. Will follow up with pics of my panel soon (hopefully)! 
 

One thing I am curious about as I’m still learning IFR - does anyone know of any reason I should keep the second CDI with only horizontal guidance on my panel? By removing it am I limiting myself from any types of approaches?

 

Thx again,

-Mellow