Avionics questions

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PPC1052

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I recently purchased a 1/3 part of a 1976 Cessna 177B. It has the original avionics, although it is IFR rated. We are looking to upgrade, but have yet to decide what to do. Maintaining IFR rating is mandatory for us. It's in the partnership agreement.

We could go with all new, with the latest and greatest (newest garmin touch screen GPS) for about 30k installed. The downside is, obviously, the cost.
We could try to go used. Just looking for dual nav/coms, with indicators, glide slope, audio panel, mode S transponder (all bendix/king), with a blind encoder, looks like it would be right around 10k just for the equipment, and I have no idea what it would cost to install. I think I could upgrade one of the nav/coms to something like a used garmin 430 for an additional 4k (or 6k for waas, if available).

I would really like to give myself a good general education about all these issues so I can make an educated decision about which way to go. Is there some resource that I can use to help educate myself about avionics, which models/brands are good, compatibility issues, what all the requirements are to make the system functional, etc.?

Because the cost would be split three ways, it may be that it is worth it to us individually to buy a little more functionality, even if the total package cost would seem unreasonable relative to the airframe. For example, if an all used system installed is 15k, my share is 5k, but if the total cost is 30k, my share is 10k. Maybe it would be worth it to each of us to spend that extra 5k to get the upgraded functionality. On the other hand, it is still 5k.

What do you guys think about which way to you would go, and why?
 
OK, we know you want good IFR functionality, which basically means at least:
- dual comms
- dual navs, one with ILS
- transponder
- audio panel

Exactly what radios are in the panel now -- including make and model? Just what is your budget? Sounds like you'd be willing to put $15K in the panel, but not $30K. Are you in an area where Mode S TIS would have value? Given the approaches where you fly, is an approach GPS an important capability?
 
Cap'n,

It's not that I am not unwilling to pay 10k, it's just that I only want to do that if it makes sense. Granted, that's a pretty vague requirement, and ultimately, I have to make that call myself. But I am ill equiped to make that call based on my current knowledge base.

The radios in it now are:
2 ARC RT-328T nav/coms;
2 indicators;
1 Cessna ARC 300 transponder (RT-369A) with optional altitude encoder;
1 Cessna 400 Marker Beacon (R-402A);
Cessna Navomatic 200A autopilot (AF-295B );
Cessna 300 ADF (R-546E) w/ indicator (although this seems not to work);
I think it has the Cessna 400 Glide Slope reciever (R-443B )

As to the audio panel, I don't exactly know the specifics. The marker beacon lights are on the audio panel. I think that the 400 Marker Beacon refers to a receiver, but not the audio panel-- but I am not sure.

As to your other questions, I cannot answer for certain. I am in the Indianapolis metro area. I am not instrumented rated myself, yet.
 
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About six years our parternship replaced an old radio and Piper wing leveler with a Garmin 430 and an STEC heading following autopilot, it cost about $10K installed. That would probably be a bit more now.

You could save a bit by getting a cheaper King KLN-94 and an iPad. You're going to need a reliable radio (unlike what you have now) and an IFR GPS if your members do much serious cross country IFR flying.

One VOR/ILS is enough, if you have even a vfr gps you don't need a second VOR receiver.

You probably ought to budget to replace that old transponder also.

Don't worry about the ADF, you don't need it. A good audio panel is very nice to have, but you can limp along with what you have if you have to.
 
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JimNtexas said:
About six years our parternship replaced an old radio and Piper wing leveler with a Garmin 430 and an STEC heading following autopilot, it cost about $10K installed. That would probably be a bit more now.

You could save a bit by getting a cheaper King KLN-94 and an iPad. You're going to need a reliable radio (unlike what you have now) and an IFR GPS if your members do much serious cross country IFR flying.

One VOR/ILS is enough, if you have even a vfr gps you don't need a second VOR receiver.

You probably ought to budget to replace that old transponder also.

Don't worry about the ADF, you don't need it. A good audio panel is very nice to have, but you can limp along with what you have if you have to.
Click to expand...

The only reason i could fathom to install a KLN94 would be if there is an existing KLN89B in the plane and you want the upgrade and don't have to eat the installation cost. Those KLN94s are still gong for damn near what a 430 is and don't have anywhere near the capabilities.
 
Can the new touch screen do anything the 430 can't ? The 430 seems like a proven piece of equipment. Also, a lot more pilots you fly with will know the 430 and how to use it.
 
I put in a GNS430W and an SL-30 last spring in place of original Collins coms & navs. Expensive but the WAAS GPS is very nice to have as primary nav under IFR. The SL-30 is a bit overkill in hindsight. It performs well and conserves panel space so I was able to put the DME in the center stack rather than on the right side. Dunno if it was worth the couple AMUs extra though.

Also put in a PMA8000B audio panel. Compared to the other stuff, the audio panel was chump change so it was pretty much a no-brainer. It's pretty much a toss-up between the Garmin and PS audio panels - push the button(s) and they work. The shop also totally rewired the audio plugs and the system is very quiet now (it used to pick-up the strobes). Getting rid of the excess noise in the audio system was definitely worth it.
 
Mike5250 said:
Can the new touch screen do anything the 430 can't ? The 430 seems like a proven piece of equipment. Also, a lot more pilots you fly with will know the 430 and how to use it.
Click to expand...

I have used the 430, but not the 650. The 430 is what was in the plane I did my private in. It's not user friendly, but you can certainly learn to use it just fine. From the information I have reviewed, I believe (I have no hands on experience) the new Garmins are much more user friendly, and therefore lessen the work load. But, of course, the 430 is quite useful, too.

Looking at Gulf Coast, the cost for a new GTN 650 (WAAS) is about 10.3k, compared to a used 430 (WAAS) for about 8.5k, or a non-WAAS for about 6.3k from some place like Bennet Avioincs. Perhaps, there are cheaper places to find good used avionics. (Please let me know!) But, just using these data points, comparing apples to apples (both units with WAAS), if my 1/3 share of the difference in cost really is just $600 I would rather go with a brand new GTN 650 over a used 430.

The real question in my mind is do we just put in used dual nav/coms-- something like a Bendix/King kx-155--, and keep it relatively cheap at about 10k plus install (including replacing the necessary indicators, audio panel, and transponder), or do we go the whole way with a brand new Garmin stack with GTN 650.
 
PPC1052 said:
Cap'n,

It's not that I am not unwilling to pay 10k, it's just that I only want to do that if it makes sense. Granted, that's a pretty vague requirement, and ultimately, I have to make that call myself. But I am ill equiped to make that call based on my current knowledge base.

The radios in it now are:
2 ARC RT-328T nav/coms;
2 indicators;
1 Cessna ARC 300 transponder (RT-369A) with optional altitude encoder;
1 Cessna 400 Marker Beacon (R-402A);
Cessna Navomatic 200A autopilot (AF-295B );
Cessna 300 ADF (R-546E) w/ indicator (although this seems not to work);
I think it has the Cessna 400 Glide Slope reciever (R-443B )

As to the audio panel, I don't exactly know the specifics. The marker beacon lights are on the audio panel. I think that the 400 Marker Beacon refers to a receiver, but not the audio panel-- but I am not sure.

As to your other questions, I cannot answer for certain. I am in the Indianapolis metro area. I am not instrumented rated myself, yet.
Click to expand...

IMHO, replace the 2 Cessna (ARC) nav/coms with MX replacements, and remove the ADF and replace it with a GPS of your choice. ARC transponders were the only reliable product they made. I'd leave it alone until it no longer worked, then up grade.
 
Tom-D said:
IMHO, replace the 2 Cessna (ARC) nav/coms with MX replacements, and remove the ADF and replace it with a GPS of your choice. ARC transponders were the only reliable product they made. I'd leave it alone until it no longer worked, then up grade.
Click to expand...

By MX, do you mean a TKM MX 300? Interesting. I didn't even know what that was, but you are correct. That would make more sense than trying to wedge a bendix/king nav/com into that space. I like this idea if we are going cheap, but functional. Thank you!

Looking at a description that shows "no installation cost," could this be a do- it-your-self job, except for weight and balance up-date?
 
PPC1052 said:
The radios in it now are:
2 ARC RT-328T nav/coms;
2 indicators;
1 Cessna ARC 300 transponder (RT-369A) with optional altitude encoder;
1 Cessna 400 Marker Beacon (R-402A);
Cessna Navomatic 200A autopilot (AF-295B );
Cessna 300 ADF (R-546E) w/ indicator (although this seems not to work);
I think it has the Cessna 400 Glide Slope reciever (R-443B )
Click to expand...
The old Cessna ARC radios. Oy. I see why you want new ones.

If I were tricking out that plane right now, I think what I'd like to do is lose all of it and install the following:
  • Garmin GTN650 GPS/nav/comm
  • Garmin SL30 nav/comm
  • Garmin GTX327 transponder
  • Garmin GMA340 or PS Engineering PMA8000B audio panel
That's about $25K, but it will give you full, reliable, modern IFR capability including WAAS GPS. If you want to cut cost some and the #2 CDI is working OK, you could skip the SL30, leave in the tray from the RT-328 and the second ARC CDI, and slide a TKM/Michel MX-300 into that tray -- that would save about $4K.

Another money-saving option is to find a Garmin GNS-430W on the used market, and have that installed instead of the new GTN650. That would probably save another $3K. Likewise, a used KX-155 for the #2 radio might save another $2K over the SL30.

On the high side, installing a GTX330EX extended squitter Mode S transponder would have you ready now in preparation for the ADS-B-out requirement in the Indy Class B starting in 2020 as well as giving you Mode S TIS traffic data on your 430 or 650 display right now. That would cost an extra #3K.

So, at the bottom end, a panel that ends up like this:
  • Used 430W
  • MX-300
  • GTX327
  • GMA340/PMA8000B
...would probably be down nearer $15K and provide great capability for IR training and routine IFR ops.

As to your other questions, I cannot answer for certain. I am in the Indianapolis metro area. I am not instrumented rated myself, yet.
Click to expand...
The real question is whether the airports to which you would expect to want to fly have enough VOR/LOC/ILS approaches that don't require ADF (or GPS as a sub for ADF) for you to be comfortable without GPS (especially since the ADF is dead already). Talk that over with your partners; if they are already instrument rated, they should be able to give some insight.
 
JimNtexas said:
One VOR/ILS is enough, if you have even a vfr gps you don't need a second VOR receiver.
Click to expand...
While it would be legally sufficient, you are not going to enjoy IR training or routine IFR operations with only one VOR/ILS and no other IFR nav radio.

Trust me on this -- I've done it myself and seen folks try.
 
PPC1052 said:
By MX, do you mean a TKM MX 300? Interesting. I didn't even know what that was, but you are correct. That would make more sense than trying to wedge a bendix/king nav/com into that space. I like this idea if we are going cheap, but functional. Thank you!

Looking at a description that shows "no installation cost," could this be a do- it-your-self job, except for weight and balance up-date?
Click to expand...

No weight and balance to worry about, it is a slid in replacement, done as owner maintenance, you make an entry saying to removed and replaced yada yada.
 
Mike5250 said:
Can the new touch screen do anything the 430 can't ? The 430 seems like a proven piece of equipment. Also, a lot more pilots you fly with will know the 430 and how to use it.
Click to expand...
Yes, it can, but not enough to make me run out and replace my 530 with a 750. OTOH, the extra features (particularly the ease of use) are probably worth the extra $3K or so it will cost to buy and install a 650 versus a used 430W -- especially when divided three ways.
 
Tom-D said:
No weight and balance to worry about, it is a slid in replacement, done as owner maintenance, you make an entry saying to removed and replaced yada yada.
Click to expand...
Tom is forgetting that the equipment list must be altered, since there's no MX-300 on the list that comes from the factory, and that takes an A&P's signature, but if you revise and reprint the list yourself, your friendly neighborhood A&P will probably sign it free.
 
Ron Levy said:
If I were tricking out that plane right now, I think what I'd like to do is lose all of it and install the following:
  • Garmin GTN650 GPS/nav/comm
  • Garmin SL30 nav/comm
  • Garmin GTX327 transponder
  • Garmin GMA340 or PS Engineering PMA8000B audio panel
That's about $25K, but it will give you full, reliable, modern IFR capability including WAAS GPS. .
Click to expand...

The aircraft I'm annualing next week has had that stack installed at the local big av shop at BFI. bottom line ready to shoot the approach, was $37k.
 
Ron Levy said:
Tom is forgetting that the equipment list must be altered, since there's no MX-300 on the list that comes from the factory, and that takes an A&P's signature, but if you revise and reprint the list yourself, your friendly neighborhood A&P will probably sign it free.
Click to expand...
Agreed. but if the other items are installed/changed out there will be other people doing the paper work to make it legal.
 
Ron Levy said:
I'd like to see the full work order on that one.
Click to expand...

I did too, and he showed me the bill, pretty much pull every thing out, clean up the wire harness, and install all new, pretty much as you listed, plus an ELT.

cost of equipment and labor is sky rocketing.
 
The GTN750 is much better than the GTN650. I'd rather have one GTN750 than two GTN650s. The user interface is much better on the GTN750, graphic flightplanning is practical, and the map is great, whereas the GTN650 has an awkward user interface and too small of a map screen for my taste. In order of preferences, I would rather have a GTN750 over a GNS530W over a GTN650 over a GNS430W over a GNS530 over a GNS430 over a KLN94 over a KLN90B over a KLN89B over a Loran.
 
Ron Levy said:
If I were tricking out that plane right now, I think what I'd like to do is lose all of it and install the following:
  • Garmin GTN650 GPS/nav/comm
  • Garmin SL30 nav/comm
  • Garmin GTX327 transponder
  • Garmin GMA340 or PS Engineering PMA8000B audio panel
Click to expand...
I have a quote for essentially this for about 29k. The quote includes replacement indicators. I presume that the new Garmin equipment will not work with the old indicators, correct?
 
PPC1052 said:
I have a quote for essentially this for about 29k. The quote includes replacement indicators. I presume that the new Garmin equipment will not work with the old indicators, correct?
Click to expand...
I honestly don't know, but I can't see the point of saving that small amount of money and keeping the two crappy old ARC CDI's even if they would work. And if you folks pony up for that package, I gua-ron-tee you won't regret having done it after you've flown it IFR a while.;)
 
Ron Levy said:
Tom is forgetting that the equipment list must be altered, since there's no MX-300 on the list that comes from the factory, and that takes an A&P's signature, but if you revise and reprint the list yourself, your friendly neighborhood A&P will probably sign it free.
Click to expand...

The orignal POH has a handy equipment list that shows the weight as well as the moment for the radios. (each one is 6.9 lbs, at 68.0 arm in.) It shouldn't be that hard to subtract the difference in weight for the new equipment. The new empty moment shouldn't be too hard, either. Can the weight and balance just be updated mathmatically rather than actually weighing and balancing? If so, does it require an A & P to do this?
 
PPC1052 said:
The orignal POH has a handy equipment list that shows the weight as well as the moment for the radios. (each one is 6.9 lbs, at 68.0 arm in.) It shouldn't be that hard to subtract the difference in weight for the new equipment. The new empty moment shouldn't be too hard, either. Can the weight and balance just be updated mathmatically rather than actually weighing and balancing? If so, does it require an A & P to do this?
Click to expand...
Yes, and yes. However, if the weight of the new radio is within one pound of the weight of the old radio, and it is put in the same tray, the FAA considers the change "negligible," and the empty W&B data do not have to be updated by either math or weighing. The TKM radios fall within this limit, so no W&B change is required for a slide-in/slide-out replacement of an OEM radio with a TKM radio.
 
So, I really could order 2 units over the internet, pop them in myself, get an A & P to sign the updated equipment list, and (fingers crossed, no glitches) go flying?
 
PPC1052 said:
So, I really could order 2 units over the internet, pop them in myself, get an A & P to sign the updated equipment list, and (fingers crossed, no glitches) go flying?
Click to expand...
You missed putting the radio swap in the airframe log and signing it yourself, but yes, pretty much so.
 
Cool. Preventative maintenance includes:

(31) Removing and replacing self-contained, front instrument panel-mounted
navigation and communication devices that employ tray-mounted connectors that
connect the unit when the unit is installed into the instrument panel,
(excluding automatic flight control systems, transponders, and microwave
frequency distance measuring equipment (DME)). The approved unit must be
designed to be readily and repeatedly removed and replaced, and pertinent
instructions must be provided. Prior to the unit's intended use, and
operational check must be performed in accordance with the applicable
sections of part 91 of this chapter.

14 CFR 43, Appendix A

I presume the check they mean is 14 CFR § 91.407.
 
I talked to one of my partners about the Michel TKM MX 300 radios. We are going to try to get some information about them from a avionics specialist to see what his opinions of them are.

Have any of you all used them? What are your thoughts? Are they decent? Would we be happier with the Narco verison designed to fit the same tray?
 
PPC1052 said:
I talked to one of my partners about the Michel TKM MX 300 radios. We are going to try to get some information about them from a avionics specialist to see what his opinions of them are.

Have any of you all used them? What are your thoughts? Are they decent? Would we be happier with the Narco verison designed to fit the same tray?
Click to expand...
I put TKM MX-11's in two previous planes which came with Narco Com 11's, and wouldn't change that decision -- very good digital flip-flop radios, much better than the Narco's they replaced. No way I'd put another old mechanical Narco in the same hole, especially since Narco is out of business and parts support is a problem. Of course, you're still stuck with the original Narco CDI (TKM doesn't make a replacement for that), but half a loaf...
 
PPC1052 said:
I talked to one of my partners about the Michel TKM MX 300 radios. We are going to try to get some information about them from a avionics specialist to see what his opinions of them are.

Have any of you all used them? What are your thoughts? Are they decent? Would we be happier with the Narco verison designed to fit the same tray?
Click to expand...

I've never had any problems with any MX equipment, but many times old wiring harnesses us problems. If what you have now is working, that should not be a problem.

I don't believe there is any Narco equipment that will drive the Cessna ARC heads. pin out is different ( I think)
 
Tom-D said:
I've never had any problems with any MX equipment, but many times old wiring harnesses us problems. If what you have now is working, that should not be a problem. We might also just replace the audio panel just to make sure.
Click to expand...

Thanks. If we do go MX, we will probably have an avionics specialist do the install to trouble shoot any connections, and make sure we don't have any problems.

I flew her this weekend and the radios worked without any hitches. I have been trying to trouble shoot a problem with the number 2 nav/com. I have it down to two issues: 1) operator error or 2) equipment malfunction.

I only have 6.5 hours total in this plane, and only the last 1.5 have I been the primary or sole operator of the radio. My CFI probably did too much for me in operating the radios during my check out for the insurance. But I think I understand how to operate the system now. So, we will see if the problem is 1 or 2 above.
 
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PPC1052 said:
I talked to one of my partners about the Michel TKM MX 300 radios. We are going to try to get some information about them from a avionics specialist to see what his opinions of them are.

Have any of you all used them? What are your thoughts? Are they decent? Would we be happier with the Narco verison designed to fit the same tray?
Click to expand...

I have a GNS430 and a TKM MX 300 in my plane, and the TKM is just as clear and powerful as the 430 radio. The MX 300's NAV receiver is better than the 430's NAV receiver (picks up stations farther out) but I don't know if that's due to antennas, coax, or the units themselves.

I'm very happy with my TKM MX 300, with one small beef... It is wider than most boxes that are designed for the center stack. So the center stack must be 1/2" wider, resulting in gaps on each side of your Garmin equipment, STEC autopilot (55, 55x), or King radios, etc. Here's a picture to show you what I'm talking about:

6833.jpg
 
JohnAJohnson said:
I'm very happy with my TKM MX 300, with one small beef... It is wider than most boxes that are designed for the center stack. So the center stack must be 1/2" wider, resulting in gaps on each side of your Garmin equipment, STEC autopilot (55, 55x), or King radios, etc. Here's a picture to show you what I'm talking about:
Click to expand...
The MX-300 is designed to replace the ARC radios, which are decidedly different. If I were putting an MX nav/comm radio in my panel as a new install rather than a slide-in replacement, I'd put in the MX-12, which is designed to replace the Narco MK12, and thus is standard size.
 
PPC1052 said:
Thanks. If we do go MX, we will probably have an avionics specialist do the install to trouble shoot any connections, and make sure we don't have any problems.

I flew her this weekend and the radios worked without any hitches. I have been trying to trouble shoot a problem with the number 2 nav/com. I have it down to two issues: 1) operator error or 2) equipment malfunction.

I only have 6.5 hours total in this plane, and only the last 1.5 have I been the primary or sole operator of the radio. My CFI probably did too much for me in operating the radios during my check out for the insurance. But I think I understand how to operate the system now. So, we will see if the problem is 1 or 2 above.
Click to expand...

If your ARC equipment is working why change to the MX300? you gain nothing. I'd not change any thing until I must, because the ARC 300 is not worth a new fuse, but if it's working don't fix it.
 
Ron Levy said:
...but I don't know about availability now that Narco's belly-up, and I wouldn't want to have to get one fixed.
Click to expand...

I know this is a different issue, but now under the new rules the FAA must supply you with the info to fix the now debunk Narco products.

but why would ya?
 
Tom-D said:
If your ARC equipment is working why change to the MX300? you gain nothing. I'd not change any thing until I must, because the ARC 300 is not worth a new fuse, but if it's working don't fix it.
Click to expand...

1) no flip flop
2) transmission/reception can be static-y or weak
3) ease of use-- You have to manipulate two dials as well as flip a toggle for .25 or .5 channel increments
4) may have a problem with Nav/com 2 dependability, although it could be me, the audio panel, or something else.
 
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