Autopilot @ GPS

[William Mattson]

I am looking to add an autopilot and replace GPS at the same time. One avionics shop has a used 530. What I don't understand is he said it is good for IFR enroute non precision and waas approaches. The waas approaches I understand, but have never heard of non precision enroute.

Thinking of using this with a STEC 30 with the GPSS. Is there any reason the GTN 650 would be better or worse?

Thank you,

Bill

[9089P]

I have the Stec 30 and 430W combo with gpss and it works perfectly for us. A 530W does it all so not sure what the avionics guys is saying. Definitely get the gpss, it makes the holds, missed, and the like so much better.

Don

[Charles Schefer]

Bill, regarding "non precision enroute"... I didn't hear the words you did, I only read what you wrote but when I read it I interpreted it as "enroute navigation" and separately "non-precision approaches" ie two different things...

A GPS must of course be certified for IFR in order to used for enroute nav under IFR where the GPS is the primary source of Nav. You must also have an alternate form of Nav available (eg VOR) but I believe under the AIM a WAAS GPS alleviates this requirement.

One thing to watch out for... In order to be certified as an IFR install there must also be an annunciator on the panel in the pilots field of view that tells whether the mode of Nav is GPS or VLOC. For instance on the 530 there is an indicator on the screen but that is NOT good enough for IFR cert of the install. There must be an annunciator on the HSI or VOR head or within 3" of it. Be sure to ask about this.

- Charles

[bernard nowlen]

I have a 430(non waas) installed in my pa-30 and the paperwork says it's certified for ifr enroute and non precision approaches. I do not have a seperate annunciator to indiate whether i 'm getting gps/vor/loc data to the cdi in the hsi .
I think that requirement went away as i used to have a seperate annunciator on the glare shield with my kln 89 back in the 90's. bernie

[Charles Schefer]

It didn't go away Bernie. I ran into this same issue with my GNS-480 waas. My installation is currently VFR only. The only reason for that is the VOR head does not have any internal indication as to whether it is in VOR or GPS mode. It's kind of silly since there is an annunciation on the lower left hand part of the screen of the 480 itself saying what mode it's in and that is just 5" from the VOR head but legally it's not adequate. The reg requires that there be an indication within a certain distance from the instrument you are navigating from (VOR head / HSI). I don't know the spec distance - I think it's like 3" but you could ask your avionics shop.

If you have a Garmin VOR head it will have the annunciation within it. Check out their website and you will see what I mean. A little light up "GPS" or "VLOC" will display inside the unit.

In my case, to certify the Garmin as installed for IFR I would have to spend $1K adding an annunciation to the panel. Since I plan to install an Aspen Pro PFD which will have an annunciation built in I decided to leave it as it is for now otherwise that $1K would be throw away. Trust me I looked into this extensively because I felt mine should be an IFR install but legally it's not. The reg is clear that the instrument you are using (VOR/HSI) must have an annunciation within close range showing the nav mode selected.

- Charles

[9089P]

I believe that Charles is correct. I have the Garmin nav head and the only issue for me was to get is close enough to the 430 when we did the install. As Charles says it is silly as the 430 also has an annunciation in the lower left corner showing the nav source.

Don

[Kristin Winter]

I did the 480 installation and just installed a small STACO switch to the upper left of the panel to meet the requirement for annunciation. See photo. Must less than 1 AMU

Kristin

[bernard nowlen]

According to my "avionics guy",for ifr ops,if the left edge of the bezel of the 430/530 to the center of your scan,
which assume means the attitude gyro is less than11.8" a seperate annumnciator for gps/vor/loc is not required."
If it's betwen 11.8" and 13.41"you need a basic annunciator which shows what is going to the hsi such as a md 41 (vor/loc/gps). If the distance is greator than 13.41" you need annunciators for all modes of operation. Vor/loc/gps/msg/app/term/enroute/wpt etc that are displayed within your scan area (what ever that is) and i bet it's open to interpetation.

[Kristin Winter]

Bernie,

I recall that there was a two tiered requirement. The installation manual for the GNS-480 called out which annunciators were appropriate. The factory center stack installation on a Twinkie allowed me to use the basic annunciator and called out this little STACO switch that I show in the attachment. Needless to say, it was much easier to fit that little guy in the panel than some big thing from Mid-Continent.

[VANBLADEREN]

Bill, I would like to make a case for the GTN series over a used GNS 430 or 530 and especially the non was GPS.
The GTN offers the following:
1. New radio with warrantee.
2. Precision WAAS approaches
3. Completely new simple programing.
4. GTN has features not found on GNS Radios
5. A current production radio which will be support many years into the future.

GNS 430-530
No warrantee
awkward programing
Any repair to the GNS is $1,000 when sent to Garmin.

I have not found used GNS radios to be a good value especially with the high price of USED GNS's

jvb

[William Mattson]

Thank you.

I'm not IFR yet hope to soon, but I want it set up correctly. It's amazing the levels and layers of details one must concern themselves with. Just hoping to educate myself enough to ask good questions.

Bill

[Charles Schefer]

A quick comment regarding support for the GNS-480 (i.e. the Apollo CX-80). I was on the phone with Garmin today regarding updates and I asked about future support for the 480. Garmin's answer was that it will continue to be fully supported for a minimum of 8 more years. They told me that they have some government contracts which require support for the 480 and those contracts require at least 8 more years support. I realize that like the 430 and 530, support may be expensive and there may be a flat fee for anything this is wrong (like the example Pat gave on this or another thread regarding fixing a knob on the 530). But nevertheless if you have a 480 like I do you don't need to worry about Garmin flat out refusing to support it at all. At least not for at least 8 years...

- Charles

[Ron B Keil]

Bill,

I don't understand the comment about non-precision enroute. If the GNS530W is installed in accordance with the STC installation manual, the 530W is capable of all Precision Approaches, all GPS approaches with vertical guidance (WAAS) approaches and RNAV point to point enroute navigation, as well as Victor Airway navigation. It is also capable of Arrival Procedures and departure procedures with transitions. Course reversals including procedure turns and holds, as well as missed approach guidance is provided and with GPS Steering will command the auto-pilot to fly these procedures. I tell my wife that I can fly by just pushing buttons, and no need to touch the yoke except for take-off and landing. (This may not keep your skills up but the system is capable if you need it.)

As to annunciation, the Garmin GNS530W STC installation manual provides guidance for installation:

"In accordance with AC 20-138A, for IFR GPS installations the 500W Series unit must be mounted in the aircraft manufacturer’s approved location or other FAA approved location, and the required CDI/HSI must be mounted in the primary field of view. CDI/HSI navigation source selection annunciation must be on or near the affected display and any additional annunciations must be mounted within the normal field- of-view. An FAA issue paper was written to clarify the TSO-C146a annunciation requirement of “on or near the affected display”. This issue paper said, in order to preclude the need for external source selection annunciations (i.e. using the annunciation within the 500W Series unit), the source selection annunciation displayed on the 500W Series unit must be within 13.856 inches of pilot view centerline. If the CDI is to the left or right of centerline, it must favor the same side as the 500W Series unit placement (i.e. typically the radio stack is on the right of the pilot’s view centerline, so the CDI should be on the right side of the basic primary flight instruments). A CDI/HSI with a built-in annunciation may also be used in lieu of a separate external annunciator to satisfy the source selection annunciation requirement. In addition, any required GPS navigation annunciations must be within 16.805 inches of the pilot view centerline. If the 500W Series unit display is within this area, then no external GPS navigation annunciations are required".

According to this guidance, if your HSI is centered with the Yoke and you have a center stack for radio mounting, in our Comanche's the annunciators on the GNS530W should suffice.

Ron Keil

[Charles Schefer]

Ron,

Thanks for this post - I am going to pull that AC and discuss with the local avionics shop at my field. Based on what you posted it seems to me I might be able to get my installation certified IFR as is without spending a bunch more on extra (and IMHO unnecessary) annunciations. However Kristen commented on a 2-tier requirement (maybe covered in that AC you reference?) and I do know the avionics shop I previously consulted in Illinois (not my home field) was clear that an extra annunciation was required. I'm going to look into this again - thanks for the post.

- Charles

[Kristin Winter]

Charles,

The two tier requirement was from the GNS-480 installation manual, but it might reflect something in the advisory circular.