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Instrument panel critique

leok

Well Known Member
The photo shows the IP layout so far. Since I haven't purchased the instruments or cut holes, I thought this might be a good time to post and let others tell me what they think. I recognize everyone has their own favorite layout, so in the spirit of learning, I appreciate all feed back. It is intended to be IFR capable.

By way of explanation, I have chosen to go with Garmin G3X and all Garmin supporting cast. Instead of a GTN650 or 750 I plan on a remote mounted GPS20A (ADSB WAAS certified position source) feed to ADSB out, both MFDs with seperate GNC255a nav/com and GTR200 com radios. The cost is about $4K less total and I don't need another screen. I also wanted to leave space in the lower center stack to mount an ipad (removable and exchangeable as technology changes).

20160424_210828_zpsnat6lfs7.jpg


All of the switch plates are laser etched second surface (etched from the back in black coated clear stock) and backlit.

Leo
 
You will technically be IFR capable with this setup, but will only be able to do VOR and ILS approaches. The GOS position source will cover your 2020 requirement for ADS-B, but don't confuse that with the need for an IFR GPS Navigator. You will be much better off with a GTN-625 or 650 instead of the Nav radio. With the money you are spending on the airplane overall, this is peanuts, IMHO. You will be considered by most people not IFR capable without an IFR GPS.

As for layout, I have don't this many times, and have flown many RV-10's. The right hand panel will be slightly better than useless to the pilot. It is simply too far to the right. If you keep it there, unless you expect to do a lot of flying from the right seat, you would be much better off removing that screen and spending the extra money on the GTN-625 or 650. I understand the desire to by symmetrical, but that is a long way to reach with your hands or your eyes.

I recommend putting the G3X screens right next to each other with the radios along the bottom and/or top of the panel. With the new glass panels, keeping the traditional radio stack is both not as important, and not as practical. You can also move the left screen further to the left. I can't tell what you have to the left of the left screen, but you should be able to do whatever that is in a smaller format to allow for better use of the panel real estate for the more important items.

Just my $.03.
 
I'm with Jesse. I would forego the paint job before I went without a GTN650 if IFR is your mission. You're going to want the coupled GPS approaches at your fingertips. If it were me, I would put a GTN in the stack and remote mount the second com, controlling through the touch.
 
Two MFDs with independent ADAHRs powered from separate busses.

What's your plan when one goes bad in IMC? Which one is the correct one?

This is why most folks use a small EFIS from another manufacturer. Not only does it provide the tie breaker, it also has independent code in case there is a software issue that takes out both screens.

The good news is that there are plenty of options available from all manufacturers.
 
I would place the AP controller (GMC 305/7) at the top of the stack.

Not only do I think this is a user friendly location but the device is also very shallow (doesn't interfere with Ribs behind panel) and does not rest in a mounting tray. Its nice to be able to stack your trays on top each other but if the GMC is in the middle, you'd end up with a gap between trays. Make sense?
 
Some opinions

REally cool that you ask for ideas! I normally lay out the panel and then blow it up to full size and sit in a chair in front of it and pretend I am flying (making noises only when no one is looking of course!).

First, as mentioned, don't short yourself on an IFR navigator. You don't need to spend a lot of buck on large screen navigators, as you will hardly ever look at them since all of the information is on the screens, but you will need it for IFR procedures and approaches.

For my airplanes I always put both screens on the left side and the radio stack further to the right. It makes really good use of the screen real estate. Otherwise, the screen on the right side is not used much, and you find yourself configuring the pilot's side with too much clutter so you can see EFIS/MAP/Engine data. The RV10 is much bigger than the other SBS RV's, and it is quite a reach to the screen on the far right side. When someone does fly from the right side, it is easy to configure the pilot's right screen for flight information and the right seat pilot can use it just fine.

I think the autopilot controller should be at the TOP of the radio stack so either pilot/non-pilot can get to it. I always brief my non-pilot wife on how to engage the autopilot should anything happen to the main pilot. :) I like for it to be within reach of both seats.

Just some thoughts.....

Vic
 
Hello Leo,

You have a great start there and we appreciate you choosing Garmin products for your RV-10!

You have obviously put a lot of thought into this and have made some good decisions, but we want to make sure you are aware of all the options.

First, while the GNC 255A has a street price of around $3,900 and is attractive because it includes both COM and NAV radios, when the cost of a GPS 20A ($845) with GA 35 antenna ($309) are added, you end up at ~$5,050 which puts you close to the special price of $5,495 (including antenna) which we sell a GTN 625 for when purchased with a G3X or G3X Touch system, which has much more IFR capability.

The GTN 625 not only supports flying legal IFR enroute, but of course allows you to fly all those great LNAV+V and LPV approaches, which greatly exceed the number of ILS approaches available in the U.S. Many of the smaller airports that EABs often use don't have an ILS approach, but do have an LPV approach. As a bonus, the GTN 625 also serves as the 2020 compliant position source for your $2,199 GTX 23ES transponder to get you all ready for 2020.

As others have mentioned, you might consider installing the GMC 307 with dedicated heading and altitude select knobs. It also has larger buttons than the GMC 305 which I really like.

eJE049jaBu8_RuTFOcg9QxgpjyuFXnMPr72IIkcvJQA=w536-h184-no


It is a little hard to see which audio panel you have in your stack, but please consider the new GMA 245 Bluetooth capable audio panel.

Front.jpg


In the event you do decide to install a backup instrument, please consider the new G5. As explained in this posting, the G5 was designed from the ground up to be the best electronic flight instrument on the market including a great deal of independence and dissimilarity from your G3X system. It is not necessary to purchase a backup instrument from a different vendor and give up on the tight integration offered by the G5 if the instrument is properly designed.

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0s9GHPqfaKb30_hNOn5H2pKkSR06eBemRx1nyrgQ1ZSYSUjjrqDX72VejKzo3UMrvKTOvfj8NgL3DPLFQqPAT1WB6IJRQ0H53uKTAfmIVYS81URRIECJaZnYVhoICxsqd5id2PRARjRuWaEYr6n842taP5YmGMm4QNvOe0fcYiNyx5APlneRS9GlbPYu3aEsGcj3_wLAVqsqYcZgmsdZ7A5eu5LtkyNqpekXreFDAWWQMiOHdpeIpa6NjvSkRjGFbhxMZ5YaxfktdvyIMr0Zk343k_4ZRo9s7IsRE93711OuBxZwxsyr5mLu_eWdE6c0iN4GQ09UdF3FawZQ0VWuQXCvjv1HXRNtwDdNudv311_JFpdBqliHsMZrUBibssz_JFj82cVU387P0GkNznCjaq9S9KiNX9YhIqs-C-_-dq0Ke1B8d7gOMgGXATJpb6XfmUCiTpUFihYi_yZ2ShIVCgwO79l4TrBt8ZgW9Io87RwMOVP6AIaIJMjNfp70Do7_p1MRrl35UuyU7ntqLTnVRPSw0Aq7zSmTPdmGYjIXrXnsvB5WOJmZSFOs8ID7swpxQR_M=w475-h307-no


Speaking of tight integration with G3X, those installing a G5 can consider using this as their backup ADAHRS instead of a second GSU25 ADAHRS. Just like a GSU25, the G5 can be connected to both the primary CAN bus and wired directly into a serial port on a G3X or G3X Touch display as a backup data path. You can shut down GSU25 #1 and even the CAN bus, and the G5 will still be providing ADAHRS data and even WAAS GPS data to a big display in the G3X system over the RS-232 backup data path. When you have a choice to buy a second GSU25 ADAHRS for $799 or a complete G5 flight instrument with display and GPS for $1,199, it is interesting to consider the latter.

Please don't hesitate to contact us directly if you have any questions.

Thanks,
Steve
 
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You will be much better off with a GTN-625 or 650 instead of the Nav radio. .

As for layout, I have don't this many times, and have flown many RV-10's. The right hand panel will be slightly better than useless to the pilot. It is simply too far to the right.

I recommend putting the G3X screens right next to each other with the radios along the bottom and/or top of the panel. With the new glass panels, keeping the traditional radio stack is both not as important, and not as practical.

Totally agree. My 3rd screen (which is about where your left screen is) is of very little use to me from the pilot's seat. I'd 3rd the notion of putting the PFD and MFD side by side. When I'm setting up for an approach, I've got the both PFD and MFD split, so I'm really using the full real estate of the two high res screens. I wouldn't want to read a plate that far over!

Also, GPS approaches are where things are going. I also agree with the commenters above about the value of the GTN.

I would place the AP controller (GMC 305/7) at the top of the stack.

I read this a lot, and I don't know that I agree. I know that's where most jets locate the AP panel, but I find it really convenient having the AP control panel low and centered on the panel. It's within a few inches of where my hand rests in flight (on my armrest mounted quadrant), and a smooth movement to make when going from NAV to HDG when ATC gives me a clearance with a heading... as opposed to reaching up, and possibly over to the left if it's above the PFD.
 

Leo,

I agree with most of what's been said. I'm very happy with my layout. The IPad isn't referenced much. Nice for the passenger though.

The AvMap Ultra backup EFIS will soon be replaced with a Garmin G5. If I had the extra space of a RV-10, the only thing I would change is an IPad Air in place of my mini, and maybe ($!) a Garmin 725 for a more useful center display.
 
750

Go with a 750 and remote mount the audio panel and transponder. Then you will have all the capability.
 
I read this a lot, and I don't know that I agree. I know that's where most jets locate the AP panel, but I find it really convenient having the AP control panel low and centered on the panel. It's within a few inches of where my hand rests in flight (on my armrest mounted quadrant), and a smooth movement to make when going from NAV to HDG when ATC gives me a clearance with a heading... as opposed to reaching up, and possibly over to the left if it's above the PFD.

It looks like we totally agree with each other, Ed.
 
I had mine at the bottom of my stack and while it was conveniently located just above my throttle hand; I always disliked the head movement of looking down at it.
 
Fantastic and much appreciated feedback.
:D:D:D
I will need to take some time to fully digest the feedback and formulate where I want to go. I absolutely want to the aircraft to be not just technically IFR capable, but a solid comfortable IFR platform as well ..

It also has to look good doing it! :cool:

I am convinced I want to stick with an integrated solution from one avionics supplier. Integration issues and playing nice together are soooo much easier with a single supplier. Since it seems Garmin is the only game in town for IFR GPS and they have the G3X, that is the way I plan on going.

As with all of the great comments so far, any additional comments are welcome.
 
I am convinced I want to stick with an integrated solution from one avionics supplier. Integration issues and playing nice together are soooo much easier with a single supplier. Since it seems Garmin is the only game in town for IFR GPS and they have the G3X, that is the way I plan on going.
e.

Since you are convinced I won't try too hard to change your mind. But, for example, GRT EFIS systems interface just fine with Garmin GPS navigators, Garmin (nee Apollo) nav coms, Trio, TruTrak, and GRT autopilots, many different ADSB receivers, etc. When you lock in one manufacturer you may also be locking in a single, higher than need be, price for some components.

I also second the recommendation for a small, third EFIS, to minimize the chance of a common software error bringing down everything. Normally I'd say a different manufacturer (Dynon, GRT) but Garmin claims the new G5 uses different hardware and software than their main EFIS so you could include that as a possibility.

Edit. As already said, a screen on the far right is pretty much for a right seat pilot.
 
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I am not as far as you, getting there, but I found your post brought up some really neat and very useful dialog and great topics/aspects to think about. I am going Dynon on the displays/txpder/AP/2020/Weather/EMF/com2, but clearly Garmin for the GPS-IFR (likely the GTN 650) I am symmetrical person too and lived/flown a long time with a center-stack of radios....may be time to bust loose and go unsymmetrical in the 10. Good luck with the design and fund raising, your not alone! Cheers, Mike
 
Go with a 750 and remote mount the audio panel and transponder. Then you will have all the capability.

Stick with the 650, you can still remote mount the transponder and control it thru the G3X. And it's a non-certified transponder, so it's cheaper than the one you need to use with the 750.

You can also remote mount the new Garmin audio panel and control that thru the G3x. I'll be installing one of those soon, but I'm going to keep the physical buttons for the audio panel as well. I like volume knobs right at hand vs in a menu.
 
Thanks again for the replies ... as I tell my wife, 'I am convinced, until I am offered evidence that un-convinces me ;)

I do have a question based on one of the responses. Just to level set, I fly a 182RG, 182 fixed, 172 and an Archer on a semi-regular basis. All have Garmin 430s. Some will fly GPS approaches, others not depending on the vintage or presence of the autopilots. I have around 500 hours and have completed about 1/2 of the hours for an IFR in a basic 152 before I decided hold off until later. All of the IFR was on steam gauges. No GPS, so no experience using the GPS in IFR situations. So the question:

In the G3X system the GDU460 MFD has the autopilot function built in with the addition of Garmin servos as I understand the product literature. It also has a non-WAAS GPS assuming the antenna is installed. With the GPS20a installed and feeding the GDU460 it now has WAAS position data .... here is the question ... what role does the GTN625 (or 650) have in flying an IFR GPS approach? I hope this is not a dumb question, but I really don't care since I would really like to better understand how these boxes do their magic! Thanks in advance.
 
It also has a non-WAAS GPS assuming the antenna is installed. With the GPS20a installed and feeding the GDU460 it now has WAAS position data .... here is the question ... what role does the GTN625 (or 650) have in flying an IFR GPS approach? I hope this is not a dumb question, but I really don't care since I would really like to better understand how these boxes do their magic! Thanks in advance.

G3Xpert put it best... As usual...

GTN 625 .... Has much more IFR capability.

The GTN 625 not only supports flying legal IFR enroute, but of course allows you to fly all those great LNAV+V and LPV approaches, which greatly exceed the number of ILS approaches available in the U.S. Many of the smaller airports that EABs often use don't have an ILS approach, but do have an LPV approach. As a bonus, the GTN 625 also serves as the 2020 compliant position source for your $2,199 GTX 23ES transponder to get you all ready for 2020.
 
Jesse, I appreciate your comments and will look at ways to incorporate the feedback. I do like the symmetry of the layout, but hear loud and clear the limited usefulness of the right screen to a left pilot.

The following pic shows the left center section a little better. The center section is raised and so precludes the big screen in the center unless I redo some of the glass work. To the left of the MFD is a switch group for Master, Avionics, E buss, Alternator field, etc... It could be slimmed down a little to give space for a small back up EFIS perhaps. The GPS choice was less based on money, more on the lack of need for an additional screen if I could get the functionality without. So I'll look at more options to see what I like best. The area below the center stack and above the quadrant is open right now to allow a mount for an ipad, but could be used for other purposes .... hummmmm.

20160424_210901_zpsdy1pmchm.jpg


I also appreciate the comments from "the Garmin Expert". The web site can be difficult to understand how everything relates to the other components. (And getting quality time with the experts at Oshkosh can be a real exercise in patience)
Thanks again for the feedback .. my panel will be better for it.
 
Nova,

Got it .. I was too busy wrapping my head around changing up the panel to parse G3Xpert's words better.:eek:
 
In my RV-9A, I've got much the same setup -- dual G3X plus center stack radios. However, on the right side G3X, I've got engines on the outside (far right), then PFD, then a reconfigurable screen inside. This means that each pilot has their own engine gauge display and their own PFD display (the PFDs are not individually configurable, but not a big deal). In my experience, you don't need the right side map or whatever to be full screen, and having it on the inside of the screen makes it plenty readable.

This configuration also means that you can fly the plane from either seat with full capability, and that's important to me, at least.

In this configuration, however, if the right side G3X is selected as full screen, it becomes a full screen MFD, and the the PFD goes away. A very minor nuisance at best.

If I were doing my panel again, I would add a full time fuel pressure gauge (you'll only see fuel pressure when the engine page is displayed), and a voltmeter with a switch so that I can see (selectably) battery and bus voltages. Sure, there are programmable warnings, but if you have a slow decline, the programmable warning won't tell you about it.

Also, be prepared for hefty learning curve if you're going IFR. The user interface has a number of neat design features, but there is a ton and a half of functionality to be learned. My hand flying skills are easily up to the IFR task, but not the button pushing. Yet.

I don't have my panel picture on line so I can't post it here, but PM me and I'll email it to whomever may be interested.
 
In the G3X system the GDU460 MFD has the autopilot function built in with the addition of Garmin servos as I understand the product literature. It also has a non-WAAS GPS assuming the antenna is installed. With the GPS20a installed and feeding the GDU460 it now has WAAS position data .... here is the question ... what role does the GTN625 (or 650) have in flying an IFR GPS approach? I hope this is not a dumb question, but I really don't care since I would really like to better understand how these boxes do their magic! Thanks in advance.
Even if you have a WAAS position source for 2020 compliance, you still need an IFR Cert GPS to legally fly GPS based approaches. You may not use the screen for anything, as it will display them on the G3X, but you must have it for the NAV data. The G3X has the approch plates in it, but it will not sequence the approaches without a IFR Cert GPS driving it. (And this is the same as all the other EFIS vendors).
 
Leo,
As a not-yet instrument pilot trying to design an ifr aircraft, you do not have the advantage of much real world experience. Ask as many ifr pilots as possible for their opinion, but always remember everyone likes what they bought. Ultimately the responsibility falls on you. Some questions to ask:
How much redundancy? 2x? 3x? more?
What are the failure modes? loss of electricity? loss of pitot? Software bug? What are the backups?
Do I 'need' an autopilot (The RV is no where near as stable as a 182)?
And the expensive question: Do I 'need' an ifr approved (TSO'd) gps navigator? What are the options (used, older TSO129 boxes for less than $2K up to the GTN750 and others at well over $10K) and what are the plus and minuses of each? And lots more. Unless money is not important, there will be compromises made, so again, educate yourself as much as possible.
Bob
 
Thanks Bob, learning and getting it right is exactly why I am posting where I am up to this point.

Based on comments it is an easy switch to delete the GNC255 nav/com radio and add in a 625 or 650 GPS. Moving the GTR200 back up radio to a remote also makes sense if I need that for additional room.
Moving the second screen to center is a more difficult proposition. The center section of the IP as it is currently configured fits up to 6 1'2" wide. I can redo the center stack and replace the IP aluminum blank as it is already split, but really need to convince myself I need to make the change. Physically sitting in the plane as currently configured, I can tell it is not optimal as there is head movement to view, but I can easily see and reach. The center IP section is only 7" wide, so doesn't push the right screen as far over as other center sections I have seen. I could go for broke and spring for a 750 to get the large screen. As I think Jesse opined, it is a small chunk of $s in the overall cost of an RV-10. (saying that too many times and it starts to turn into real money! :D )
I do like the addition of the G5 in the center as a back up. I'll likely add that in as well.

Thanks again for all of the great feedback. Much appreciated.
I'll post another pick when I have this all sorted out and let everyone take another shot at me if I still don't have it quite right.

P.S. thanks Ed for emailing the photo of your panel.
Leo
 
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I have a follow up question for those who regularly fly IFR.

The GTN625 recommended earlier in this thread does not have Nav radio or Com functions. So trading off the GNC255 Nav/Com $s for the 625 is also trading off the VOR/ILS approaches for GPS. (I think I am correct here?) Assuming one were to install one or the other, having the GPS approaches appears to give coverage to the greatest number of airports (also with VORs going away) ... the question...

In an aircraft with an IFR mission (as I plan) is it worth the additional cost to step up to the GTN650 (or add back in the GNC255) to have the radio nav functions?

Thanks in advance.

Leo
 
A GPS definitely covers many more airports in the US than a Nav radio does, hands down. If going with one or the other, then definitely the GPS is the way to go.

If you want both the GPS and the Nav radio, it's hard to say. On one side, it would be more redundancy to have a separate Nav radio because if one of the two finals, you still have the other. For simplicity, going with the 650 would be better. From a cost perspective, it is probably about the same.

The "is it worth" question can ONLY be answered by you. It's a cost-benefit issue that will be different for everybody.
 
In an aircraft with an IFR mission (as I plan) is it worth the additional cost to step up to the GTN650 (or add back in the GNC255) to have the radio nav functions?

Thanks in advance.

Leo

The $50 Million (or $5K at least) question! Look at all the posts, and you will see all possible answers.
Option 1, have only GNC255: Lowest cost. ILS approaches still have, generally speaking, lower minimums than anything else (gps-LPV is getting close). Need MB or ADF or GPS for most ILS's. Shut out of gps-only airports. What will you do if this box fails?
Option 2, have only WAAS-GPS: Generally pretty good, but some days only an ILS will get you in. Cannot do an IPC or take your instrument check ride in this plane. What will you do if this box fails?
Option 3, ILS-VOR-GPS in one box (650, etc). What will you do if this box fails?
Option 4, ILS-VOR in one box, GPS in second box. Highest cost.
I'm sure you see my bias. There are lots of other similar questions, such as second power source if primary battery/alternator fails. etc.
 
Thanks Jesse for the amazingly quick reply.

Just curious if those regularly flying IFR with both GPS and radio nav capability use one or the other or both?
 
Regarding the layout and not the equipment installed, I would dump the key switch. Anything that hangs from that key will block the switches below it.

Also think about your hand movement when flying. In particular, think about where you hand has to go in an emergency and during landing. Put the things you need to manipulate close to the throttle. (Landing and Taxi lights, fuel pump, flaps, & trim)

As Vic mentioned, chair fly the panel and move things around as needed. For example, I moved the interior lights and cabin heat way over on the right side of the panel as the passenger can manipulate those.

All the things I need for landing are arrange left to right, on the left side of the throttle quadrant, with the exception of the flap switch. The flap switch is to the right of the throttle quadrant and can be toggled up and down without removing my hand from the quadrant.
 
Just curious if those regularly flying IFR with both GPS and radio nav capability use one or the other or both?

I have and use both. Many destinations do not have an ILS, so the approach of choice is GPS. At the home airport, the ILS minimums are 120' lower than the LPV's so that's my choice (even if ceilings are high, I need the practice).
I cannot remember the last time I did a non-practice VOR, LOC, SDF. And I don't have an ADF.
 
Thanks Jesse for the amazingly quick reply.

Just curious if those regularly flying IFR with both GPS and radio nav capability use one or the other or both?

Only thing I would use radio nav equipment for is shooting an ILS. GPS for everything else. No VOR tracking/VOR approaches for this guy. GPSs will overlay/track VORs more accurately anyway. Always good to have a backup in case GPS goes out, though, I guess. But in my 3K hrs, I've lost GPS one time, and that is when they were doing GPS jamming out by white sands late one night. As for the approach, whichever has the lowest mins. Usually that's the ILS. Operationally, ILS and LPV approaches are about the same, so whichever works best or is available.
 
I hope you noted my caution that, under current rules, you cannot use your airplane for the instrument rating check ride if you go (TSO'd) GPS only. You might want to consider the cost of renting (for both prep and test) a different airplane, vs buying a VOR box for yours.
Edit: I re-read your posts, and realized that you are probably several years away from completion, is this correct? If so, (1) Do not buy avionics now. It's fun to dream, but they change so fast it only makes sense to hold off on avionics until you really are ready to install them - near the end of the build. In this case, I'd suggest you continue to work on yor rating while you build. You'll recover some of tbe cost via a lower insurance premium on the -10. And, with some experience, you'll be in a better position to answer these questions yourself.
 
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I hope you noted my caution that, under current rules, you cannot use your airplane for the instrument rating check ride if you go (TSO'd) GPS only. You might want to consider the cost of renting (for both prep and test) a different airplane, vs buying a VOR box for yours.
Edit: I re-read your posts, and realized that you are probably several years away from completion, is this correct? If so, (1) Do not buy avionics now. It's fun to dream, but they change so fast it only makes sense to hold off on avionics until you really are ready to install them - near the end of the build. In this case, I'd suggest you continue to work on yor rating while you build. You'll recover some of tbe cost via a lower insurance premium on the -10. And, with some experience, you'll be in a better position to answer these questions yourself.

Why can't he use a GPS only aircraft for an instrument rating? One can satisfy all the non precision/precision requirements with GPS approaches, as well as all other required checkride items, with only a GPS.

https://www.faa.gov/training_testing/testing/test_standards/media/faa-s-8081-4e.pdf

Aircraft and Equipment Required for the Practical Test
The instrument rating applicant is required by 14 CFR part 61 to provide an airworthy, certificated aircraft for use during the practical test. Its operating limitations must not prohibit the TASKS required on the practical test. Flight instruments are those required for controlling the aircraft without outside references. The required radio equipment is that which is necessary for communications with air traffic control (ATC), and for the performance of two of the following nonprecision approaches: very high frequency omnidirectional range (VOR), nondirectional beacon (NDB), global positioning system (GPS) without vertical guidance, localizer (LOC), localizer-type directional aid (LDA), simplified directional facility (SDF), or area navigation (RNAV) and one precision approach: instrument landing system (ILS), GNSS landing system (GLS), localizer performance with vertical guidance (LPV) or microwave landing system (MLS). GPS equipment must be instrument flight rules (IFR) certified and contain the current database.
Note: A localizer performance with vertical guidance (LPV) approach with a decision altitude (DA) greater than 300 feet height above terrain (HAT) may be used as a nonprecision approach; however, due to the precision of its glidepath and localizer-like lateral navigation characteristics, an LPV can be used to demonstrate precision approach proficiency (AOA VI TASK B) if the DA is equal to or less than 300 feet HAT.

Is there another reg that supersedes that?
 
Why can't he use a GPS only aircraft for an instrument rating? One can satisfy all the non precision/precision requirements with GPS approaches, as well as all other required checkride items, with only a GPS.

https://www.faa.gov/training_testing/testing/test_standards/media/faa-s-8081-4e.pdf

Aircraft and Equipment Required for the Practical Test
The instrument rating applicant is required by 14 CFR part 61 to provide an airworthy, certificated aircraft for use during the practical test. Its operating limitations must not prohibit the TASKS required on the practical test. Flight instruments are those required for controlling the aircraft without outside references. The required radio equipment is that which is necessary for communications with air traffic control (ATC), and for the performance of two of the following nonprecision approaches: very high frequency omnidirectional range (VOR), nondirectional beacon (NDB), global positioning system (GPS) without vertical guidance, localizer (LOC), localizer-type directional aid (LDA), simplified directional facility (SDF), or area navigation (RNAV) and one precision approach: instrument landing system (ILS), GNSS landing system (GLS), localizer performance with vertical guidance (LPV) or microwave landing system (MLS). GPS equipment must be instrument flight rules (IFR) certified and contain the current database.
Note: A localizer performance with vertical guidance (LPV) approach with a decision altitude (DA) greater than 300 feet height above terrain (HAT) may be used as a nonprecision approach; however, due to the precision of its glidepath and localizer-like lateral navigation characteristics, an LPV can be used to demonstrate precision approach proficiency (AOA VI TASK B) if the DA is equal to or less than 300 feet HAT.

Is there another reg that supersedes that?

In the body of the PTS it says ".....two different non precision approaches using DIFFERENT navigational aides..." . The non precision "gps" approach is the same as the non precision "RNAV(GPS)" approach. The reference to RNAV without the "(GPS)" refers to the VOR-DME based system which can provide navigation along arbitrary paths. (and is practically obsolete). So a TSO145/146 GPS gets you only two of the three required different approaches. (The same is true for IPCs, btw.) I could mention that I will give an IPC in an airplane with only GPS. I hand the pilot a portable VOR receiver, turn off the gps (I say it just quit), and have him shoot a VOR approach. If he can do that, he certainly could do it with an installed VOR, so IMHO this meets the spirit if not the letter of the PTS. Not sure designated examiners have that freedom, though.
 
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Bob thanks for the guidance/advice. Yes, I am at least two years out on the 10. It could be more. Don't want to put a deadline on it because that tends to take the fun out of the process. I will not be purchasing the big ticket avionics until much closer to the end. Probably about the same time I buy the engine and prop, so at a minimum one year.
I am doing a lot of the non-avionics wiring. I have the VPX installed and am working out the various sub-busses and lighting. I am allocating space for the various items, and thus the interest in the avionics. I am not too worried if Garmin comes out with new versions assuming the allocated space and VPX outputs remain essentially the same.

As for working on my IFR. My current thought is to do that training in the 10 for a few reasons.
1. I am flying only enough to feel comfortable and current as a VFR pilot. I know IFR skills would not be well tended with my current level of flight.
2. I do not have access to an aircraft with glass avionics. I would like to train in what I will be flying. I am in a club with four aircraft, all of which are nice, but 6 packs with 430s.
3. Too many demands on my time and attention to truly focus on mastering the IFR material. I will retire in 4-5 years, hopefully, allowing much greater freedom to concentrate and knock the IFR out.

Might all be lame reasons to others, but they wok for me. One thing I can say for sure is that I want the 10 to be capable of meeting all of the requirements for IFR training, IPC etc..
So once again, thanks everyone for the feedback
 
GPS requirements for IFR capability.

Can someone tell me if a certified GPS is required to be IFR legal in an experimental aircraft? Or just a WASS GPS installed?
thanks
 
Can someone tell me if a certified GPS is required to be IFR legal in an experimental aircraft? Or just a WASS GPS installed?
thanks

What do you mean by "legal"? You mean to use the GPS for IFR flight, I presume?

If so, then you need a certified GPS navigator (e.g., GNS430/530, GTN650/750, etc.).
 
Can someone tell me if a certified GPS is required to be IFR legal in an experimental aircraft? Or just a WASS GPS installed?
thanks

The complex (e.g., FAA) answer. To be used for ifr other than just 'awareness' a GPS must be 'approved'. What this means is defined in FAR 1.1 (definitions). There are a lot of words but basically it must meet the performance specifications of the applicable TSO. These are so onerous that the only practical solution is to use a GPS which has a TSO. This is what people usually mean by 'certified'. BTW, you can buy used TSO 129 GPS units that are not WAAS enabled. For IFR you need to abide by the TSO 129 restrictions.
 
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