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What is a Modern IFR Airplane?

comfortcat

comfortcat

Well Known Member
Greetings!

OK, I'm now starting to work on the panel of my RV-9A and start planning instrumentation.

So here is the question:

I'm planning on an IFR panel with GPS ONLY! No VOR, GS, MRKR, ADF, etc.

My worldwide corporate pilot friend has not used a VOR in 10 years.

I'm a digital guy (Systems analyst) and I do have an autopilot (Single pilot jets require an autopilot)


Thoughts?

Dkb
 
That's just what I did. Three screen G3X, Dynon D10A, and two MGL V-6 comms. I really didn't see the need for all of the other nav equipment. At some point I'll add a certified GPS to truly make it IFR legal....when I become IFR legal. I'm hoping that I won't be forced to install a nav radio, because I really don't think I'll ever use it.
 
You only have to have the equipment for the approach you intend to shoot. Keep in mind, an ILS has 200' mins. Not all airports have LPV GPS approaches. Although, it would not surprise me to see ILS approaches start to vanish. At our local airport, we have an ILS with a VOR transition if you take the full approach. but then again, we also have a LPV approach for the same runway.
 
comfortcat said:
Greetings!

My worldwide corporate pilot friend has not used a VOR in 10 years.
Click to expand...

That maybe true, but ask him when's the last time he shot an ILS--still need a VOR receiver for that. I opted for a 2 screen G3X, SL-30, GTN650, and a GX autopilot. Concur with no MB or ADF--neither is needed for IFR operations here in the US.
 
I agree with Todd. Your friend may not have used a VOR for enroute nav in the past ten years, but I will bet he has been vectored to quite a few ILS approaches during that time. Having said that, I have been flying my RV-10 all over the country in the past four years and almost always file IFR on cross country flights, regardless of the weather. I have flown very few "actual, no BS" instrument approaches and the only "for real" ILS I can recall was in Canada a couple of years ago. I am pretty conservative about what kind of weather I will go in, but I guess my point is that I still want to have ILS capability, but recognize that I will rarely need it. But, when I need it..............
 
Most of the time a certified waas gps is all you need. But once in a while...
My last ifr student's x/c we planned a gps-LPV approach into KCIC. But its minimums were 300 agl! Not good enough!! Wx was exactly at 200 and 1/2, and the ILS got us in when nothing else would.

Also, although you would be fully ifr legal, you could not take your ifr check ride in the plane. Instrument proficiency checks are also problematical although I have a work-around.

PS to D.M.: in '69 I was 21, too. One of my favorite songs
 
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satellites fail and also have outages (check NOTAMS)

a solar flare can also cause severe GPS anomalies

also you can simply be flying and lose your gps integrity....what's your plan B? knew of one 430W that would start saying "SERVICE UNIT" during flight
 
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I am not sure where exactly your friend has been flying. I fly a good part of the world and often shoot VOR approaches. In fact JFK probably does more VOR/DME approaches to 22L then any other approach at the airfield.

Having said that however I see no need for that in a RV for the type of instrument work I am willing to do. ILS will be around for a long time to come and it would be nice to have one but there is certainly no need. I would not be planning a flight based on ILS minimums in a RV. If a GPS approach would not get me in then I would use a different routing or wait for better weather.
I don't completely understand the rules on experimental aircraft when it comes to what a legal GPS for IFR approach operations actually is. The standard seems to be a garmin 430W in which case you get the ILS/VOR included. If your driving a EFIS with a non TSO'd gps the question becomes is that actually legal. Several RV pilots have told me that since the aircraft is experimental you could as a example shoot a GPS approach off a 496/696/796. A long forum search however has convinced me that is not legal based on many opinions here that I value. I don't believe its even legal for airways nav.

The question then becomes do you need a 430/530 ect which normally comes with the VOR/ILS or can you drive a EFIS with basically any GPS and be legal. I don't know the answer. Is there a TSO'd GPS to drive these units other then the Garmin 300 series without the above capabilities?

George
 
GPS/Nav/Comm and a Nav/Comm
If the 430 crapps out, you still have the Nav/Comm. It's also a lot cheaper than two 430s.

If you want to go anywhere in northern Canada, I'd want one or maybe two ADFs.
 
I didn't see the need for two VORs so I've got an SL30 and a Garmin 420w (no vor). This also avoids having all my eggs in one basket.
 
Just a GPS...

I flew behind a King KLN-89B in my Skyhawk, and I like King equipment.

So, I'm thinking a Dynon Skyview (which has a GPS for backup) and a KLN-94 for the IFR approach GPS.

So, I'll have:

1- Skyview EFIS w/ Autopilot
2 - Dynon comms (I assume they will be ready when I am)
1 - KLN-94
1 - Dynon Transponder

I will have a second display for backing up the Skyview, but I'm thinking something in the Android family. 7" permanently installed and external GPS antenna in the panel and that will backup EVERYTHING except comm.

No ILS, ADF, VOR

Hmmmm....
sailvi767 said:
The question then becomes do you need a 430/530 ect which normally comes with the VOR/ILS or can you drive a EFIS with basically any GPS and be legal. I don't know the answer. Is there a TSO'd GPS to drive these units other then the Garmin 300 series without the above capabilities?

George
Click to expand...
 
Is it legal?

I asked a friend of a friend who works in the FAA's legal office. He said:
1. FAR's restrict E-AB to vfr "unless authorized by the administrator"
2. Most operating limitations contain that authorization, if FAR 91.205 is followed.
3. FAR 91.205 requires one to have "suitable" navigation equipment.
--Now, here is the key --
4. To my surprise, "suitable", at least with regard to GPS or any RNAV equipment, is defined in FAR 1.1
5. FAR 1.1 says suitable equipment is described in various FAA guidance material. The FAA interprets this as meaning you must follow the TSOs, a/c, and AIM, which normally are not regulatory but now are by virtue of FAR 1.1. It is not required that the radio be TSO'd, but if it is not then the owner must be able to show that it meets the standards in the TSO. Of course, that is beyond the capability of most owners.
 
BobTurner said:
I asked a friend of a friend who works in the FAA's legal office. He said:
1. FAR's restrict E-AB to vfr "unless authorized by the administrator"
2. Most operating limitations contain that authorization, if FAR 91.205 is followed.
3. FAR 91.205 requires one to have "suitable" navigation equipment.
--Now, here is the key --
4. To my surprise, "suitable", at least with regard to GPS or any RNAV equipment, is defined in FAR 1.1
5. FAR 1.1 says suitable equipment is described in various FAA guidance material. The FAA interprets this as meaning you must follow the TSOs, a/c, and AIM, which normally are not regulatory but now are by virtue of FAR 1.1. It is not required that the radio be TSO'd, but if it is not then the owner must be able to show that it meets the standards in the TSO. Of course, that is beyond the capability of most owners.
Click to expand...


Fortunately, this is somethign that the EAA has worked with the FAA on for us:

http://members.eaa.org/home/homebuilders/faq/Equipping a Homebuilt for IFR operations.html
 
Mark33 said:
Very interesting article. So according to this EAA document, a person could file and fly IFR with equipment such as a G3X....even though it's not TSO'd....unless I'm missing something here.
Click to expand...

Reading the EAA link, I see no real way to be legal unless you have TSOd equipment. From the G3X website

"It will even fly a preset vertical navigation (VNAV) profile down to minimums when combined with GTN or GNS series avionics. "

Source: https://buy.garmin.com/shop/shop.do?pID=63892

Under the "Highly Evolved ? Not Highly Expensive" paragraph.
 
Ron Lee said:
Reading the EAA link, I see no real way to be legal unless you have TSOd equipment. From the G3X website

"It will even fly a preset vertical navigation (VNAV) profile down to minimums when combined with GTN or GNS series avionics. "

Source: https://buy.garmin.com/shop/shop.do?pID=63892

Under the "Highly Evolved ? Not Highly Expensive" paragraph.
Click to expand...


The followig is a quote from that EAA link:

"The bottom line;
All of this leads us to the conclusion that none of the equipment installed in a homebuilt aircraft is required to be built under a TSO authorization. But in most cases, it?s to the builder?s advantage to install ?TSO?ed? equipment if possible."

So I guess I'm still missing something??:confused:
 
Under "What about GPS?"

"However, if the equipment is not built under a TSO authorization, it is up to the owner/operator to verify and document that the equipment performs within the required specifications. It is also the owner or operator's responsibility to document the necessary flight-test data showing that the installation performs within the required accuracy parameters. (Bolding added)"
 
Ron Lee said:
Under "What about GPS?"

"However, if the equipment is not built under a TSO authorization, it is up to the owner/operator to verify and document that the equipment performs within the required specifications. It is also the owner or operator's responsibility to document the necessary flight-test data showing that the installation performs within the required accuracy parameters. (Bolding added)"
Click to expand...

Yeah, I saw that part as well. I just wish the article would have been a little bit clearer and not put that little part in there at the end and tease us into thinking that you could use non TSO's equipment. In addition, here is another quote from that article"

"Thus, the answer is NO, the instruments and equipment installed in your homebuilt under the requirements of 91.205 are not required to be ?TSO?ed?."
 
The correct statement is that the gps must meet the TSO standards. This can be accomplished by relying on the manufacturer's certification ("TSO'd"), or by the owner certifying that the equipment meets the standards. However, given the complexities of the TSO, self-certifying is practically impossible.

As a side note for those contemplating GPS only ifr panels; the GPS must meet the newer c145 or 146 standards. Older non waas units certified to c129 do not qualify.
 
don't take this the wrong way, but you guys baffle me if you, yourself, are okay with flying in IMC with non certified avionics/equipment?

The plane is one thing, the engine another, but the AVIONICS?!
 
bkthomps said:
don't take this the wrong way, but you guys baffle me if you, yourself, are okay with flying in IMC with non certified avionics/equipment?

The plane is one thing, the engine another, but the AVIONICS?!
Click to expand...

Point well taken. However, even though the avionics are not TSO'd, .... how does that really make that particular part of the aircraft any different than any other part of it (regarding safety)? If there are any differences in the sophistication or accuracy in the TSO'd equipment VS the non TSO'd equipment (and maybe there are real differences that I'm not aware of) then it would be a valid argument as to safety. If in reality it's just a sticker that's stuck on the side of it that says "TSO'd", and lot of expensive legal mumbo jumbo, and nothing that's truly a safety issue, than I personally wouldn't feel any more at risk flying without TSO'd equipment as I would with it.....just as with the rest of the aircraft. I think one component of the aircraft is just as important any other part with regards to safety. There was another thread with a similar topic and one of the avionics experts stated that in reality the non TSO'd navigational equipment was probably even more accurate that the TSO's equipment due to the non TSO'd equipment being several generations newer than the TSO's equipment. So, once again, I'm certainly no expert on this subject by any stretch of the imagination, but I just find it interesting to see where fact or fiction stands regarding true safety issues VS legality and government red tape. Rest assured that when I finally do get my instrument ticket that I'll be flying both safely and legally. :)
 
Mark33 said:
Point well taken. However, even though the avionics are not TSO'd, .... how does that really make that particular part of the aircraft any different than any other part of it (regarding safety)? If there are any differences in the sophistication or accuracy in the TSO'd equipment VS the non TSO'd equipment (and maybe there are real differences that I'm not aware of) then it would be a valid argument as to safety. If in reality it's just a sticker that's stuck on the side of it that says "TSO'd", and lot of expensive legal mumbo jumbo, and nothing that's truly a safety issue, than I personally wouldn't feel any more at risk flying without TSO'd equipment as I would with it.....just as with the rest of the aircraft. I think one component of the aircraft is just as important any other part with regards to safety. There was another thread with a similar topic and one of the avionics experts stated that in reality the non TSO'd navigational equipment was probably even more accurate that the TSO's equipment due to the non TSO'd equipment being several generations newer than the TSO's equipment. So, once again, I'm certainly no expert on this subject by any stretch of the imagination, but I just find it interesting to see where fact or fiction stands regarding true safety issues VS legality and government red tape. Rest assured that when I finally do get my instrument ticket that I'll be flying both safely and legally. :)
Click to expand...
+1
Once one moves into the EXPERIMENTAL world from the strictly factory built GA world one must question exactly what safety advantage having a government approved sticker on a piece of equipment truly does contribute to the SAFETY of flight when using that piece of equipment. Flying in a certificated GA airplane we tend to unquestioningly believe authority figures when they communicate to us that this such-n-such piece of equipment has been deemed safe(r) than that such-n-such piece of equipment because of a document with the appropriate governmental "stamp of approval". The truth concerning the capabilities of those two pieces of equipment may be very different than our perception.
 
Brantel said:
Where you guys going to buy all this non TSO'd gear that meets the TSO requirements?
Click to expand...

LOL.... or maybe better "crying out loud"!! :( That really is the sad part... we really are stuck with having to abide by with what the government says we can or can't do.....for now anyway. But that's another example of the beauty of this experimental class; as time goes by, and technology improves, and we can demonstrate that one piece of equipment is just as good without a government sticker as one is with it, then maybe, just maybe, the people that make the rules will start to open their eyes. One little example of this is that now we're able to use our iPads for maps instead of paper sectionals. And another example is the lobbying that's taking place to let people that would otherwise have to quit flying due to "maybe" not being able to pass their 3rd class medical continue to fly their airplanes under light sport rules. So, I guess all we can do is to continue to demonstrate that whatever we do in this experimental category is just as safe anything that can come out of a factory....and that includes using non TSO'd equipment. I think as long as we have companies such as Garmin (just to mention one) that are providing us with equipment that's at the level of sophisticated that's available to now, I feel confident that our navigational safety is in good hands and that over time "that sticker" on the side of that particular piece of equipment really won't mean anything.
 
Good question.

Brantel said:
Where you guys going to buy all this non TSO'd gear that meets the TSO requirements?
Click to expand...

My Garmin 430W comes to mind. This unit has a built in self-analysis system to tell if it is indeed accurate during approaches. The unit is equipped with a system named RAIM, for Receiver autonomous integrity monitoring, which continually self-tests and will warn you of any discrepancies. Approaches down to minimums need to have a definite accurate indication...obviously.

I don't know of another system without a TSO that does this.

Best,
 
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Mark33 said:
Point well taken. However, even though the avionics are not TSO'd, .... how does that really make that particular part of the aircraft any different than any other part of it (regarding safety)? If there are any differences in the sophistication or accuracy in the TSO'd equipment VS the non TSO'd equipment (and maybe there are real differences that I'm not aware of) then it would be a valid argument as to safety. If in reality it's just a sticker that's stuck on the side of it that says "TSO'd", and lot of expensive legal mumbo jumbo, and nothing that's truly a safety issue, than I personally wouldn't feel any more at risk flying without TSO'd equipment as I would with it.....just as with the rest of the aircraft. I think one component of the aircraft is just as important any other part with regards to safety. There was another thread with a similar topic and one of the avionics experts stated that in reality the non TSO'd navigational equipment was probably even more accurate that the TSO's equipment due to the non TSO'd equipment being several generations newer than the TSO's equipment. So, once again, I'm certainly no expert on this subject by any stretch of the imagination, but I just find it interesting to see where fact or fiction stands regarding true safety issues VS legality and government red tape. Rest assured that when I finally do get my instrument ticket that I'll be flying both safely and legally. :)
Click to expand...

There are many, many more aspects to a TSO than just accuracy. From a software standpoint alone, compliance with a TSO will (in the case of TSO C146) require compliance with DO-178B, which has all sorts of process requirements to ensure, as much as possible, robust, resilient software. It's not just about the accuracy of the equipment.
 
pierre smith said:
My Garmin 430W comes to mind. This unit has a built in self-analysis system to tell if it is indeed accurate during approaches. The unit is equipped with a system named RAIM, for Random autonomous integrity monitoring, which continually self-tests and will warn you of any discrepancies. Approaches down to minimums need to have a definite accurate indication...obviously.

I don't know of another system without a TSO that does this.

Best,
Click to expand...


Flying Scotsman said:
There are many, many more aspects to a TSO than just accuracy. From a software standpoint alone, compliance with a TSO will (in the case of TSO C146) require compliance with DO-178B, which has all sorts of process requirements to ensure, as much as possible, robust, resilient software. It's not just about the accuracy of the equipment.
Click to expand...

Very valid and well taken points...it's great learning new things!:)
 
Grand Rapids Technology lists an external RAIM GPS option for their EFIS systems on their pricing wizard at $750 with no mention of TSO or not.
 
pjaffray said:
Grand Rapids Technology lists an external RAIM GPS option for their EFIS systems on their pricing wizard at $750 with no mention of TSO or not.
Click to expand...

Ron Lee said:
Does it have GPS approaches like a Garmin 430(W)?
Click to expand...

It does not have a TSO and no it does not meet the standards for approaches like the 430(W).

There is way more to meeting the standards for an enroute and or approach certified GPS than just having RAIM or being WAAS capable. The documents that detail all of that are hundreds of pages deep.

There is no free or reduced lunch on this subject. Not sure you would really want it even if it was available. IFR approaches are serious business and you don't want to be fooling around with questionable NAV sources.
 
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The GRT $750 GPS is not approved for IFR, according to the GRT Horizon operating manual. GRT is advertising a TSO'd GPS receiver, available 2013. No details that I have seen, except price around $3K - 4K depending on if it has LPV approach approval or not.

As the article posted by Paul pointed out, part 91 only requires a few things to be TSO'd, such as ifr gps and transponders. There are hundreds of certified aircraft out there running around with a non-TSO'd King DME. I don't think they're particularly unsafe.
 
Ok so we have some old King DME's out there that are not TSO'd that one might say they can use for where DME is required in an experimental aircraft......boy that is really useful. :cool:

So what else is out there? "Insert Cricket noises here"

The point is there is no reason to get all wadded up again in a big thread that TSO's are not required for experimentals. What difference does it make if you can't buy non TSO'd gear that meets the TSO standards?
 
BobTurner said:
As a side note for those contemplating GPS only ifr panels; the GPS must meet the newer c145 or 146 standards. Older non waas units certified to c129 do not qualify.
Click to expand...

Pretty sure any unit previously certified under TSO c129 are grandfathered and legal. A manufacturer will not be able to design and certify a new GPS to c129.
 
Let us assume that a new RV will have a capable EFIS. They also want ILS and GPS approaches (minimum non-precision approach equivalent.....objective WAAS aided vertical guidance).

Since they have an EFIS with moving map, a Garmin 430W or equivalent is not mandatory.

What non-430W (or equivalent) options are on the market to get ILS and GPS approaches?

The Garmin SL30 provides ILS plus comm.
 
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Ken, I know we have had this discussion before. A c129 box certainly is still legal to use, but not as a sole source for ifr navigation. e.g. Not in a panel with only gps.
 
Ron, can you re-state your question? If you want non-precision gps the low cost path is to buy the used King KLN-90 that Stein is offering. If you want gps vertical guidance then the Garmin 4xxW is the lowest cost option that I know of. There was a time when UPS/Apollo provided competition, but those days are gone. GRT is promising to offer a less expensive option in 2013, but as far as I know it does not currently exist.
 
BobTurner said:
Ron, can you re-state your question? If you want non-precision gps the low cost path is to buy the used King KLN-90 that Stein is offering. If you want gps vertical guidance then the Garmin 4xxW is the lowest cost option that I know of. There was a time when UPS/Apollo provided competition, but those days are gone. GRT is promising to offer a less expensive option in 2013, but as far as I know it does not currently exist.
Click to expand...

Bob is right on here. The lowest cost practical box would be the 400w (if you have a G3X) at less than $4k, that is for a WAAS unit with both certified horizontal and vertical guidance and as a "navigator". That aside, older units from Garmin, King and UpsAT are affordable options.

Cheers,
Stein
 
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