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IFR requirements

H

HBpilot

Active Member
I have read pages and pages on the internet and on this board, but really I need some input from other builders.
While I am still far away from installing avionics, I am trying to plan the strategy mostly for financial planning purpose. I know that avionics change every year, but I am trying to understand the necessary requirements for what I am trying to accomplish.

My goal is to build an airplane that will mostly fly VFR, but occasionally IFR too. Let me clarify that, I am not a fan of flying single engine with less than 1000ft ceiling (not the debate here). My goal is to be able to file IFR and get to destination and fly an LNAV approach. I do not need an ILS or even a VOR receiver. It is my understanding that they will be decommissioned in the future anyway.

I read the IFR equipment requirement, and was wondering if my planned configuration would fit the purpose with the regulation.

I would install a simple Dynon D10 or similar (I read a whole thread on how it cannot display or display the CDI with the attitude indicator, but then again not the point here). Would that satisfy the Instrument requirement to be certified IFR ?

For the GPS, my understanding is that to just fly an LNAV approach it doesn't have to be a WAAS certified GPS. What else do I have to look for when buying a GPS, in order to be approved for what I want to do ? Any model recommendation as an example (ADS-B compatible) ?

Comm and xpdr. Do they have to be TSO to be IFR approved ?

I am planning to also get one of the system like iLevil for crosscountry flying, etc... It has a GPS (used as backup), ADS-B integrated, etc... I know there is an issue with ipad overheating, that is my main concern. Any bad experience with such system ?

Autopilot ??? Big mystery to me. I would like to be able to couple it to the flight plan and altitude hold. Any cheap suggestions ?

It seems to me that as far as redundancy, the D-10 has its own backup power and so does the iLevil. Only concern would be the pitot tube. Do people install 2 pitot tubes (heated, unheated).

I read so many contradictory comments about whether you can use TSO vs non TSO equipment in an experimental aircraft. How about for required equipment for IFR rating ?

Any good link that would answer these questions is welcomed.

Thanks for your help.
 
The great thing about VAF is there is a lot of information here. An even better thing is that sometimes that information is correct.

Basically, any approach-capable GPS will do an LNAV approach. Older units which were certified under TSO129 will require a VOR receiver in addition - this requirement is regulatory in nature and not technical i.e. the GPS doesn't depend or interface with the VOR receiver in order to accomplish the approach.

The information about the Dynon D10A not being able to display a CDI along with the attitude indicator is false. I have done dozens and dozens of approaches this way. The CDI is displayed along the bottom of the attitude indicator page for lateral guidance.

The autopilot built into the D10A works great - I've used it many times. It is basic compared to what is built into the more expensive EFIS systems but it is far more capable than what is typically found in the GA fleet. Heading, track, or GPS for lateral nav and altitude hold w/pre-select is built-in - just add the servos and wiring.

The comm and transponder don't really have an IFR approval, but the transponder does have to be capable of meeting the relevant TSO. I'm not aware of any sold today or within recent memory that don't meet this requirement.

I only installed one pitot tube (heated, w/aoa). I couldn't think of any realistic scenario where a second pitot system significantly reduced any risk, but it certainly increases cost, weight, and complexity.
 
Above post is correct.
Transponder has to meet TSO, even for VFR use.
For ifr use the gps must meet a TSO. Older, non WAAS units have TSO 129. King KLN 89B, Garmin 300, for example. They can only do non precision LNAV approaches, and you are supposed to have back up equipment, e.g., VOR. These are available used, new TSO 129 boxes are no longer sold. New boxes meet TSO 145/146 (I think) and are WAAS capable. They can usually do precision LPV approaches as well as LNAV. No back up is required. They are supposed to be installed as outlined in their installation manuals, with restrictions on antenna placement and viewing angles, etc. Do not confuse WAAS and TSO. Lots of WAAS gps boxes are available, but few are TSO'd. The least expensive TSO'd new ifr navigator is probably the Garmin 400W.
You asked about getting an ifr rating? The current PTS requires that you demonstrate three different types of approaches, one of them either an ILS or an LPV. So while you can take the test in an airplane with just a VOR/localizer/glide slope (ILS; then VOR, LOC, or SDF approaches) you cannot take the test in an airplane with just gps, that only gives you two types. Strictly speaking the same is true for an IPC.
 
About ADSB out: none of the TSO 129 boxes can be used after 2020.
All of the TSO 145 boxes meet the FAR 91.227 requirements, but watch out! they use different data transmission formats; you must make sure your transmitter (mode SES transponder or UAT) can read your box. Or there are stand alone gps boxes for ADSB only (same communication issue).
 
Are there any GPS receiver/antenna that are WAAS and TSO 145/146 compliant, that could be used with an ipad as interface for flight planning, and that could be coupled with the D-10 to use during approaches ?
Having 2 GPS receiver, would that count as a backup ?
Dont know what is more difficult, planning ahead and understanding it, or the actual wiring ? LOL (that's because I dont know about the latter one yet)
 
HBpilot said:
Are there any GPS receiver/antenna that are WAAS and TSO 145/146 compliant, that could be used with an ipad as interface for flight planning, and that could be coupled with the D-10 to use during approaches ?
Having 2 GPS receiver, would that count as a backup ?
Dont know what is more difficult, planning ahead and understanding it, or the actual wiring ? LOL (that's because I dont know about the latter one yet)
Click to expand...

Sort of, but not necessarily with the equipment mix you mentioned.

Garmin has a wifi input from the Garmin Pilot application to their GTN6xx/7xx

Dynon/AFS just announced wifi input from Foreflight, but the interface is to AFS 5xxx or Dynon Skyview.

This is an area in which technology is constantly evolving. I would expect to see new products/features announced quarterly.

If I understand your backup question I think you are referring to the old TSO 129 requirement for a backup device. No, another GPS doesn't count. They are looking for a VOR, NDB, etc.
 
HBpilot said:
what are the cheapest options for autopilots ? nav coupling and alt hold.
Click to expand...

This is another area in which technology has changed over the last couple of years. In years past, you purchase an autopilot head that had a certain list of features/functions. Some had more and some had less.

Many of the EFIS vendors now have EFIS that can control autopilot servos directly with out requiring an external autopilot head device. This has the benefit of providing more features/functions at a lower price. The only downside is related to risk management and redundancy which I won't elaborate on here. That quickly becomes a religious debate with no universally correct answer.

But don't expect that EFIS that's been on the market for awhile to support AP servos. Talk with your avionics vendor to determine your options and cost.
 
An example of one I installed recently in a Lanceair is:

Dynon:
Skyview Touch
ARINC-429
Engine monitor
COM
I-Com
261 Transponder
Autopilot servos
Dual AD-ADHRS

Plus:
Garmin 430W (TSO'd) which feeds legal position data to the Dynon 261 XPNDR (required for 2020 legal ADS-B) and NAV antenna for VOR (Garmin only).

Without the 430W, it would not be legal for IFR today. Hopefully the FAA follows their ADS-B logic allowing equipment that meets TSO requirements to be used in experimental AC.

EDIT: corrected
 
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HBpilot said:
what are the cheapest options for autopilots ? nav coupling and alt hold.
Click to expand...

If you already have a Dynon D10A, the autopilot servos will add about $1500 and give you those capabilities plus a couple other minor additions. If you go standalone (TruTrak etc.) expect to pay a bit more.

Opinion:
The autopilot (and similar magic) is a nice tool to have, but too many pilots depend on it too heavily and are only marginally capable of flying in IMC by hand. This lack of ability has brought down airplanes far larger than an RV in cases where the magic stopped working and is something to consider while doing your IFR work.
 
HBpilot said:
How about for required equipment for IFR rating ?
Click to expand...

As said before, you can't get your IFR rating with just a GPS, you still need something else. I use a VAL Ins-429 all in one unit that provides VOR/LOC/GS and MB in one unit. With this in your aircraft you can get your instrument rating.

:cool:
 
First of all, thank you all for your valuable input. This is great info.

What I dont understand, FAR 91.205 does not refer to a backup system.

"(2) Two-way radio communication and navigation equipment suitable for the route to be flown."
That's a rather vague description.

If I have 1 GPS to fly enroute and fly an LNAV approach, that seems suitable to me ? Reasonable ? No.
Is there another regulation i am missing ?
 
GalinHdz said:
As said before, you can't get your IFR rating with just a GPS, you still need something else. I use a VAL Ins-429 all in one unit that provides VOR/LOC/GS and MB in one unit. With this in your aircraft you can get your instrument rating.

:cool:
Click to expand...

Sorry I did not mean IFR rating, I meant IFR requirements.
I already have my IFR rating and thousands of hours flying commercial.
 
HBpilot said:
First of all, thank you all for your valuable input. This is great info.

What I dont understand, FAR 91.205 does not refer to a backup system.

"(2) Two-way radio communication and navigation equipment suitable for the route to be flown."
That's a rather vague description.
Click to expand...

"suitable for the route to be flown" Also means the navigation equipment has to be approved for IFR.
 
HBpilot said:
First of all, thank you all for your valuable input. This is great info.

What I dont understand, FAR 91.205 does not refer to a backup system.

"(2) Two-way radio communication and navigation equipment suitable for the route to be flown."
That's a rather vague description.

If I have 1 GPS to fly enroute and fly an LNAV approach, that seems suitable to me ? Reasonable ? No.
Is there another regulation i am missing ?
Click to expand...

So if you have a non-WAAS box what if you have a RAIM failure enroute or at your destination?
 
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GalinHdz said:
Actually a great point but irrelevant to what he is trying to do. This is the answer:


Anything else depends on your level of risk tolerance.

:cool:
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It is if all he's got is a non-WAAS GPS and no NAV radio which is what I understood he was proposing based upon the original post .
 
Auburntsts said:
It is if all he's got is a non-WAAS GPS and no NAV radio which is what I understood he was proposing based upon the original post .
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This is indeed what I was asking, but I also know that I wouldn't necessarily be comfortable with it.
I wanted to understand the minimum to get away with, and then add on what I think makes sense.

"route to be flown" does not include the approach, which would have different requirements, is this what you mean ? Makes sense.
 
HBpilot said:
This is indeed what I was asking, but I also know that I wouldn't necessarily be comfortable with it.
I wanted to understand the minimum to get away with, and then add on what I think makes sense.

"route to be flown" does not include the approach, which would have different requirements, is this what you mean ? Makes sense.
Click to expand...

Actually, my understanding of 91.205 is that it does include the approach. In any event I'm just not risk tolerant enough to not have more than one navigation system for IMC ops. YMMV....
 
There's one other issue. With a non-WAAS box you'll need a second non-GPS nav system in order to legally file an alternate if the WX is worse at destination than the 1-2-3 rule.
 
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Auburntsts said:
There's one other issue. With a non-WAAS box you'll need a second non-GPS nav system in order to legally file an alternate if the WX is worse at destination than the 1-2-3 rile.
Click to expand...

See. I can't find anything that says you have to have a backup system.
Here's a link to an EAA chapter article. Seems a little outdated, but near the bottom it does say "it's important to note is that the minimum equipment called out by 91.205 does not include any kind of system backup or redundancy"
Again, only looking at the legal aspect to be certified IFR, and add on items to meet my comfort level.

If I plan to get to my destination where I have a 2000ft ceiling in the forecast, I can do a LNAV approach OR a visual approach, and also plan an alternate.
I would be more comfortable in my opinion than flying single engine on an ILS to 200ft ceiling, knowing I have a WAAS GPS as a backup. That's comfort, not regulation.
My plan is to file IFR for enroute flying and land at an airport that has good/marginal weather. That's what I am trying to find out. What do I need to do this legally ?
 
Legally, as long as the destination meets the 1-2-3 rule and you don't lose RAIM (non-WAAS ) no back-up is required. Your decision as to whether thsy's a prudent strategy. IMO you're asking for trouble-- better off just staying VFR. That's just my 2 cents ......
 
As poster #2 said, there's lots of info here, and sometimes it is right. Sometimes not! For instance, one poster has confused ADSB and IFR. There is no requirement to have a gps feeding your transponder for IFR. That's for ADSB.
"suitable" navigation equipment: With respect to RNAV(GPS), "suitable" is DEFINED in FAR 1 (definitions)! But nothing else. There is NO requirement for part 91 aircraft to use TSO'd VORs or DMEs. Just for ifr gps, transponders, and, starting in2020, ADSB-out. And in all cases, the equipment does not have to carry a manufacturer's TSO, if the owner/operator can somehow show that it meets the TSO requirements.
Backups: For type certified aircraft these requirements are buried in the type certification paperwork. For Experimental aircraft, it's up to the builder unless his operating limits say otherwise, and usually they do not. Except for TSO 129 gps, where FAR 1 gives the FAA the power to make up the rules and publish them in the AIM.
TSO 129 gps backups: another 129 GPS is not good enough. If you have a TSO 145 gps it doesn't require a backup.
A D-10 can display CDI info from modern Ifr GPS receivers, you need an ARINC coupler. Not sure about older gps boxes.
The bottom line here is that there is no inexpensive way to equip for GPS-ifr. And in most people's opinions, even if not required, back up nav AND flight instruments make a lot of sense, even where they're not required.
 
Auburntsts said:
Legally, as long as the destination meets the 1-2-3 rule and you don't lose RAIM (non-WAAS ) no back-up is required. Your decision as to whether thsy's a prudent strategy. IMO you're asking for trouble-- better off just staying VFR. That's just my 2 cents ......
Click to expand...

See what I mean about bad info? The above statement is simply incorrect. TSO 129 gps boxes may not be used for ifr without backup equipment on board. You do not have to use it if the gps is working, but it has to be there!!! And then there is the additional requirement that if an alternate is required, either the primary or the alternate (this is a recent change) must be doable without the 129 gps.
 
I stand corrected about the legality of not having a backup for a TSO C129/C196 box. Everything else I posted regarding an alternate or RAIM is correct however.

It's with a C145/C146 WAAS box that no backup is required for IFR ops nor is a backup required for an alternate.
 
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Once again, thank you all for your input.
It doesn't matter if some were inaccurate. Afterall it's a forum for discussion.
My conclusion, I am still not sure I understand everything about it, but I have learnt a lot from you.
What I know now, the investment to have a certified airplane seems too important for just the comfort of filing IFR. And I am just talking about my own situation.
 
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Been going through the same questions

I've settled on this approach - until the money tree gets a bit bigger....

I've got a Dynon D-100 to which I'm adding a GX60 gps/comm (non-waas) and a VAL Nav2000 nav radio.

Those should drive the HSI display in the D-100 and if it fails I can do a LOC approach using the internal CDI of the VAL.
 
HBpilot said:
Once again, thank you all for your input.
It doesn't matter if some were inaccurate. Afterall it's a forum for discussion.
My conclusion, I am still not sure I understand everything about it, but I have learnt a lot from you.
What I know now, the investment to have a certified airplane seems too important for just the comfort of filing IFR. And I am just talking about my own situation.
Click to expand...



Don't forget about IFR currency requirements. You need 3 types of approaches in real or sim conditions every 6 months. I don't think you can accomplish that, in your aircraft, with just GPS.
 
Indytim said:
Don't forget about IFR currency requirements. You need 3 types of approaches in real or sim conditions every 6 months. I don't think you can accomplish that, in your aircraft, with just GPS.
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Uh...I just checked FAR 91.57 again (to make sure it hasn't changed). No requirement for three different types of approaches that I can find. Just six approaches, holds, and intercepts.
 
Indytim said:
Don't forget about IFR currency requirements. You need 3 types of approaches in real or sim conditions every 6 months. I don't think you can accomplish that, in your aircraft, with just GPS.
Click to expand...

Three types of approaches? Hrm... Are you thinking of an Instrument Proficiency Check? If I recall correctly, all that's needed for currency is to log in the previous 6 months the following items: at least 1 hold, at least 1 intercept, and at least 6 instrument approaches (type not specified). If you're beyond 6 months, you've got another 6 months to get back current on your own by flying and logging the above items. If you go beyond 12 months, then you need to get an IPC done, which would require the 3 different types of approaches and the appropriate navigation instrumentation to do those.
 
Krynn said:
Three types of approaches? Hrm... Are you thinking of an Instrument Proficiency Check? If I recall correctly, all that's needed for currency is to log in the previous 6 months the following items: at least 1 hold, at least 1 intercept, and at least 6 instrument approaches (type not specified). If you're beyond 6 months, you've got another 6 months to get back current on your own by flying and logging the above items. If you go beyond 12 months, then you need to get an IPC done, which would require the 3 different types of approaches and the appropriate navigation instrumentation to do those.
Click to expand...

You're right, I was wrong. I was thinking of the IPC.

61.57 Recent flight experience: Pilot in command.
c) Instrument experience. Except as provided in paragraph (e) of this section, no person may act as pilot in command under IFR or in weather conditions less than the minimums prescribed for VFR, unless within the preceding 6 calendar months, that person has:
For the purpose of obtaining instrument experience in an aircraft (other than a glider), performed and logged under actual or simulated instrument conditions, either in flight in the appropriate category of aircraft for the instrument privileges sought or in a flight simulator or flight training device that is representative of the aircraft category for the instrument privileges sought --
At least six instrument approaches;
Holding procedures; and
Intercepting and tracking courses through the use of navigation systems.
 
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I recently had a condition inspection performed on my RV-7 by an A&P, IA. I asked him to do a pitot static check and a transponder check so it would be legal for IFR, *just in case*.

He took the airplane to an avionics shop since he was not equipped to do the checks. The mechanic at the avionics shop would not do the pitot static check because he said the plane was not properly equipped for IFR. This guy claimed that a standalone attitude indicator was required.

The panel in the plane is a Stein Air panel with Dual Garmin G3x displays, a GTN650 and a second Com radio, along with a Garmin 330 ES xpdr... Either one of the G3X displays is capable of providing attitude info, slip skid, compass heading and rate of turn independently should the other one fail. Also a backup battery capable of providing 90 minutes of back up power to the entire system.

He cited some obscure (to me) FAR which seemed to apply to TC airplanes equipped with certified Garmin panels... Not having chapter and verse to cite, I did not argue except to say that I did not agree.... Needless to say I will not use this guy again, but WHAT ARE THE RELEVANT FAR'S that I need to cite?
 
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find a different shop. there is no requirement for a standalone indicator in a glass cockpit experimental. he is mistaken. I do believe there is such a thing in the STC to install the garmins in a TC aircraft, that is where he is probably getting that from. He could also be looking at 23.1311 which requires backup in a certified system, but we all know that section 23 does not apply to EAB only FAR91.205 needs to be satisfied.

bob burns
RV-4 N82RB
 
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IFR TSO Equipment for Experimental

I keep reading that in order to be legal IFR we need to use TSOed GPS. Really? Nothing else in the experimental aircraft requiresTSOed equipment for IFR. (Transponder is for VFR). This EAA articles (link below) says as the builder we can certify our equipment meets TSO requirements but that is not the same thing as equipment that has been manufactured as TSOed.

https://www.eaa.org/en/eaa/aviation...ions/equipping-a-homebuilt-for-ifr-operations

Am I reading this correctly? Seems like the EFIS manufacturers Dynon, Grand Rapids, G3X etc, could help us self certify that our equipment can meet TSO requirements and then we can certify our home builts as IFR legal airplanes.

Right?
 
That is basically correct. The FARs in part 91 say "suitable" navigation equipment. You then have to turn to FAR 1.1 (definitions) which says nothing about VOR or ILS or ADF etc but does define "suitable Rnav including gps". Basically it says suitable is whatever the FAA says it is in their non regulatory publications like AIM and advisory circulars. This makes these usually non regulatory publications regulatory, for ifr gps! The legal phrase is "regulatory by reference". There are other examples in the FARs.
Can we self certify? The answer is yes, you can state the box meets the TSO requirement even if the manufacturer does not. In principle. But in practice TSO145/146 is so complicated that no mere mortal could answer 'yes, it meets the TSO requirements' honestly. I heard that Garmin, King, etc., spent tens of million dollars on engineering time demonstrating compliance. Even then, they had to get a waiver/AMOC on a bunch of stuff. Look in the front of a Garmin gps installation manual for details. The TSOs are incredibly complex. I know GRT attempted to certify a lower cost ifr gps; as far as I can tell that project proved too complex, and is on the back burner now.
BTW, transponders and, starting in 2020, ADSB-out boxes, must also 'meet the requirements' of a TSO. At least one manufacturer is testing the waters with an ADSB-out box that they claim 'meets the requirements' but does not actually have a TSO. So far, the FAA seems okay with it, as far as I can tell.
 
sglynn said:
I keep reading that in order to be legal IFR we need to use TSOed GPS. Really? Nothing else in the experimental aircraft requiresTSOed equipment for IFR. (Transponder is for VFR). This EAA articles (link below) says as the builder we can certify our equipment meets TSO requirements but that is not the same thing as equipment that has been manufactured as TSOed.

https://www.eaa.org/en/eaa/aviation...ions/equipping-a-homebuilt-for-ifr-operations

Am I reading this correctly? Seems like the EFIS manufacturers Dynon, Grand Rapids, G3X etc, could help us self certify that our equipment can meet TSO requirements and then we can certify our home builts as IFR legal airplanes.

Right?
Click to expand...

Good luck with this. The GPS navigator needs to meet certain TSOs, and that means the electronics, the databases AND the software. I think it's academic whether it "meets the TSO" or "is TSO'd", since no homebuilder out there is going to test his equipment (antenna, cabling, electronics, displays, software, etc.) to a TSO C146 (and others) level.
 
edneff said:
He took the airplane to an avionics shop since he was not equipped to do the checks. The mechanic at the avionics shop would not do the pitot static check because he said the plane was not properly equipped for IFR. This guy claimed that a standalone attitude indicator was required.
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Interesting, doing an "IFR Cert" on the altimeter, encoder, static system and transponder per 91.411/91.413 has nothing to do with the aircraft being actually equipped for IFR. The "Operator" is responsible to ensure the aircraft is equipped as required for the flight. As a repair station I have no right, or obligation, to determine if the aircraft can actually be operated under IFR conditions.

As a repair station I don't ever certify any aircraft for IFR, I certify only that it passed the tests as required by 91.411, 91.413
 
sglynn said:
.......Am I reading this correctly? Seems like the EFIS manufacturers Dynon, Grand Rapids, G3X etc, could help us self certify that our equipment can meet TSO requirements and then we can certify our home builts as IFR legal airplanes.

Right?
Click to expand...

Not to be facetious here, but do you really want to be bombing along at 180+kts seeing traffic reports based on a GPS to and from other aircraft that have been "self certified" to be "almost as good because I think so" to keep you separated, or flying down through the clouds with something that might be "close" to accurate and the only way you really know is that you self certified that it is? This goes way beyond just hoping something is good enough and it is incredibly more complicated than simply being "almost just as good because I said so, or someone makes a statement on a website".....

To the other point, if your shop won't do a pitot static check because they think they need to worry about IFR "certification", then they are just either completely mis-informed, or incompetent. As Walt stated, that is not their job as part of that check - only to verify that the equipment as installed meets said aformentioned requirements of the test. Certified or not, a "shop" is not legally able to make your aircraft qualified from a legal standpoint....they can simply state that the installed equipment either passes/meets the published test requirements...or not.

I get calls from owners and other shops regularly and have to explain this to them. I've said it many times before and I'll say it again. CALL the shop you intend to use before you go there and verify they have a clue about experimental avionics and aircraft along with real world experience. If they don't, go to someplace that does.

Just my 2 cents as usual.

Cheers,
Stein
 
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