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cccjbr6

Well Known Member
I have heard that to avoid the expense of adding a certified radio like a Garmin 430W to a panel with a G3X, some are mounting a Garmin handheld like an Aera with a WAAS engine to enable them to shoot GPS approaches. Is it legal in experimentals to shoot a GPS approach with such a setup in IMC?
 
cccjbr6 said:
I have heard that to avoid the expense of adding a certified radio like a Garmin 430W to a panel with a G3X, some are mounting a Garmin handheld like an Aera with a WAAS engine to enable them to shoot GPS approaches. Is it legal in experimentals to shoot a GPS approach with such a setup in IMC?
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Simply no.
 
in an emergency

I am studying for my IFR and in one of the standard FAA books, if I remember right, I think in the 2013 AIM, it did mention that GPS systems, like the Area series, with the signal integrity verification feature can be used in an emergency, even though it is still illegal to use for "normal" IFR.
 
In case of Mayday

Essentially, in a bona-fide Emergency, you can break any and as many FARS as you need to be able to safely conclude the flight.

You obviously need to be prepared to justify your actions, if requested by the administrator.
 
In response to those responses above that said in one word: no,.......
I have a much more elaborate response for you: No, no and more no.
 
Ask that person to show you a handheld waas GPS that has the GPS approach databases loaded in it.
 
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Dbro172 said:
Ask that person to show you a handheld waas GPS that has the GPS approach loaded in it.
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Depending on the GPS, it's possible. For example, I can manually plug in the fixes for the RNAV 34 approach at KSGS into Foreflight; it will happily show them and away I go. I even tried this with a safety pilot once and it worked sort of ok in clear weather. However...

It was murderous to use. Snatching a glance away from the panel to the iPad and back really broke up my scan. The accuracy of the lateral nav was extremely poor as compared to a CDI driven by a panel mount GPS. And no sequencing of the hold after going missed.

Would I do it in an emergency if both the panel mounted IFS GPS and nav receiver failed and there was no facility nearby that could do a ground-controlled approach? Sure. But at that point, there's not much to lose.

I'd never consider it under normal circumstances.
 
Don't have time to find and quote the regs, but I'm pretty sure there is verbiage about not being able to manually input points - must be an internal database. Similarly, IIRC, the 'approaches' in non-certified units are FAF to runway only - no initial, missed segment, etc.
 
While I agree that planning to use a handheld GPS for an IFR approach is not legal. There is at least one series that has all the IFR approach plates, including all fixes and missed in them. Those from aviationsafety.com, I have been using one of their units for several years and appreciate seeing the IFR guidance on the GPS.
Bill Greenley
 
Ok, sooooo...

If I were to use my VFR GPS to shoot the approach...

INVERTED!

Would I have to follow reverse horizontal CDI indications like I was on the backcourse, but my vertical navigation would be normal?

Also, if I put gear down, would I really be putting GEAR DOWN?!?

Can anyone help me with this?

;). CJ
 
60av8tor said:
Don't have time to find and quote the regs, but I'm pretty sure there is verbiage about not being able to manually input points - must be an internal database. Similarly, IIRC, the 'approaches' in non-certified units are FAF to runway only - no initial, missed segment, etc.
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AIM 1-1-19

d. General Requirements

1. Authorization to conduct any GPS operation under IFR requires that:

(a) GPS navigation equipment used must be approved in accordance with the requirements specified in Technical Standard Order (TSO) TSO-C129 (as revised), TSO*C196 (as revised), TSO*C145 (as revised), or TSO*C146 (as revised), and the installation must be done in accordance with Advisory Circular AC 20-138, Airworthiness Approval of Positioning and Navigation Systems. Equipment approved in accordance with TSO-C115a does not meet the requirements of TSO-C129. Visual flight rules (VFR) and hand-held GPS systems are not authorized for IFR navigation, instrument approaches, or as a principal instrument flight reference. During IFR operations they may be considered only as an aid to situational awareness.
 
I have used my Garmin 696 to shoot GPS approaches under VFR. While it is definitely not legal for IFR, I recommend that those with a similar set up (I also have a SL-30) practice this as it is quite doable if needed. It takes a bit of time to enter in all the fixes manually, but you can shoot the approach quite safely, if conditions require it. Examples are emergencies and low fuel states where GPS only approaches are the only option. Might save your hide some day.

Also, the 696 is quite capable for DME and ADF work along with a vor or ILS. Not legal, but should be practiced, IMO.

-John

cccjbr6 said:
I have heard that to avoid the expense of adding a certified radio like a Garmin 430W to a panel with a G3X, some are mounting a Garmin handheld like an Aera with a WAAS engine to enable them to shoot GPS approaches. Is it legal in experimentals to shoot a GPS approach with such a setup in IMC?
Click to expand...
 
PCHunt said:
Essentially, in a bona-fide Emergency, you can break any and as many FARS as you need to be able to safely conclude the flight.

You obviously need to be prepared to justify your actions, if requested by the administrator.
Click to expand...

I would like to add, that regardless of your explanation, I suspect a citation will follow.

A story I was told during one of my check rides (the oral part). paraphrased:
A pilot flying a seaplane with a transponder/encoder that was well past it's biannual certification, by about 20 years, had an engine out emergency. during the normal operations for this pilot/plane, the transponder was never used. During the engine out emergency, the pilot turned on the transponder to squawk 7700. The Pilot landed safely and was later cited for his use of the non-certified transponder.

But, I suppose I wouldn't worry about paying fines till I was safe on the ground.
 
the darwinian instinct is strong with some, weak with others

I will share my insight on this, it's a bad idea.
 
A question earlier in this thread didn't seem to get the attention it deserved so I'll toss a bit more grist into this mill.

There often seems to be a great misunderstanding of the terms WAAS and RAIM. Many folks believe that a WAAS receiver is what's required to shoot approaches when in fact it's RAIM which assures the integrity of the position fix necessary to shoot a precision approach. Sure, WAAS gives you the accuracy that's needed, but without RAIM to monitor the integrity of your position fix, WAAS might happily guide you right into the side of a mountain.

With this having been said, a WAAS-capable hand-held will probably get you down in an emergency and it's almost certainly better than blindly descending through the clouds. A RAIM-equipped gives you the assurance that you aren't unwittingly following an incorrect GPS fix. It's this differentiation which makes the approach-certified panel mounts the only viable option currently available to us for GPS precision approaches.

(If you don't believe that GPS can lead you astray, buy me a beer and I'll tell you a story about how a GPS receiver once put my position over 400 miles away from reality. That was a sobering insight into why we pay the big bucks for our approach-certified GPS units.)
 
bret said:
Also, do hand helds have RAIM?
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No handheld produced that I am aware of supported RAIM. And since many handheld GPSs today utilize WAAS, it's not required.

WAAS supersedes RAIM; the integrity detection built into the WAAS standard means that RAIM is for the most part obsolete. It *may* still be used if the WAAS system is unavailable, but when WAAS is active it provides better integrity monitoring than RAIM can.
 
Canadian_JOY said:
There often seems to be a great misunderstanding of the terms WAAS and RAIM. Many folks believe that a WAAS receiver is what's required to shoot approaches when in fact it's RAIM which assures the integrity of the position fix necessary to shoot a precision approach. Sure, WAAS gives you the accuracy that's needed, but without RAIM to monitor the integrity of your position fix, WAAS might happily guide you right into the side of a mountain.
Click to expand...

I don't think this is correct. Details at this link but essentially WAAS provides built-in integrity monitoring which make RAIM unnecessary.
 
In the event WAAS isn't available, RAIM is the only thing that stops you from using a potentially incorrect position. That's why RAIM is part of the certification requirements - it's the suspenders to WAAS's belt. No handhelds do RAIM, so if WAAS is lost, they're not able to determine whether a position fix is valid or not.

I've seen WAAS come and go in flight. Having RAIM is a darned good thing.
 
Canadian_JOY said:
In the event WAAS isn't available, RAIM is the only thing that stops you from using a potentially incorrect position. That's why RAIM is part of the certification requirements - it's the suspenders to WAAS's belt. No handhelds do RAIM, so if WAAS is lost, they're not able to determine whether a position fix is valid or not.

I've seen WAAS come and go in flight. Having RAIM is a darned good thing.
Click to expand...

The point is that WAAS actually does more than just provide a highly accurate position - it also ensures integrity. You're right in that if WAAS isn't available, RAIM is used, but when WAAS *is* available, RAIM is not used.
 
So to get to the point, can we work up a list of affordable, legal WAAS GPS units that can be connected to our experimental EFIS units and comply with ADS-B going forward?
 
SHIPCHIEF said:
So to get to the point, can we work up a list of affordable, legal WAAS GPS units that can be connected to our experimental EFIS units and comply with ADS-B going forward?
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Affordable? IMHO there are none (that is, comparing the actual cost to what is needed to do the job).
You will need to meet the requirements of FAR 91.225 and 91.227. These, in turn, specify certain TSOs be met (154c and C166b, I think). As has been discussed previously, these TSOs (which are lists of specifications, tests, etc) are so complex that it is not feasible for an average person to self-certify. Some of the specifications deal with management controls over software writers! (Now you see why these things are expensive- grossly excessive paperwork). A non-WAAS box cannot meet the TSO but having WAAS is not enough.

As far as I know: Freeflight and Navworx have TSOed gps units. The Garmin 400W/500W series boxes meet the TSO (software upgrade may be required). I can only guess that the GTN series will work too??

BTW, until 2020 you may run any gps into your ADSB out box. There's a data bit that tells the FAA the data is from a non TSO source.

Edit: Garmin literature says yes, GTN series will work.
I keep swapping tso numbers. I think the gps needs to meet 145, the whole system 154.
 
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Reading this you can also go to Fltplan.com and for a flight get a RAIM verification.

It is too bad that the FAA is so far behind technology. When I got my instrument rating in 1970 we had to shoot ADF approaches. If we hit the airport we did good. After a lot of practice you could get to 1/2 mile. But 3 meters with GPS is not good enough... go figure.

The other item I have not seem mentioned is that you can not use Just GPS to go fly IFR even if certified with WAAS. You are required to have VOR receiver. Since GPS can be shut down, they want to assure that we all have the capability to get on the ground.

Toss in another. If you have only a single VOR you can fly to any Airport that has a VOR approach via airways. If you have Dynon's with their non certified WAAS receivers.. you still legally can not use them to do Point to point navigation and would have to do your route via airways and the destination would have to have a VOR approach... go figure. Unless it is a certified GPS unit and you have VOR capability your out of luck.

The FAA knows that a lot of experimental folks are flying IFR with Non Certified equipment. with out MEL's and other documentation. Thankfully there has not been a rash of accidents. I was told this by an inspector when I got my repairman's certificate in the Atlanta FSDO, I specifically address this whole topic with them. I have more problems with pilots flying IFR with out the ratings....I have seen several of these doing BFR's.... instrument time logged and only holding a PP rating did I see this correct in the pilots log book? $%@^@% and I am in our corporate jet trying my best to uphold every regulation..... and other folks are flying in the clouds with out ratings.....because they can get away with it and if they never have an accident... no one would ever know.

WE are blessed with so much capabilities and limited by but what if's. I am sure glad the pilots of the twenties and thirties and forties were bold landed in fields worked on their engines and took off again flew IFR by A and N morse code signals. If it was not for the pilots then... our aviation would have never advanced to the point that the FAA wanted to govern every aspect of it.
I feel so sorry for the folks with certified aircraft that want to use Dynon's, GRT's, GARMINS G3X but can not put them in because of the stupid regulations. More capable. More situation awareness, More traffic capability at a fraction of the cost of Aspen or Garmin for certified aircraft. And as reliable as any King or Bendix and steam gauges. Don't see too many Garmin 600 or 1000 packages in RV's. I think they are excellent packages... but not for the experimental world. I know they could be sold a lot cheaper if the regulations were rewritten... but perhaps not... we got the FAA to limit the liability of manufactures years ago to 10 years, they promised prices would drop..... hummmmmmmm Did Not happen.... we were in an ecomonic boom.

Just venting.....

Jack
 
Actually you do not need VOR if your GPS is an IFR approved WAAS capable unit. You do need other nav means if it is not WAAS.

Additionally, FltPlan.com gives a RAIM prediction for your route; not necessarily actual RAIM.
 
Affordable?

I will upset some of you here, but when I see folk wanting to cheapskate on IFR, I really have to think....should you be flying IFR at all?

Just like the argument...its only light IFR......there is NO SUCH THING. It may be light IMC on that day, but the IFR means Instrument Flight Rules.

Everything from power sources to nav and com systems needs to be a little better than a simple vfr plane.

Wait till you are in solid and serious IMC and over rugged country and even a simple failure like an alternator will get your pucker factor up a bit.....even with an hour or so of theoretical battery life.

This is never the time to be quibbling over a few thousand bucks. With all the great EFIS and backup strategies you can build in an ABE today, really safe IFR flight is so cheap now it is unbelievable. Compare what you can do with a couple of sky views and a GNS430W or GTN650 Vs a G600 in a Bonanza. The price difference is so huge you can buy an RV4 or a car with the change.

Unless you have a different mindset you have no right in IMC, the people you fly with and those on the ground deserve it. That is why the rules for IFR are the way they are, and were written in others blood first.
 
Dave,
I do not mean to imply we should be flying ifr with automotive gps units; but otoh: In the US it has always been legal to fly IFR under part 91 using VORs, DMEs, ADFs, MBs - everything except gps - which were not TSOed. And I know of no statistical evidence that non-TSOed equipment has failed more often, or contributed to accidents, any more than TSOed boxes.
Back to the original subject - ADSB out- all these gps boxes need do is figure the position. There is no database, no approaches. The TSO process has made these gps units 10 times more expensive than need be.
 
flyinga said:
Actually you do not need VOR if your GPS is an IFR approved WAAS capable unit. You do need other nav means if it is not WAAS.

Additionally, FltPlan.com gives a RAIM prediction for your route; not necessarily actual RAIM.
Click to expand...

Technically, you do need a VOR if your gps is approved under TSO 129; no other nav equipment is required if your gps is approved under TSO 145. As a practical matter this is non-WAAS vs WAAS.
 
Canadian_JOY said:
...(If you don't believe that GPS can lead you astray, buy me a beer and I'll tell you a story about how a GPS receiver once put my position over 400 miles away from reality. That was a sobering insight into why we pay the big bucks for our approach-certified GPS units.)
Click to expand...

A couple of years ago I linked up with another buddy on a cross country mission. My airplane was equipped with a G530 and his with a G696. We were in radio contact and calling out our relative positions on the same magenta flight plan. We soon discovered that we were the same distance from our next waypoint and both claimed to be directly on course. A brief search of the sky finally found him out about a mile off my right wing. Turns out that both GPS units were showing on course, neither was showing an error, yet we were a mile apart. His unit went in for service the next day and was repaired. More than a little scary.
 
Not sure if this has been mentioned before, but, WAAS is not what it is about. Many non TSO'd hand helds have WAAS, from memory the G296 from over 10 years ago. But this has not much to do with being a TSO 146 navigator.

These three letters do..... FDE. And E being a biggie, which might have had something to do with the 400 mile excursion mentioned above :eek: .
 
David;
I asked a simple and fair question and you came riding through on your high horse making presumptions I never intended.
Great lazy statements of opinion, but no helpful comments on compatible products that work with experimental EFIS, satisfy the intent of the law and possibly remain useful for a few years as the Nextgen system gets implemented.
 
SHIPCHIEF said:
David;
I asked a simple and fair question and you came riding through on your high horse making presumptions I never intended.
Great lazy statements of opinion, but no helpful comments on compatible products that work with experimental EFIS, satisfy the intent of the law and possibly remain useful for a few years as the Nextgen system gets implemented.
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Scott,

This post is aimed directly at you, hence I have copied and addressed you, my earlier post was wide reaching and not aimed directly at you. So please no slagging about high horses. Why did you feel it was that way to begin with? (Rhetorical question only).

So that you understand my position on this there have been countless posts and threads on similar topics over the years and I have seen all manner of really poor and dangerous advice.

My post was a broad sweeping statements that is true, and not just opinion but reality.

To be specific, here are some answers if you want to be flying IFR and ADSB compliant down the road. Of course VFR only can get blind boxes and a suitable transponder and away they go. If you look at ADSB around the world the fast adopters were down here so we have been exposed to this for a long time, and we have much tighter and earlier requirements so this is something I am familiar with. Next Tuesday I am meeting with Air Services Australia and a major USA company on future developments in this area, (at my expense) so I do have a bit of skin in the game.

Garmin GNS and GTN range
Avidyne IFD
Bendix King KSN range

These are the ones for our kind of machines. None are cheap and the lowest cost will be a good second hand GNS430W
 
Bob,
Thanks, I could not find the reference. I knew that our Hawker which has GPS required another method of Navigation since it is not WAAS approved.

I was under the wrong impression that this still applied.

Jack
guess I will be looking at Oshkosh to add a WAAS GPS to my RV. I think our mechanic is already addressing the issue of WAAS on our Hawker.
 
It's not just integrity...

The comments about WAAS, RAIM and other integrity checks are right on the mark, but IFR GPSs also have specific requirements to sequence waypoints on the approach, and to scale the max CDI deflection based on approach segment.

This accident - http://www.ntsb.gov/aviationquery/GenPDF.aspx?id=IAD03FA005&rpt=fi - happened in 2002 at the airport where I took my Private checkride. I recall some additional discussion about it at the time in IFR Magazine - the pilot was using an AnywhereMap PDF/GPS system to shoot the approach, and the system was displaying CDI guidance which was appropriate to tracking a VOR, but flying a GPS approach. That, plus being below the minimum altitude for the segment, was enough to catch a large antenna near the airport.

There are a lot of gotchas trying to fly a GPS approach using non-approach-certified GPSs, and I'm sure none of us know what they all lie.

Dave
 
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Just to muddy the water a little more........ I was at an AOPA seminar in Cincinnati a few years ago and the subject was hand help GPS navigators. We were told you can use a handheld GPS for point to point enroute navigation on an IFR flight if you are in radar contact with ATC and they approve it (going direct). It is sort of like a radar vector to your destination. Of course you have to be prepared to fall back on your approved NAV source if radar contact is lost - like VOR navigation.
 
Scott Hersha said:
Just to muddy the water a little more........ I was at an AOPA seminar in Cincinnati a few years ago and the subject was hand help GPS navigators. We were told you can use a handheld GPS for point to point enroute navigation on an IFR flight if you are in radar contact with ATC and they approve it (going direct). It is sort of like a radar vector to your destination. Of course you have to be prepared to fall back on your approved NAV source if radar contact is lost - like VOR navigation.
Click to expand...

Technically, you are asking for a radar vector. That's how it works.
 
bkthomps said:
the darwinian instinct is strong with some, weak with others

I will share my insight on this, it's a bad idea.
Click to expand...

Nailed it.


Why is this a four page discussion? You can NOT shoot a GPS or RNAV approach without a certified receiver and installation. No handhelds, no iPads, no cellphones, no Foreflight, etc.

People doing dumb $&!@ like this is a sure fire way to get yourself (or worse your trusting innocent passengers) killed.
 
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One other consideration. Our 696 which has one of the better GPS receivers gets considerable interference from our AFS 4500 screens. Signal strength drops in half when the screens are turned on. I am sure that is another issue the FAA would have if a portable was used for a approach. It's performance could change based on location.

George
 
VFR GPS

I used a VFR GPS off and on for three years in Chicago Center airspace on IFR flight plans. I would either put VFR GPS in remarks section of flight plan or simply tell center I had a VFR only GPS.
I also did a two hour plus high altitude leg before GPS where I plotted offsets from VOR's for the direct routing. Center never bothered me or issued a change of heading, probably because it was 2 am.
The best low cost entry into IFR GPS I can find is the King KLN90B. These are showing up for 25-50% of the cost of a Garmin 430 and about half the cost of a Garmin 300. Apples to oranges because the King does not have a vhf nav com included.
In reality the difference between WAAS and IFR certified non WAAS is the ability to make instrument approaches to lower minimums IN SOME CASES with the WAAS.
The WAAS does not seem to lose the signal as much as the non WAAS.
From a practical standpoint, based on five years of flying both WAAS and non, I became convinced that in an emergency the non WAAS would take me to 200' and maybe even 50' if there were no other options, such as a load of ice or engine out on a twin. Because of the environment and distance between airports I practiced this to 50' hundreds of times and it was always perfect with the non WAAS.
 
I don't understand what you're saying. The non WAAS box has no glide slope, so if you're descending to 50' you're just hoping there are no obstacles? Or you're descending based on being on top of an ILS? or over the runway? or over Kansas?

The big difference between the two is LPV approaches, with glide slope guidance. Enroute little difference. Of course with the King you must have a VOR on board, any alternate required must have a non gps approach you can use, etc.

All in all it's not a bad trade off for the price - until 2020, when you'll need to have a TSO'd 145 (WAAS) box of some sort for ADSB. I think we're all holding our breath hoping the prices come down (that includes the FAA, which will look like fools if the UAT option ends up costing more than the mode S-ES route).
 
Time for the non IFR guy to ask a question. I know that expensive gps units like 430W etc are all-in-1 navigation units. But for you experimental EFIS guys, I was under the impression that all the GPS unit does (assuming you are not connected to a 430W or similar) is supply your 3d position to your EFIS boxes, be they Dynon, GRT, AFS, and then it is the EFIS box that stores all the approach data and does all the magenta line creation. Is that totally wrong? Maybe I am confusing this with the ability to try to hand fly an approach in IMC using synthetic vision.
 
CAT,
The certified GPS stores all the databases and does all the navigation calculations like how far to the left or right you are from your course and how off the glideslope you are. The EFIS then displays this info (like a mechanical CDI/HSI would).

A TSO'd GPS isn't technically a GPS, it's a navigator. That means all the software that calculates navigational data and the databases must be certified too. It's a lot more than just certified 3D position.

Here's a post we made on this a while ago with more detail on what is required for IFR in an experimental:

http://dynonavionics.com/cgi-bin/yabb2/YaBB.pl?num=1362597418
 
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