Using an iPad with an IFR GPS to fly an approach

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sixpacker

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Sixpacker
Hello everyone.

I hope this is the right place to post this question. I had an interesting discussion with another pilot today. He told me about a time where he didn't have a RNAV approach loaded in his system (I don't know what he had he didn't say) but he said he just used his iPad and manually entered the fixes into his IFR rated GPS unit and followed along on his iPad to verify. I said he couldn't legally fly that approach and he said BS as long as he can enter the fixes in himself it is fine.

So what is the real answer here?

Thanks
 
No problem ,if you have the plate on the I pad. With the altitudes. Use the waypoint feature on the GPS for the approach.
 
I cant see why it would be a problem if he were to follow the IFR legal GPS. Legally speaking, he would need to make sure the database on the IFR legal GPS was up to date and have a current approach chart. I cant see why it would be a problem otherwise if he were able to enter the waypoints? The Ipad is not legal for IFR approaches, so other than reading a chart, nothing it provides can be regarded as accurate or as reliable as the IFR legal GPS.
 
He needs to read the AFM supplement for his GPS...the part about approaches being "retrieved from the database".
 
You are correct. As it says in the paperwork that comes with those units (see the AFMS which is supposed to be in the cockpit during use of the system), the approach must be retrieved from the database, not loaded manually.
 
MauleSkinner said:
He needs to read the AFM supplement for his GPS...the part about approaches being "retrieved from the database".
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And also understand what "term" means when it shows up (or doesn't show up) on the box.
 
The approach, RNAV SID, or RNAV STAR must be loaded from the database

On an approach, you won't get the proper sequencing from TERM to APPR sensitivity if the approach wasn't loaded from the database so there's no guarantee that you'll stay within the protected airspace and have the required separation from terrain and obstacles.

On approachs and RNAV SID/STARS you also have both fly-over waypoints as well as fly-by waypoints. When you enter the fixes manually they are all entered as fly-by waypoints which will lead to starting turns too soon when reaching waypoints that are suppose to be fly-over.

Aviation really isn't the best activity for people who only like to follow rules that they think they understand.
 
Larry in TN said:
Aviation really isn't the best activity for people who only like to follow rules that they think they understand.
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I think it sums up the whole thing superbly.

and he said BS as long as he can enter the fixes in himself
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I would stay away from this guy, who knows what else he is capable of inventing.
 
Not only should you avoid flying with this guy, but this doesn't say much for the training he received during his instrument rating, unless all his training was /U or /A and he self-studied RNAV procedures after he got his ticket.

Unfortunately, his current technique could literally get him killed if he doesn't keep that needle pretty much bang on during the approach since his GPS is running with TERM sensitivity only.
 
I think you guys are over-reacting. All the GPS database is is a database of WAYPOINT NAMES=LAT/LONG. When you load an approach, it is just a listing of waypoint names and the GPS works the rest of the magic. The ONLY thing that makes the GPS legal versus a non-legal IFR one is the fact that it has RAIM correction, and has been certified for it's positional accuracy. If you had a paper chart (or iPad chart) and loaded each waypoint in individually and then flew the approach, your result would be the exact same. That is, assuming, you are flying a non-precision GPS approach. Why you would do that? I have no idea unless you're just trying to create extra workload for yourself...
 
ahkahn said:
I think you guys are over-reacting.
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I admit it is unclear from the top post how exactly this guy is using his Ipad, IF he is using it as a primary navigation device in IMC then he is a true moron, otherwise this whole conversation is moot.
 
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ahkahn said:
I think you guys are over-reacting. All the GPS database is is a database of WAYPOINT NAMES=LAT/LONG. When you load an approach, it is just a listing of waypoint names and the GPS works the rest of the magic. The ONLY thing that makes the GPS legal versus a non-legal IFR one is the fact that it has RAIM correction, and has been certified for it's positional accuracy. If you had a paper chart (or iPad chart) and loaded each waypoint in individually and then flew the approach, your result would be the exact same. That is, assuming, you are flying a non-precision GPS approach. Why you would do that? I have no idea unless you're just trying to create extra workload for yourself...
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You need to read Larry's post...
 
ahkahn said:
I think you guys are over-reacting. All the GPS database is is a database of WAYPOINT NAMES=LAT/LONG. When you load an approach, it is just a listing of waypoint names and the GPS works the rest of the magic. The ONLY thing that makes the GPS legal versus a non-legal IFR one is the fact that it has RAIM correction, and has been certified for it's positional accuracy. If you had a paper chart (or iPad chart) and loaded each waypoint in individually and then flew the approach, your result would be the exact same. That is, assuming, you are flying a non-precision GPS approach. Why you would do that? I have no idea unless you're just trying to create extra workload for yourself...
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I don't think you understand how GPS approaches work in terms of sequencing and control of indicator sensitivity. For example, there are a lot of changes in how the system displays course deviation and fly-past versus fly-over fixes in the approach modes. Just loading the points in your flight plan doesn't accomplish that. And that doesn't even begin to address the issues of WAAS and RAIM as they operate once the system moves into the approach mode.

The result is that you could think you were within acceptable parameters but actually be outside the protected area on either side of the approach course -- and that could be fatal. Read carefully the discussion on this in the pilot manual for any approach-certified GPS to get more details on this issue.
 
Not to mention there may be a good reason the procedure isn't in the database...the one cockpit discussion I had on this, we requested and were cleared for the approach, but it wasn't in the database. Other pilot wanted me to build it, but I {cough}politely{cough} declined. Upon arrival at our alternate, I found the procedure had been NOTAM'd N/A due to airport construction.

The NOTAM was old enough that AFSS didn't have it, we missed it in the NTAP, and apparently ATC was unaware as well.
 
ahkahn said:
it is just a listing of waypoint names and the GPS works the rest of the magic.
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Yes, but this 'magic' in case of an approach-certified GPS device is knowledge that this is an approach, so it isn't just some sequence of some lat/lons, Ipad has no clue what approach is and how this very special sequence of points must be treated. Also Ipad doesn't provide a correct CDI information which is mandatory for any approach. I only hope there is a big misunderstanding here about how this guy uses his Ipad, otherwise he is an unspeakable idiot.
 
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Tough crowd. It looks like the guy just needs to brush up on some of the finer points, not that he's a menace to everyone in the sky (maybe maybe not :dunno:)

Send him here, we'll straighten him out:wink2:
 
I'm not saying he's doing a correct (or legal) thing if he is flying approaches via his iPad... that is stupid. What I am saying is that knowing how a certified GPS works (notice that I said in my first post above that this would be for a NON-PRECISION only approach) that it is strictly waypoints. Someone mentioned WAAS... that is ONLY for a PRECISION approach. Big difference. In a non-precision setting, an approach is purely waypoints. Assuming this guy is pulling up a plate, loading the waypoints into his 430, and flying it, while technically doable, it seems rather tedious and painful to me. If he's flying an instrument approach while in actual IMC and staring at his iPad magenta line while his 430 sits idle... well... that is illegal and stupid.
 
ahkahn said:
I'm not saying he's doing a correct (or legal) thing if he is flying approaches via his iPad... that is stupid. What I am saying is that knowing how a certified GPS works (notice that I said in my first post above that this would be for a NON-PRECISION only approach) that it is strictly waypoints.
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Except that isn't true. Your really should read one of the manuals on an approach GPS to understand how it really does work, and all the things that change in how the system operates during the approach. Then you'll understand why just plugging in the points doesn't keep you close enough to the course to avoid hitting something.

Someone mentioned WAAS... that is ONLY for a PRECISION approach.
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Again, not true. There are WAAS-required approaches which do not have vertical guidance.
 
ahkahn said:
Assuming this guy is pulling up a plate, loading the waypoints into his 430, and flying it, while technically doable,
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Thanks for explaining the original post to me, I finally got what I was missing, he is loading manually his waypoints from Ipad into .. say a 430 unit. He is using Ipad as a source of data only, got it. Except that it wouldn't work even if this was an ordinary non-precision LNAV approach. All comments by Ron do apply.
 
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Question more on the 'academic interest' side: weren't there in the past old-style RNAV approaches that included coordinates for each waypoint, for which it was legal and appropriate to enter the waypoints manually if you had a legal RNAV system but not an approach database? Or were those all DME RNAV and not GPS?

I got my IR recently and on the east coast, so have mostly encountered the "new style" GPS approaches (and a few of the leftover GPS overlays), and definitely know that they need to be in the approach database for use.

But do any of the old waypoint-by-waypoint RNAV approaches exist anymore? Are they legal for GPS, or do can you only use them with the old rho-theta equipment? (Or am I completely delusional and making them up entirely?)
 
They have been disappearing. There used to be ones at VKX, DCA, MBY, MDW...but they have all been supplanted by RNAV(GPS) (or perhaps RNAV(RNP)) approaches.


TRK and 50I still have them but both have GPS overlays (or GPS) as well.
 
Ron is 100% correct. There is more to any gps approach than just flying from point to point. In particular, RAIM verification isn't there in an iPad, and the behavior of the guidance instrument changes in approach mode.

If you are flying instrument approaches with an iPad for guidance, don't kid yourself. You've just become a test pilot with no advanced engineering planning.
 
Thanks for the responses. I should fill in some more details after seeing some of the replies here. This conversation happened at an FBO. I had just landed (ceilings were about 800 ft so just barely IFR) and commented to this particular pilot who was there that the northbound RNAV approach didn't appear in my G1000 which had the latest Nav data even though there were no NOTAMs saying it was out and it was in my Foreflight. So I ended up doing the southbound RNAV approach and circling to land which was no big deal. This is when he said that this happened to him as well but he just did the northbound RNAV by looking at the approach on his iPad (Foreflight) and then just manually entering the fixes into his GPS (let's say a 430). I personally don't understand why he went to that trouble doing it manually when there was a perfectly acceptable circling approach. The part that makes me wonder too whether he did actually manage to enter all the fixes in is that he said he followed the approach on his iPad. Why do this if he had entered all the fixes into his 430?

Maybe I'm too anal/follower of the rules but this kind of thing really annoys me when other pilots "stretch" the rules like this and endanger the rest of us. Please excuse the mini rant. I'm not out to get anyone in trouble so I won't mention the airport or date. It does sound like the general opinion here is that what he did is not legal. Thanks again for all your comments.
 
One thing you also have to understand is that a lot of pilots are as terrified of circle-to-land procedures as they are of NDB approaches.
 
ahkahn said:
I'm not saying he's doing a correct (or legal) thing if he is flying approaches via his iPad... that is stupid. What I am saying is that knowing how a certified GPS works (notice that I said in my first post above that this would be for a NON-PRECISION only approach) that it is strictly waypoints.
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It's not just a list of waypoints. What about the fact that the CDI sensitivity changes from 1.0 for full scale deflection in terminal mode to 0.3nm when in approach mode? His GPS is not going to go into approach mode, so the GPS is going to remain at RNP 1 instead of 0.3.
 
sixpacker said:
Maybe I'm too anal/follower of the rules but this kind of thing really annoys me when other pilots "stretch" the rules like this and endanger the rest of us. Please excuse the mini rant. I'm not out to get anyone in trouble so I won't mention the airport or date. It does sound like the general opinion here is that what he did is not legal. Thanks again for all your comments.
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It's the same mindset that people use to bust minimums on approaches. Most of the time everything turns out fine, reinforcing their actions. Eventually though it will catch up to you.

IFR flying...well flying in general...requires discipline to rules--even when noone was looking. The NTSB files are full of folks who though they knew more than the rulemakers.
 
mcmanigle said:
Question more on the 'academic interest' side: weren't there in the past old-style RNAV approaches that included coordinates for each waypoint, for which it was legal and appropriate to enter the waypoints manually if you had a legal RNAV system but not an approach database? Or were those all DME RNAV and not GPS?
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Yes, you're talking about the old RNAV(VOR/DME) approaches you could fly on VOR/DME-based rho-theta devices like the King KNS-80. Totally different situation, and as F'Ron said, not many of those left.
 
mcmanigle said:
Question more on the 'academic interest' side: weren't there in the past old-style RNAV approaches that included coordinates for each waypoint, for which it was legal and appropriate to enter the waypoints manually if you had a legal RNAV system but not an approach database? Or were those all DME RNAV and not GPS?
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VOR/DME RNAV, suitable for use on the old KNS 80 for example. And you didn't enter lat/long, you entered frequency/radial/distance. There was no database on the KNS 80, and I'm not aware of any other VOR/DME RNAV units for small airplanes besides the KNS 81. I don't know what the difference between the 80 and 81 was, but I've never actually seen an 81 in person or even in a picture in an airplane.

I haven't shot an approach with a KNS 80 (though I'm tempted to do so now, while there are still a few left!) but I have flown direct on a cross-country flight with it. Not as easy as punching in direct-to, you definitely need a chart so you can plot out the reference points, but it's a pretty cool unit, really an advanced analog computer. I like 'em enough that if I bought a plane with one, I'd probably leave it in as the #2 nav. :)

The way they worked is that you could enter up to four waypoints using frequency (of the VORTAC or VOR/DME), radial, and distance. Then, that point in space acted like a "virtual VOR" and you could twist your OBS and fly a course to or from that point. By entering more than one, you could flip from one to the next. It'd be significantly more difficult than flying a GPS approach loaded from a database!

But do any of the old waypoint-by-waypoint RNAV approaches exist anymore? Are they legal for GPS, or do can you only use them with the old rho-theta equipment? (Or am I completely delusional and making them up entirely?)
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Thanks to Ron for posting the 50I and TRK reference - I haven't seen one of these approaches in a long time, kinda cool that some still exist! I would speculate that the only reason those particular examples exist is that they are "or GPS" approaches with the overlay. It's been around 10 years since I've seen a VOR/DME RNAV approach without a GPS overlay.

Thanks to a little Google-fu, here are the five remaining VOR/DME RNAV approaches, all with a GPS overlay:

TX: KBRO VOR/DME RNAV or GPS RWY 35
IN: 50I VOR/DME RNAV or GPS RWY 27
KS: K59 VOR/DME RNAV or GPS RWY 16
WI: C47 VOR/DME RNAV or GPS RWY 17
CA: KTRK VOR/DME RNAV or GPS-A
 
Another rare situation using manually entered waypoints. Note, emergency only and military.
 

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Velocity173 said:
Another rare situation using manually entered waypoints. Note, emergency only and military.
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How is it possible to do a precision approach using only manually entered waypoints? Do they have a "calculate glideslope from/to this point" function? :dunno:
 
flyingcheesehead said:
How is it possible to do a precision approach using only manually entered waypoints? Do they have a "calculate glideslope from/to this point" function? :dunno:
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Yeah you go into what's called a "GPS Landing Mode" page. You would enter in the waypoint either manually, or bring it up from a database, a corruptible database I would add. Then you would enter MSL altitude for DA, inbound approach course, mag variation & glide slope. You could set it up in route mode, fly to the FAF and engage landing mode. Fly it down just like an LPV.

All of this was done with a VFR only GPS with an encryption (Y) code. Completely illegal to do IMC unless an emergency but we did a bunch of practice during VMC. Never once had one that was off. A nice tool to have in theater with dust storms that come up at a moments notice.
 
sixpacker said:
The part that makes me wonder too whether he did actually manage to enter all the fixes in is that he said he followed the approach on his iPad. Why do this if he had entered all the fixes into his 430?
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My guess? He didn't. He was under the mistaken impression that he would have been legal if he had put them in his 430. I'm guessing he was under iFR ("iPad Flight Rules")
 
What about navigating to an IAF, then IF and FAF for an ILS approach? Must you get VTF in that situation if the ILS approach can't be retrieved from the DB?
 
petrolero said:
What about navigating to an IAF, then IF and FAF for an ILS approach? Must you get VTF in that situation if the ILS approach can't be retrieved from the DB?
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I see no reason you can't do that under the new FAA guidance to controllers allowing them to clear pilots of aircraft with Advanced RNAV equipment to navigate direct to certain points prior to the FAF to enter an approach under certain conditions as long as you won't be using the GPS for lateral navigation on that approach beyond that entry point.
 
Ron Levy said:
I see no reason you can't do that under the new FAA guidance to controllers allowing them to clear pilots of aircraft with Advanced RNAV equipment to navigate direct to certain points prior to the FAF to enter an approach under certain conditions as long as you won't be using the GPS for lateral navigation on that approach beyond that entry point.
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Would that not require TERM sensitivity technically?
 
You'd get TERM sensitivity within 30 or 40nm of the airport if it was your destination in the GPS, even without any approaches loaded.
 
The KNS80 had everything in one box (NAV/LOC/GS/DME). I think the 81 required an external DME.

We had a Cessna (ARC) DME unit in one of the club planes. It had two sets of thumbwheels you set the radial/distance on and you could toggle back and forth between the two. Not too many people used the thing, but the old BROWN AirGuides used to have RNAV coords for all the airports. I showed my wife how to use it when she was a student pilot. Her instructor who already had a no GPS rule for his students had to impose the general NO RNAV after he caught her dialing up the destination airport in that plane.
 
sixpacker said:
Hello everyone.

I hope this is the right place to post this question. I had an interesting discussion with another pilot today. He told me about a time where he didn't have a RNAV approach loaded in his system (I don't know what he had he didn't say) but he said he just used his iPad and manually entered the fixes into his IFR rated GPS unit and followed along on his iPad to verify. I said he couldn't legally fly that approach and he said BS as long as he can enter the fixes in himself it is fine.

So what is the real answer here?

Thanks
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No worries, just fine to do. The database of locations doesn't change, the issue is the self monitoring of signal accuracy and how the GPS deals with inaccuracies. In fact, Garmin has added a Bluetooth feature/option that allows you to program/amend your flight plan with clearance amendments on your panel mounted IFR Garmin boxes with your iPad running Garmin Pilot.
 
Henning said:
No worries, just fine to do. The database of locations doesn't change, the issue is the self monitoring of signal accuracy and how the GPS deals with inaccuracies. In fact, Garmin has added a Bluetooth feature/option that allows you to program/amend your flight plan with clearance amendments on your panel mounted IFR Garmin boxes with your iPad running Garmin Pilot.
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Wow. :dunno:

Perhaps you should read some of the other responses made in this thread and educate yourself and become a safer pilot.
 
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