GPS database out of date.. are you slant Golf?

Tantalum

Tantalum

Final Approach
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San_Diego_Pilot
Pretty straightforward question.. this was the one areas of my IR checkride that the DPE wasn't thrilled about.. he still passed me but it made for an interesting discussion:

Q: You get in your plane, the GTN650 is powering up, and you notice the database has expired, in his example it expired some point last month. So not super old, but definitely not current. It's IMC.. do you still go flying? And if yes, what are you filing as.. Slant Golf?

I've since posed this question in person a few times and each time got different answers



My response was yes, the FAR AIM allows for this so long as you've verified that the location of the waypoints, etc., that you plan to use are still, in fact, accurate. The DPE wasn't thrilled with this, his response was that if you get a reroute on your flight, how are you in the air going to go and validate and verify the waypoints..? he also asked that I demonstrate how to actually validate the accuracy of the waypoints one against the other and I wasn't really able to show that either. "Zoom out on the GPS and compare the intersection location against what the current paper chart shows" doesn't actually give you lat / long and prove that a waypoint hasn't moved, etc.


So what say you guys? In reality, in practice.. would you not fly that day?

For the sake of simplicity, assume your approaches are ILS and the plates on your Foreflight are fully up to date.. I'm just talking strictly about filing and navigating in the air
 
I’d still file /G and back it up with the updated database on Foreflight. I could check the nav log to make sure it checked with the 430 flightplan.
 
Somedudeintn said:
I’d still file /G and back it up with the updated database on Foreflight. I could check the nav log to make sure it checked with the 430 flightplan.
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Yeah.. that's basically what I said but he wasn't thrilled about my answer. From a practicality standpoint I'd venture that you're still safer and more proficient doing it that way then reverting back and flying based on VOR radials..
 
/G is for at a minimum enroute and terminal nav. I don’t know what the wording is in the 650 supplement but in the 430 / 530, it’s approved for enroute and terminal with an expired database if the route was verifed with a current reference.
 
Velocity173 said:
if the route was verifed with a current reference
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Yep, but this is what the DPE took issue with, was my explanation for how to determine that. Is simply looking at the route zoomed out against the iPad Foreflight enough..? He was looking for lat/long verification.. and how to do that if I get an enroute reroute
 
What does the GPS Supplement say the waypoints have to be verified against, and does Foreflight meet that criteria?

My supplement says “current, approved data”. Is Foreflight and/or its location data “approved”?
 
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MauleSkinner said:
What does the GPS Supplement say the waypoints have to be verified against, and does Foreflight meet that criteria?

My supplement says “current, approved data”. Is Foreflight and/or its location data “approved”?
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Since the Foreflight IFR charts are the same charts you get from the FAA. That would seem to indicate they are "approved".

So as long as I'm willing to verify the location of the fixes are the same as on the IFR chart, I would interpret that to mean I'm still good for /G
 
donjohnston said:
Since the Foreflight IFR charts are the same charts you get from the FAA. That would seem to indicate they are "approved".

So as long as I'm willing to verify the location of the fixes are the same as on the IFR chart, I would interpret that to mean I'm still good for /G
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How, exactly, do you verify their location?
 
Depending on the make and model of GPS, its AFM supplement may or may not allow using an expired database for IFR, even if you do verify the fixes.
 
Tantalum said:
Yes! My question too!
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Let’s start off with things you can’t do...

My supplement says I can’t use a map display as primary navigation, which would eliminate “zooming out on the GPS to compare positions”.

GPS uses WGS-84 data for bearings, so you can’t measure/read those off the chart and compare them...ever noticed that courses are often a few degrees off?

That puts me in the camp with your examiner...you really need to get lat/long data to compare the waypoints. You can do that from a chart, but that would require so much heads-down time in the event of a reroute that it could easily be considered unsafe. YMMV, but I think having to verify more than a couple of waypoints would be unreasonable.
 
MauleSkinner said:
How, exactly, do you verify their location?
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TLAR....

The easiest way would be to compare the foreflight nav log to the 430 flight plan. If the distances and bearings between the points match then the waypoints haven’t moved.


Also has anyone ever heard of the FAA or ATC MOVING a waypoint? I know they could change an arrival or departure procedure to add a waypoint but I personally have never seen one move location.
 
Somedudeintn said:
TLAR....

The easiest way would be to compare the foreflight nav log to the 430 flight plan. If the distances and bearings between the points match then the waypoints haven’t moved.
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they don’t normally match. They use a different coordinate system.

Also has anyone ever heard of the FAA or ATC MOVING a waypoint? I know they could change an arrival or departure procedure to add a waypoint but I personally have never seen one move location.
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Irrelevant...it doesn’t say anything about verifying that waypoints didn’t move. It says verify them against current, approved data.
 
My enroute routings typically involve VORs and airways which I am confident in saying do not move. For an approach you can look at the date on the plate. If the date is 3 years old all the waypoint names/locations are still valid.

I have seen a 1 or 2 degree variation before but my distances typically match and I am comfortable saying a waypoint has not moved if the flight plans match to a typical level. (which I still have not ever seen an example of - I would like to see one if this happens).

If you are not comfortable with a 1 degree displayed difference than just file /A or /U.
 
Somedudeintn said:
My enroute routings typically involve VORs and airways which I am confident in saying do not move. For an approach you can look at the date on the plate. If the date is 3 years old all the waypoint names/locations are still valid.

I have seen a 1 or 2 degree variation before but my distances typically match and I am comfortable saying a waypoint has not moved if the flight plans match to a typical level. (which I still have not ever seen an example of - I would like to see one if this happens).

If you are not comfortable with a 1 degree displayed difference than just file /A or /U.
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So you’re saying “I’m comfortable with where they’re at” would satisfy the examiner?
 
Isn’t the GPS’s nav data based on the most recent current charts and other paper data?

If so, is there a “list” or textual discussion or description in the newest revision of what has changed since the last revision of each document?

If that’s also true, then can you use that description to figure out if anything along and near your route for diversions or ATC reroute might be different and now inaccurate/dangerous in your out-of-date GPS nav database?

I’m guessing it’s not that simple.

VFR guy...
 
You could have said you’d refuse the reroute to an unknown waypoint and required vectors. It’s stupid and not what you’d do in the real world, but more technically accurate than saying you check it against unofficial data in ForeFlight.
 
Tantalum said:
So what say you guys? In reality, in practice.. would you not fly that day?

For the sake of simplicity, assume your approaches are ILS and the plates on your Foreflight are fully up to date.. I'm just talking strictly about filing and navigating in the air
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MauleSkinner said:
So you’re saying “I’m comfortable with where they’re at” would satisfy the examiner?
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Where did I say that would satisfy the examiner? I was responding to the question in reality what would you do.

The safest thing to do on a checkride is to err on the side of caution. Obviously no examiner could fault you if you said you would NOT be comfortable with that and you either get the database updated or file /A or /U with a current VOR check.
 
Somedudeintn said:
Wow really? Prove to me this is illegal.
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91.9 requires compliance with the limitations in your AFM. Your AFM/Supplement says that if you don’t have a current database, you have to verify all waypoints against current, approved data. It says nothing about doing “what you’re comfortable with”.
 
Tantalum said:
Yep, but this is what the DPE took issue with, was my explanation for how to determine that. Is simply looking at the route zoomed out against the iPad Foreflight enough..? He was looking for lat/long verification.. and how to do that if I get an enroute reroute
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And the DPE gave a reference that specifically states that verification requires comparing lat/ long?
 
Velocity173 said:
And the DPE gave a reference that specifically states that verification requires comparing lat/ long?
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I’m guessing the OP couldn’t cite a reference to the contrary, just like the participants in this thread. ;)
 
For those who are graduates of the US Army RWIEC, remember BANBI? It's a fix that WAS determined three different ways, depending on the route flown and had three distinct physical locations.

A few years ago, the fix was given a Lat/Long and depicted as a single location on the charts. It still has four navaids fixing it!
 
MauleSkinner said:
I’m guessing the OP couldn’t cite a reference to the contrary, just like the participants in this thread. ;)
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But that’s different than trying to enforce something without a reference. As we used to say when I was an IP, nothing wrong with teaching technique, just don’t enforce it as a standard.
 
Velocity173 said:
And the DPE gave a reference that specifically states that verification requires comparing lat/ long?
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His issue was that I didn't really know how to verify it

MauleSkinner said:
I’m guessing the OP couldn’t cite a reference to the contrary, just like the participants in this thread. ;)
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Basically.. and in reality I wouldn't do IMC with an out of date GPS.. because why? Pop the card out and update it. But it was a good discussion and thought exercise and something I couldn't definitely answer.. most of the people I've talked to give the same boilerplate answer that you just have to verify it but no one has ever actually explained how that verification takes place
 
Velocity173 said:
But that’s different than trying to enforce something without a reference. As we used to say when I was an IP, nothing wrong with teaching technique, just don’t enforce it as a standard.
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Which is what’s going on here...all anybody’s come up with are approximations of waypoints, not verification.

I can say that picking my nose verifies the waypoints. Do you have documentation to prove otherwise?

Personally, I’ve found DR to be as accurate as the approximations put forth here.
 
VFR it (probably) doesn't really matter, as you are using visual references for obstacle avoidance, and ATC is expecting you to do that as well. IFR, it is legally a little questionable, because there is no practical way of actuall determining if EVERY fix is current and accurate. The reality is that stuff doesn't usually move, but it does occasionally change names, which can make things interesting. (e.g., "Where the heck did the Binghamton VOR go?") If it's just you, no one is going to know unless there is an incident, but if there is an incident you will undoubtedly get written up with 91.13 at a minimum.

Personally, I'm ensuring I have current data if I'm flying IFR and am expecting to fly GPS-requiring routes.
 
MauleSkinner said:
Which is what’s going on here...all anybody’s come up with are approximations of waypoints, not verification.

I can say that picking my nose verifies the waypoints. Do you have documentation to prove otherwise?

Personally, I’ve found DR to be as accurate as the approximations put forth here.
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Do you have anything to prove that flying when there is a rainbow in the sky is legal?

The legal requirement is to verify the waypoints. Based on what I have seen discussed is there is not a requirement to document a specific method being used. When the FAA has a requirement to use a specific method and document it they specify that. For example VOR checks. Unless you can provide a FAA reference for a requirement to use a specific method of verifying waypoints and the documentation requirements for that method than I don’t understand how you are saying using some other method is illegal.
 
Groundpounder said:
Did you pass? If so, don't worry about it.

Just remember you can't do approaches with an expired DB
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I did, and I appreciate the thought provoking nature of his question, which I think was his point. But I wish there was an actual definitive answer or somebody could say yes, go to this database and you can find the current latitude and longitudes to use
 
Somedudeintn said:
Do you have anything to prove that flying when there is a rainbow in the sky is legal?

The legal requirement is to verify the waypoints. Based on what I have seen discussed is there is not a requirement to document a specific method being used. When the FAA has a requirement to use a specific method and document it they specify that. For example VOR checks. Unless you can provide a FAA reference for a requirement to use a specific method of verifying waypoints and the documentation requirements for that method than I don’t understand how you are saying using some other method is illegal.
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I’m not saying that using some other method to verify waypoints isn’t legal. I’m saying that approximating waypoints and assuming they haven’t moved isn’t verifying waypoints.
 
Doug Reid said:
So if you have a GNS530W, and the database expired a week ago, can you fly an approach using a current approach plate in ForeFlight ?
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Sure, if it's a VOR/LOC/ILS approach. ;)

But if it is a GPS approach, the date at the lower left corner of the approach plate could be a problem if it's less than a week old.
 
Doug Reid said:
So if you have a GNS530W, and the database expired a week ago, can you fly an approach using a current approach plate in ForeFlight ?
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I don’t know about current installs, but the ones I flew didn’t allow it.
 
Doug Reid said:
So if you have a GNS530W, and the database expired a week ago, can you fly an approach using a current approach plate in ForeFlight ?
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depends....if the plate didn't get updated and your database has it....Yes.
 
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