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Data Integrity - NOT! Still relying on paper.

nomocom

Well Known Member
I've left two airports in the past year, humbly and as quickly as I could manage. This was at least partly because I found it expeditious to rely on electronic records. In both cases, the Jep data indicated public airport, however once on site, I found it to be private. In the TX case, in spite of Jep and Foreflight reporting it public, it was clearly not public, as the local Sheriff introduced himself (that's a story in itself). At the Canadian strip, well it is public, in a limited sense, as described below. Interestingly, while Radium Hot Springs airport is listed as public, my friends picking me up found the roads to the airport clearly posted as private and arrived at the strip very much feeling like a trespassers.

So to get a bit more insight, I inquired of Jep customer service (abbreviated exchange)

How does Jeppesen go about determining if an airport is public or private? .........
Guthrie TX 6TE6 and a Canadian airport- Radium Hot Springs CBL6

And the reply...
___________________

Thank you for your question on CBL6 and 6TE6.

Airport CBL6, is correctly captured as "public" even though it is privately owned. You should understand the term "public" as "open to the public" or "for public use" and that is how Canadian pilots expect us to show this information. Jeppesen uses source documents (in this case, the Canadian Aerodrome Facility Directory) issued by the Aeronautical Authority of each country to determine if an airport is private or public use.

As a policy, Jeppesen does not capture private US airports unless the owner makes the request from us. Then they need to provide all the current information related to their airports. In the case of 6TE6, I found that it should be captured in the database as "private". It will be corrected in database cycle 1010, effective 23 Sep 10......

____________________________________

I will add here that I'm not headed out with only the Garmin 296. In both cases, I had other reference materials. In Canada, among other things, I had the VNC and a PDF reader with the current official- Canadian Airport Charts. Unfortunately, the file does not include all the airports, so to visit a small airport and cross check Jep data, you need to have the Canadian Flight Supplement handy (not available in PDF). Texas, I had Foreflight (running on the iPhone) and the G296 both saying public, I didn't take the time to check the official sources, both the sectional and the AFD would have given me a heads up that it was private.

Soap box warning!
Don't we need all "official" airport documents available in PDF format, so as we fly about with these GPS's we have an ability to check the the 3rd party data against the official data? While I'm happy to admit that Jep gets it right most of the time, it's still not the official published data and the regulatory burden is on the pilot to use the correct information, just as the Garmin startup script reminds us at each boot.

Am I the only one wondering a bit why I spend money on 3rd party data updates?

Comments, brilliant solutions?? :D
 
I would be interested in the full story around your landing at 6666 Ranch Airport. :D

That aside, I'm not sure...without checking the official sources of course. I'm currently hedging towards the MGL stuff in my future plane, which could show the raster VFR chart and thus the "pvt".

For the 4 letter airports I typically double-check myself out of habit, as so many are private. (But many will happily grant you PPR permission too.)
 
The "official" record as filed...

I would be interested in the full story around your landing at 6666 Ranch Airport. :D

That aside, I'm not sure...without checking the official sources of course. I'm currently hedging towards the MGL stuff in my future plane, which could show the raster VFR chart and thus the "pvt".

For the 4 letter airports I typically double-check myself out of habit, as so many are private. (But many will happily grant you PPR permission too.)

...with the FAA came be found on-line here - US airports only -

http://www.gcr1.com/5010WEB/airport.cfm?Site=6TE6

6TE6 is indeed private.

Just change the identifier at the end of the link above to get any airport...

Often a note is in the "Comments" tab for PPR (Prior Permission Required)
 
That aside, I'm not sure...without checking the official sources of course. I'm currently hedging towards the MGL stuff in my future plane, which could show the raster VFR chart and thus the "pvt".
I've installed the sectionals on my MGL's and I really like having "sectional" info at hand. Big screens and zoom allows you to actually read it too.
 
I usually call any airport I've never been to before takeoff if I intend to land there. If I land on a whim (or a full bladder), I just look for the biggest runway around - those are rarely private and in any case more likely to have a restroom.

In an emergency, I don't give a rat's backside whether it is private.
 
Interesting,

I plan to places I know are public and have the services needed and I digress I do it off paper charts but:eek:, If I was "mislead" I would say something to Jep:mad:, but how could I be mislead??:rolleyes: I paid them $600 plus for my years subscription for my MX-20 and GNS 480..how could It be wrong? :eek: My next plane will have Robs Advanced Deck (AFS) system, I have the 3500 EFIS and Engine monitor right now and love it, at least his advanced system has charts and mapping for free (I think). No need for the MFD or the capability of the 480, but I admit I love the 480, now that I know how to use it;)
 
Airnav shows 6TE6 as private, PPR.

My Air Chart book (paper!) shows it as Private.

Unknown what my GNS 430 shows.
 
Paper OK too.

I like having a sectional on board. Had to use it 2 times in the last 2 years because the GPS quit far from home. If nothing else, looking for lakes, railroads, and small towns on the paper is something fun to do when the autopilot is on, the iPod's cranked up and I'm bored as **** at 8500 feet.

However, using 1/2 the baggage capacity of a PC-12 to haul around all of North America's paper IFR Jepp plates for my old job was another ridiculous story altogether... :rolleyes: Electronic charts are awesome, but you'd think that with that hefty subscription rate, Jepp would get their act together! Thanks for the warning!
 
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I just checked my Garmin 430W with recent Jeppesen database and 6TE6 is listed as Public.
 
Hmmm... official available through GCR?

The official record as filed with the FAA came be found on-line here - US airports only -

http://www.gcr1.com/5010WEB/airport.cfm?Site=6TE6

6TE6 is indeed private.

Just change the identifier at the end of the link above to get any airport...

Often a note is in the "Comments" tab for PPR (Prior Permission Required)

Gil,
I'm honestly not very excited about using data from what looks like another 3rd party provider- in this case GCR & Associates. This http://www.airportiq.com/Login.cfm seems like another offer to take our money when the official data should be, and likely is already available, no? Is there more to this story, as in the FAA farmed out official record keeping? I browsed around GCR's website and while it's clear they provide aviation consulting, I didn't see any reference to them being the official source for airport data.
I would think official would be this- https://airports-gis.faa.gov/airpor...rportDisplay.jsp?category=nasr&airportId=6te6. Found this resource by looking at the info provided under the front cover of an AFD.

Also...http://aeronav.faa.gov/index.asp?xml=aeronav/applications
Downloadable digital products, including sectional TIF files that would go easily on an iPad. AFD info appears to be broken up and not easy to get a complete pdf file. That's to bad, as with the iPad, it would be very usable.
 
Stan - I agree on the third party bit...

Gil,
I'm honestly not very excited about using data from what looks like another 3rd party provider- in this case GCR & Associates. This http://www.airportiq.com/Login.cfm seems like another offer to take our money when the official data should be, and likely is already available, no? Is there more to this story, as in the FAA farmed out official record keeping? I browsed around GCR's website and while it's clear they provide aviation consulting, I didn't see any reference to them being the official source for airport data.
I would think official would be this- https://airports-gis.faa.gov/airpor...rportDisplay.jsp?category=nasr&airportId=6te6. Found this resource by looking at the info provided under the front cover of an AFD.

Also...http://aeronav.faa.gov/index.asp?xml=aeronav/applications
Downloadable digital products, including sectional TIF files that would go easily on an iPad. AFD info appears to be broken up and not easy to get a complete pdf file. That's to bad, as with the iPad, it would be very usable.

But in this case, the FAA Form 5010 is the Official Airport Master Record, and yes, it does seem to be farmed out to a third party as a data base keeper.

My link to the 6TE6 came from a FAA web site that linked to the entire data base.

Your FAA link above does not seem to cover all of the data that is in the master record.

I know when our airpark wants to change FAA data, it is the Master Record (Form 5010) that we edit - I believe it is the 5010 data that feeds the AFD, not the other way around.

In this case, I think the third party link is the official data.

UPDATE

This FAA newsletter seems to confirm that the 5010 data is the "master", but is being converted to the Airport GIS system you linked to at some time in the future (page 3) - it's an old newsletter though...:)

https://airports-gis.faa.gov/public/data/newsletters/2009_1Q.pdf

The GIS system is more geographic (GIS = Geographic information System) and would certainly be the data that is fed into the GPS data bases.
 
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Airnav shows 6TE6 as private, PPR.

My Air Chart book (paper!) shows it as Private.

Unknown what my GNS 430 shows.

My KLN-94 shows it public - I always fly X-C with a paper chart open following my course out of habit, I flew over 6TE6 twice over this past weekend, and noticed the paper chart (current) shows it private. There was another field where this was true as well, but I don't remember off the top of my head what it was.
 
iPad apps and data integrity

AFD info easily available on Ipad using Skycharts Pro and other apps. Not quite free, but almost

Well, that's encouraging. I've got an iPad on order and have used my iPhone for over a year, sometimes with a Foreflight subscription. For me, more of my concern centers on the data integrity, than whether or not it is free or not. I haven't used Skycharts, but if they can take the FAA data and present it without introducing errors, and add some value- likely usability, then I'm interested. If they've got a human sitting at a keyboard transcribing the data, then I'll likely pass and look for a product that has better data integrity. Not dissing the wage earner here, they no doubt would do a better job than I would at the keyboard, I just don't see it as a workable way to preserve the data quality.

So, basically I've got an issue with the way information currently seems to flow. FAA collects and publishes the data. 3rd parties "harvest" the data, repackage it, and then sell it (with disclaimers). There's no conspiracy here, the companies are well intentioned, and are providing a worthy service. It just isn't going to be the same as looking at the master file- 5110 or whatever it happens to be.

Airguy...
Interesting on the KLN database... is that a Jep product as well?
 
Speaking as someone who gets the raw FAA data (I subscribed when I was toying with rolling my own database for the Blue Mountain EFIS), it is very common to get my subscription DVD and then get an errata sheet a few days later. So much for your master file. As a long-time computer professional (for a few years my title at IBM and consulting was Data Base Analyst), as databases increase in both size (amount of data) and complexity (types of data and interrelation) the chances they will be error-free drops rapidly. This is nothing new; paper databases suffer the same way and lack some of the error-correcting tools that are available for 'soft' databases. And printing a digital database does not necessarily make a cleaner copy, because the printing process itself can introduce errors (as can publishing to other media). My point is that 1) paper is not necessarily better (or worse) and 2) no data is totally reliable. I love my EFIS with its synthetic vision but I still spend most of my time looking out the window for cumulogranite (not to mention those movable hazards that don't show up in any database - yes, I mean you other pilots! ;))
 
Data reconciliation by 3rd parties, is it happening?

it is very common to get my subscription DVD and then get an errata sheet a few days later. So much for your master file............ as databases increase in both size (amount of data) and complexity (types of data and interrelation) the chances they will be error-free drops rapidly. This is nothing new; paper databases suffer the same way and lack some of the error-correcting tools that are available for 'soft' databases.........And printing a digital database does not necessarily make a cleaner copy, because the printing process itself can introduce errors (as can publishing to other media). My point is that 1) paper is not necessarily better (or worse) and 2) no data is totally reliable.

Good points...I appreciate a professional data base analyst weighing in here.
A couple thoughts in response to your comments. I see your point about "paper" not necessarily being better. This has helped me narrow my criticism by asking then, what constitutes good data?

I have a preference for FAA data. What is that based on? Maybe it is simply the "source data" and I see it as less likely to contain errors.

When the FAA data shows "private" and a 3rd party data shows "public", what is implied concerning data reconciliation protocols? I think a likely implication would be that the 3rd party data isn't getting reconciled* against the FAA data, otherwise the error wouldn't have sat in the Jep data for many, many, update cycles. I'd think the reconciliation a fundamental step, if one is going to collect data from one source and use it to repopulate another database..... especially if on is going to charge for it :eek:

*reconciled in the sense that a computer chews through both the FAA data and the 3rd party data- comparing fields and generating a discrepancy list. The discrepancy list is then run through another process that would facilitate fixes or updates. Understandably, the reconciliation of large databases may generate hundreds, maybe thousands of discrepancies, but they still have to be handled if the 3rd party database is going to have quality data.
 
Without getting into the technicalities of this, the type of reconciliation you suggest is expensive (resource-wise) and so trade-off methods are used: interpolation (splitting the difference), value judgments on what data is more likely to be correct (often biased conservatively), curve fitting, and so on. These methods are cheaper and they work. True, they are less perfect than investigative reconciliation, which itself is less than perfect because errors can and do crop up in the reconciling process.

Since I have no idea how Jepp compiles their data, I can't speak to how this error continually crops up but I'd feel comfortable saying it is the exception rather than the rule. If it were not, people all over would be up in arms instead of finding their data useful and a popular alternative to the NOAA set. I'm not defending their error; if it were me, I'd be reporting it to them until they fixed it. I'm just saying I'm never surprised to discover the occasional 'Wups!"; it's just the nature of the beast.
 
Interesting that the error...

..... and so trade-off methods are used: interpolation (splitting the difference), value judgments on what data is more likely to be correct (often biased conservatively), curve fitting, and so on. These methods are cheaper and they work. .....

...is in a simple text field with two possible values.

For the main data (where is the runway?) all of the methods you describe do not sound really suitable for a lat/long value that is fed into the GPS.

Has anyone found a Jepp location error so that the airport isn't there when the GPS says you have arrived?

I say Jepp used source other than the Airport 5010...:)
 
...is in a simple text field with two possible values.

For the main data (where is the runway?) all of the methods you describe do not sound really suitable for a lat/long value that is fed into the GPS.

Has anyone found a Jepp location error so that the airport isn't there when the GPS says you have arrived?

I say Jepp used source other than the Airport 5010...:)
Actually, yes I have. This is exactly what was going on with our private airport. Three years ago after I purchased a 496 GPS I noticed the runway was showing up 3/4 mile NW of the actual location on my new 496. No one from our airport had ever noticed the error on any of their GPS's (it actually was incorrect on the sectional also but how can anyone see that little difference on a sectional?). I suppose because the locals who live/fly out of the airport already know where they live, they never noticed! :p

Once I noticed the error I made several calls. Not knowing anything about how the process of locating an airport works, I started with the GPS manufactuer (Garmin). They informed me they get their data from Jeppeson and I would have to contact them. So, I did, only to find out Jeppeson gets their data directly from the FAA. I was given a number to contact at the FAA to make the correction. After several attempts to get to the correct party within the FAA that had jurisdiction for making such changes I was finally able to communicate to them the error.

I had to send an email that included correct coordinates for the runway. I ended up getting the correct Lat/Long for the center of the runway and also copied a Google Maps screen shot with those Lat/Long figures pined to the center of the runway in the picture and sent it to the FAA. After about 4 to 6 months they had made the correction. At the next available database update I updated the database on the 496. I watched as the correction moved the designator for our airport the appropriate 3/4 a mile SE of its old location.

I am not sure how the incorrect location ever was included in the old data but it did happen. It was a drawn out process to get it corrected but the FAA did finally do so which, in turn, propagated to Jeppeson and ultimately to Garmin.
 
Now that's very cool. I've been happy enough with my GPS and it gets me within visual of an airport, after which I'm back to relying on the good 'ol Mark I eyeball for precision approach;) but I carry a set of charts and AFD with me just in case. The BMA EFIS seems more accurate than our Magellan NUVI, which often has me driving 'off-road' though I tend to excuse that as having more locations to track and roads change more frequently than airports. Oddly enough, the Verizon Navigator app on my phone seems more accurate than the consumer GPS.

But getting back to how accurate even charted info may be, I always take terrain info with a large grain of salt. Even if it was dead accurate, it doesn't take into account things like tree height or movable obstacles. So I give myself a fair margin especially when I can't see, like at night. I enjoyed my Synthetic Vision flying from Sedona to Flagstaff one night; it really kept me oriented to my location in the dark. But I didn't use it as an excuse to fly close to the canyon walls or just skim over the rim; I left a huge margin and depended more on my personal knowledge of the terrain in daylight.

Relating back to the original post, whenever I visit a new (to me) airport, I consult the AFD and then usually, for good measure, visit www.airnav.com/airports which gives me stuff that's not in the AFD and is not bad even if it is not 'official'. Not having had to visit an airport without planning to go there (inflight emergency), I can only say that my plan would be to land without looking or caring about such things as private/public. So far this policy has worked.
 
Too late now...

Actually, yes I have. This is exactly what was going on with our private airport.
.....
I am not sure how the incorrect location ever was included in the old data but it did happen. It was a drawn out process to get it corrected but the FAA did finally do so which, in turn, propagated to Jeppeson and ultimately to Garmin.

...but it would have been interesting to see if the Form 5010 Airport Master Record was wrong on the lat/long.

If it was wrong, then the third party providers did a good job spreading the FAA info....:)

Actually, we can't really ask them to do any more...:)

----------------------------

It looks like not all of the on-line sources have your new lat/long...:)

http://www.pilotoutlook.com/airport/oklahoma/53ok

How long ago did the update actually occur?
 
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...but it would have been interesting to see if the Form 5010 Airport Master Record was wrong on the lat/long.

If it was wrong, then the third party providers did a good job spreading the FAA info....:)
I do not know exactly about the 5010 form. The FAA representative I was talking with at the time did inform me they had the coordinates listed as the old Lat/Long. So I guess the third parties were actually using the provided FAA data.

It looks like not all of the on-line sources have your new lat/long...:)

http://www.pilotoutlook.com/airport/oklahoma/53ok

How long ago did the update actually occur?
Well, I first started the process of contacting someone about it in Oct/Nov 2008. I was notified by my FAA contact in Jan 2009 they would make the change and it would come out in the next cycle which was March 2009. I updated my database on the 496 shortly after that March 2009 cycle and was able to see the change then on my screen. It has been approx 18 months now since the new data was corrected. So perhaps this site does not update their data very often. I would expect that to be one of the "responsibilities" of a site like this to perform.

I would talk about the difference between VFR flight and IFR flight and the relationship we, as pilots, have with the GPS databases we use and how we use them in those different environments. I might discuss the issues associated with not relying on a GPS designed for VFR flight in an IMC situation but, in the case of this erroneous data, the same erroneous data was showing up in an IFR certified database as it was in a database for strictly VFR use. So go figure!

None of us should just blindly rely on something any instrument, or for that matter, any other human, tells us without doing our own analysis first.
 
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