Clearance question V499 / DIANO

FlatPiglet

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Flew GAI to BED the other day. My clearance included ....LNS V499 DIANO T212 LAAYK...

The FMS was sad because DIANO isn't on V499 - the chart shows it as not included even though it was right there. Simple enough since V499 doesn't bend in that segment, but any idea (a) how the computer gave that clearance and (b) why DIANO is excluded from V499?
 
Tell them 'unable' due to DIANO not being part of V499. You might suggest LRP (not LNS) direct DIANO T212 ... as an alternative that you could accept.
 
"Unable due to not direct"
 
What's wrong with just accepting clearance and programming LRP, DIANO, T212...they know where you're going, you know where you are going...why make a big deal of it. There is zero ambiguity. Get on your way...
 
Flew GAI to BED the other day. My clearance included ....LNS V499 DIANO T212 LAAYK...

The FMS was sad because DIANO isn't on V499 - the chart shows it as not included even though it was right there. Simple enough since V499 doesn't bend in that segment, but any idea (a) how the computer gave that clearance and (b) why DIANO is excluded from V499?
Was it LNS or DIANO that isn't on V499? I'm betting it was LNS 'cause airports aren't on airways.
 
Was it LNS or DIANO that isn't on V499? I'm betting it was LNS 'cause airports aren't on airways.
Sorry, LRP not LNS. But the question stands. The clearance was V499 DIANO T212.
 
What's wrong with just accepting clearance and programming LRP, DIANO, T212...they know where you're going, you know where you are going...why make a big deal of it. There is zero ambiguity. Get on your way...
Yeah, that's what I did. I'm just curious if anyone has insight into how the computer would produce that clearance. I prob should have questioned it though as some others have suggested.
 
My guess would be that the ATC computer's database has an error in it.

I can see no reason why V499 'bypasses' DIANO other than it doesn't pass directly over it. . MEA is 4500. All the VOR's defining the intersection, LVZ, ETX, SEG and FQM have airways going to it with MEA's lower than that. It can't be a reception problem. It could be that the LRP012r leading to the CFB193r doesn't pass right smack dab over DIANO. But it sure be damn close. I think the ATC computer(the folk programming it) decided DIANO made sense being on V499 so they just used it. They might not have even noticed that it 'bypasses' DIANO.
 
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I think the ATC computer(the folk programming it) decided DIANO made sense being on V499 so they just used it. They might not have even noticed that it 'bypasses' DIANO.
If the FAA wants DIANO to be on V499 then they can move it so that it is on DIANO. Until then, at least according to Jepp FD Pro, it is not on V499. ATC can't just round it to the nearest airway.

If ATC wants you on V499 until the vicinity of DIANO then the clearance could be LRP LRP012/53 DIANO ...

DIANO is very close to V499 so the difference is small. The threat is that GPS and FMS systems can't be programmed to fly V499 to a fix that is not on V499. That increases the likelihood of programming errors which can produce course deviations far greater than the distance between V499 and DIANO. Just fix it. It's easy to do.
 
I don't have an answer to any of the whys, but looking at a chart, DIANO is less than 200 feet off V499. That's the widest divergence between the airway and a direct LNS DIANO route. Plotted on an en route chart the direct route is within the airway ink, so to speak. Plus DIANO is on T212, V106 and V164. It seems obvious it is where all these airways intersect in the real world despite the V499 bypass.

In the cockpit, I'd just punch in LRP D-> DIANO. Heck, with a 430/530 with no airways, you'd probably never notice the discrepancy. Outside the cockpit, I might send a message to the FAA charting office to ask about the discrepancy
 
Flew GAI to BED the other day. My clearance included ....LNS V499 DIANO T212 LAAYK...

The FMS was sad because DIANO isn't on V499 - the chart shows it as not included even though it was right there. Simple enough since V499 doesn't bend in that segment, but any idea (a) how the computer gave that clearance and (b) why DIANO is excluded from V499?

I believe you're asking why the ATC Flight Data Processing computer can accept a route that does not actually exist. Short answer; because the FDP computer will accept whatever it is told to accept. As an example, V63-191 goes right over KFLD, so the ZAU FDP computer was adapted to accept the airport as being part of those airways.

Why is DIANO excluded from V499? I suspect it's due to a misinterpretation of source documents by the chartmakers. V499 is a straight line between LRP and CFB. V106 and V164 could have been straight lines between VORs, but they're not. They're shallow dogleg routes that cross at a common point, DIANO. I think it likely the intent was to have that common point on V499 as well.
 
If the FAA wants DIANO to be on V499 then they can move it so that it is on DIANO. Until then, at least according to Jepp FD Pro, it is not on V499. ATC can't just round it to the nearest airway.

If ATC wants you on V499 until the vicinity of DIANO then the clearance could be LRP LRP012/53 DIANO ...

DIANO is very close to V499 so the difference is small. The threat is that GPS and FMS systems can't be programmed to fly V499 to a fix that is not on V499. That increases the likelihood of programming errors which can produce course deviations far greater than the distance between V499 and DIANO. Just fix it. It's easy to do.

Yeah. According to the FAA folk who build Airways, it is not on the airway. According to the FAA folk who do ATC, it is. The folk at Jepp and probably everyone else who uses the 'data' it is not, Foreflight goes with the Airway builders also. The quick fix is for ATC to pay a little more attention to detail and quit using DIANO as a V499 fix. The other fix is for the Airway builders to put DIANO on the Airway. That would probably be a fix that would take close to a year or more.
 
Yeah. According to the FAA folk who build Airways, it is not on the airway. According to the FAA folk who do ATC, it is. The folk at Jepp and probably everyone else who uses the 'data' it is not, Foreflight goes with the Airway builders also. The quick fix is for ATC to pay a little more attention to detail and quit using DIANO as a V499 fix. The other fix is for the Airway builders to put DIANO on the Airway. That would probably be a fix that would take close to a year or more.

Maybe. Maybe it's just the folks who make charts who believe it's not on the airway. If the airway builders didn't want DIANO to be on V499 why did they move V106 and V164 from their straight line point of intersection?
 
Yeah. According to the FAA folk who build Airways, it is not on the airway. According to the FAA folk who do ATC, it is. The folk at Jepp and probably everyone else who uses the 'data' it is not, Foreflight goes with the Airway builders also. The quick fix is for ATC to pay a little more attention to detail and quit using DIANO as a V499 fix. The other fix is for the Airway builders to put DIANO on the Airway. That would probably be a fix that would take close to a year or more.
...although, if you try to put it in ForeFlight, it tells you it can't and paints a direct route. A problem if there is a bend along the way; not so much if there isn't, as in this case.

Still another quick fix is for pilots to look at the chart, realize where it is, and take 10 seconds to set up the route in the box manually.
 
Maybe. Maybe it's just the folks who make charts who believe it's not on the airway. If the airway builders didn't want DIANO to be on V499 why did they move V106 and V164 from their straight line point of intersection?

I dunno. It could be just a charting error but I think we'll find out DIANO is not on it. I'm guessing they doglegged 164 and 106 just so they could share a common fix. Why not throw in 499, I dunno. Maybe distance to VOR might be some kind of issue but I'm not seeing it. Someone wake up @aterpster, give him a cup of coffee and get him over here.

EDIT: of course 106 and 164 could have shared a fix without doglegging either of them. Sure looks like sharing with 499 was on someones mind. Charting error could be it but I'm having trouble seeing someone taking the time to deliberately draw that 'bypass' around DIANO without a reason
 
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...although, if you try to put it in ForeFlight, it tells you it can't and paints a direct route. A problem if there is a bend along the way; not so much if there isn't, as in this case.

Still another quick fix is for pilots to look at the chart, realize where it is, and take 10 seconds to set up the route in the box manually.

Of course. That's what you'd have to do anyway with some of the less sophisticated GPS units.
 
I dunno. It could be just a charting error but I think we'll find out DIANO is not on it. I'm guessing they doglegged 164 and 106 just so they could share a common fix. Why not throw in 499, I dunno. Maybe distance to VOR might be some kind of issue but I'm not seeing it. Someone wake up @aterpster, give him a cup of coffee and get him over here.

They didn't have to dogleg V106 and V164 for them to share a common fix, if the airways were straight lines between VORs they'd form a common fix four miles WNW of DIANO.
 
They didn't have to dogleg V106 and V164 for them to share a common fix, if the airways were straight lines between VORs they'd form a common fix four miles WNW of DIANO.
Yeah. Was editing that post as this was coming in. Look up
 
EDIT: of course 106 and 164 could have shared a fix without doglegging either of them. Sure looks like sharing with 499 was on someones mind. Charting error could be it but I'm having trouble seeing someone taking the time to deliberately draw that 'bypass' around DIANO without a reason

Chartmakers do some odd things at times. Sectional charts depict airway intersections but not DME fixes. Take a look at WARWF on the Green Bay Sectional. WARWF is a DME fix, it can be determined by radial and distance from two VORs. But it is depicted as an intersection, an intersection with zero degrees of divergence. That doesn't work, so I contacted the chartmakers about the error. I was told that whenever source documents show two radials making up a fix it is depicted as an intersection.
 
You could've programmed V499 to MAARC then to DIANO. Then, everyone would've been happy (or, at least Skyvector was OK with it).
 
What is TARGETS?

It's software; Terminal Area Route Generation, Evaluation and Traffic Simulation. During my last six years in the FAA I also served as an Airspace and Procedures Specialist. I took some of the tools with me when I left.
 
Revision 11 doesn't show V499. It shows T212, V106, and V164, whether taken from NFDC or TARGETS.
So here's the question: why?

Why is a fix that is an obvious multi airway joining point and off the centerline of one of them by less than the width of a good number of runways not on the airway? Is there some standard for this?
 
I used TARGETS to check the location of DIANO. It's on V499.
I don't know if V499 is supposed to include DIANO or not. The current Jepp and NACO enroute charts show that it does not so all of the RNAV/FMS databases will also show that it is not included. Obviously some mistake has been made, one way or the other.

jepp.jpg NACO.jpg
 
So DIANO got removed from V499 04/02/2015. The Enroute Chart drawers got the word. The folk who do the Data Bases for the GPS's, FMS's and stuff got the word. Looks like the DP Chart drawers didn't get it nor did ATC. While were on the subject, how much difference does that what looks like less than 200 feet make? Will it cause a FMS or some other RNAV(GPS) unit to freak out. It still seems like to small an offset to bother taking it off V499.
 
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