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Disagreement With ATC Concerning Location/Airspace

Toobuilder

Toobuilder

Well Known Member
In my neck of the woods, I fly in close proximity to several Restricted airspace complexes. While I tend to give them a wide birth, sometimes the best flight plan will come very close to some of the sharp corners of these complexes. Two times recently while going cross country and talking to flight following, I?ve had them tell me to change course because they showed me inside the airspace. This came as a shock to me because the flight plan as well as the 4 separate GPS displays (including an approach certified 430) on board show me in the clear.

Obviously, you are either ?in? or ?out? of the airspace, and therefore ?good? or ?not good?? I?m wondering why the disparity between what the controller sees and what the PIC sees, and what recourse do we as pilots have if there ever IS a ?he said, she said? scenario with the feds.

Any insight?
 
Toobuilder said:
I’m wondering why the disparity between what the controller sees and what the PIC sees
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The same reason ATC is switching from radar to GPS based ADS-B for separation. GPS is considerably more accurate.
 
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I find it frustrating that the tools we have to plan and navigate with are more accurate than those used by the people watching us and passing judgement.
 
Use a position recording GPS unit. Of course that assumes that the restricted area displayed on the GPS unit is correct.
 
Separation from airspace

Another reason a controller might be concerned about proximity to airspace is minimum IFR separation. If two aircraft are operating IFR, one inside a boundary and another outside a boundary, the procedure to maintain a minumum of say 5 miles of lateral separation may be to keep all IFR aircraft at least 3 miles from either side of the boundary, unless a handoff or point-out is coordinated and accepted between the adjacent airspace controllers.

Flight following implies VFR, so this might not apply to the original question, but may apply to IFR.

Not an explanation of why a controller doesn't have your position nailed to less than 10 meters of accuracy, but a possible reason why aircraft are sometimes kept "away from the edges".

Recourse? In the Center environment data is recorded just like voice recordings and kept for awhile, and radar displays can be re-created for investigations, and data can be dumped, lat/longs examined, etc.
 
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Both times this was severe clear VFR with no reports of traffic in the area.

The problems flights were using the KOBTE intersection and HEC VORTAC, which drags me right along the southern edge of the Edwards AFB restricted area, but is in fact on the "good" side according to my on board GPS equipment and flight planning software like Sky Vector and Garmin Pilot. Another problem flight is KOBTE and KTNP, which also comes close, but well outside of a corner of the R2501 complex.

I've since altered my routes to keep me from having the argument, but it seems silly to have to compensate for ATC's shortcomings.
 
Toobuilder said:
I've since altered my routes to keep me from having the argument, but it seems silly to have to compensate for ATC's shortcomings.
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I agree 100% Mike - but then again...the AF guys sometimes carry missiles.... ;)

I tell everyone that our new place out in Carson is 2:30 from Big Bear (by RV) - it could be 2:00 if it wasn't for the Edwards Complex!!
 
yup, welcome to gov't bureaucracy

'If two aircraft are operating IFR, one inside a boundary and another outside a boundary'

There is no IFR inside an active Restricted area, only an inactive Restricted area.

From my time with AF ATC systems, yes there is slop, calibration needed, etc. Improvements in ATC systems move very slowly, glacial pace. Just look at how pathetic a pace NEXTGEN is moving. The controllers are doing the best they can with the crappy tools they are given. Is it frustrating, you bet. Mr Huerta deserves your ire.
Knowing the systems on lots of the jets using the Edwards complex, I would only be running on the border with my head on a swivel, as their SA of the border may not be as fine as yours, although none of them has as tight a turn circle as an RV...fights on.
 
Close too!!!

I fly that route quite often and trim the corner as close as possible. I've had them ask me if I was aware of the space but never vector me. I'm guessing I'm at least a mile clear but if they say anything I'll widen out.

I also made a couple of user waypoints in the 430 and 496 to help stay clear.

Always keep in mind they hold all the aces, and we have nothing to gain by questioning them:)
 
Anything less than 3 miles from special use airspace is a deviation for the controller. 1 mile cushion plus the required 3 on 150 mile range that updates 6 times a minute is very small.
 
Solution....stop using VFR flight following! Just kidding, but at least you wouldn't have to hear then tell you that you're in airspace that you really aren't :D
 
Kidding aside, this has raised my awareness that for those few times I'm NOT using FF, I may get the dreaded call when I land. I'm thinking its easier for a bored controller to violate an anonymous radar target than a pilot you're actively talking to.
 
I can't speak for Mohave, but in the MSP class B, there is difference between where the controller's 30 mile ring set is centered vs the gps' (or at least was several years ago, probably still is). The radar (controller's) rings are centered on the radar unit, not surprisingly, which is offset from the MSP airport by perhaps a mile. The airspace as depicted on charts and gps databases is centered on MSP airport. Perhaps this is the case with many airspaces?
 
Keep using FF, it contributes to safe flight if controllers have time to provide the service.

Best way to handle the situation you mention is to respond that your system shows you clear of the airspace but that you will adjust your route to satisfy his system.

That's a lot easier than doing a rug dance at a hearing on the matter.
 
I fly from under the Orlando Class Bravo rings and step up my altitude with the allowed altitude rings. The chart is very specific about where these rings are with alignment to roads in the area. So instead of using the GPS data base I use the roads and lakes but have been called by the tower to decend back out of the Bravo. Seems they are a little slow or out of calibration. By the time I call them back they say I am clear. I did a tower visit once and asked about it and only got a shrugged shoulder.
 
AlexPeterson said:
I can't speak for Mohave, but in the MSP class B, there is difference between where the controller's 30 mile ring set is centered vs the gps'...
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Good point about airspace rings, but in the case of a Restricted area, the boundaries are often highly irregular, and therefore should be defined by thier own coordinates rather than the somewhat ambiguous "centered on" landmark. I wonder if there is information somewhere (available to pilots) that describes the various corners of the airspace in navigation units. One would assume so, considering this is how your GPS "knows" if you are on one side of the line or another.
 
Toobuilder said:
Good point about airspace rings, but in the case of a Restricted area, the boundaries are often highly irregular, and therefore should be defined by thier own coordinates rather than the somewhat ambiguous "centered on" landmark. I wonder if there is information somewhere (available to pilots) that describes the various corners of the airspace in navigation units. One would assume so, considering this is how your GPS "knows" if you are on one side of the line or another.
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The information is available in this document -

http://www.faa.gov/documentLibrary/media/Order/SUA.pdf

..and is defined by lat/long points as you mention.

Here is the R-2501-S area mentioned previously -

R-2501S Bullion Mountains South, CA
Boundaries. Beginning at lat. 34°28'13"N., long. 116°12'23"W.; to lat. 34°27'30"N., long.
116°04'16"W.; to lat. 34°20'09"N., long. 115°59'06"W.; to lat. 34°14'00"N., long.115°57'03"W.;
to lat. 34°14'00"N., long. 116°17'03"W.; to lat. 34°19'30"N., long. 116°20'29"W.; to lat.
34°19'30"N., long. 116°15'50"W.; to lat. 34°24'54"N., long. 116°17'55"W.; to the point of
beginning.
Designated altitudes. Unlimited.
Time of designation. Continuous.
Controlling agency. FAA, Los Angeles ARTCC.
Using agency. Commanding General, Marine Corps Base, Twentynine Palms, CA.

The above is listed to a pretty high accuracy...

A second of latitude is approximately 0.02 miles, or just over 100 feet.

Should be obvious...:)
 
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Special use airspace is drawn onto the controller's overlay using GPS coordinates so it has nothing to do with radar vs airport displacement. Some have already mentioned the IFR separation requirements but as I read it you were VFR so that doesn't apply.

I suspect you were working with a CENTER controller and not a terminal approach control. If that is the case you must keep in mind the CENTER controller uses not just 1 radar site but instead a mosaic of several sites. This is the reason that standard radar separation between IFR aircraft is 5 miles for CENTER guys vs the 3 miles for terminal guys. The center radar is just not as accurate because it is a mosaic.

Not sure what kind of argument you were having but going an extra mile at RV speeds is a much smaller price to pay than even the cost of making a phone call if they wish to speak with you. Of course you can test that theory so long as you report back to us! :D
 
Yes, this is usually Center, but "Approach" has spoken up as well.

And I agree, moving a little to one side is not much of an issue, but my point of discussion is the fact that one's exact position in space is very easy to measure these days, and therefore should be a black and white issue.
 
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