who4ever

Approaches: ATC, GPS and Charts

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When I am flying an IFR flight plan, following ATC commands, when I am nearing my destination and ATC starts vectoring me in, is ATC actually vectoring me according to a published Approach that I can use the chart and GPS as an aid, or is it just random commands that may or may not be the same each time I fly the same flight plan?  If ATC is actually vectoring me according to a published Approach, how can I tell which one it is?
Thanks, Dave

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No, ATC vectors you at a 90 degree angle and then to an angle under 30 degrees depending whether it is an ILS or visual approach. I always let my flight planning software make a plan from the airport center up to the destinations airport center, this way you can always use it, no matter which RWY for start and landing.

Herman

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Hi Dave,

ATC will be vectoring you for a particular approach (which they should state right at the beginning -- "turn left heading xxx, vectoring for the ILS runway 27R"). Whilst you are being vectored, ATC assume responsibility for your navigation and terrain clearance, but you obviously should as a matter of good common sense and airmanship maintain good awareness of your position (particularly as whatever the law may say about ATC being responsible for terrain clearance, it's not them that will be splattered across the mountain if they screw up...)

However, you will normally be vectored for sequencing reasons towards the final approach course (for an ILS/VOR approach etc) or final approach fix (for an RNAV or similar approach). The tracks you follow will probably not follow any particular chart -- the controller has a "radar manoeuvring area" (RMA) that they have to keep you within and there will normally be a standard-ish pattern that most traffic will be vectored to follow but within the RMA really anything goes in order to make the plan/sequence work.

However, as mentioned, you should keep an awareness of your position in relation to the final approach track in order to manage your descent, speed etc appropriately.

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That would probably depend upon whether you were using the default FS ATC, or a payware add-on ATC program such as Pro ATC X, Radar Contact or some such.

Default FS ATC will typically give you some vectors to fly which will set you up for an approach to the best runway for the wind conditions, typically they're going to try and have you finish up flying at about 30 degrees or less than the runway's magnetic heading, so that you can either intercept the ILS, or fly a visual approach. Whilst that can sometimes happen in real life, it is far more likely that in real life ATC would contact you when you are on your descent and tell you to expect a particular runway, at which point you can start setting up course selections and radio frequencies for the ILS of that runway. Then they would likely give you more detailed information soon after, telling you a published approach procedure, and at that point, if you were flying a modern airliner, you'd select that approach procedure on your aircraft flight management computer, if you had an older aircraft with no FMC, you'd get the plate (chart) out for that approach procedure (that's among the things pilots have in those big briefcases you see them carrying) and clip the paper approach plate to the yoke, so that you could fly it by referencing it. In fact, you'd probably do that with the plate anyway, even with the approach entered into the FMC if you had one, since it is conceivable that your FMC could malfunction, but n any case, with the procdure in the FMC, the published approach track will of course display on your primary flight display too. Very modern fancy airliners such as the B787 have 'electronic flight bag' displays (a bit like an ipad), which show the approach plate for you instead of you having to clip a paper one to your yoke.

So, typically, you'd get something like this from ATC: 'Flight XYZ123, turn left heading 123, decend and maintain 5,000 feet, expect runway 23L via the Narnia approach.' At which point you'd input Runway 23L and select the Narnia standard arrival procedure for that runway (aka the STAR) into your FMC, and that procedure would then be added to the end of your IFR route so that the autopilot could fly it, or you could fly it manually by referencing the route track on the PFD.

Theoretically, you can do all that STAR malarkey with the default route planner in FS if you really want to go to the trouble, although it is a bit of a faff to pull that off. What you can do if you wish to try that, is open up your IFR flight plan map on the default flight planner in FS, then drag the IFR route line to any additional waypoints you like, so that could include customised waypoints which you could determine by referencing an approach procedure plate. Doing that would then make the published approach become part of your default FS flight plan and so the default ATC would of course then try to get you to fly that course, although the default ATC would not be referring to it as a STAR, it would merely treat it as part of your planned flight route, so it's not completely realstic of course, but it is at least a way to have a procedure display on the default FS GPS and your PFD and have the default FS ATC sort of use a published approach procedure. Having said all that, it's a hell of a lot easier to have a better ATC program than the default FS one and an FMC on your aeroplane to do all that stuff with less effort on your part.

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Thank you all for your time.  So just to clarify, when I am using the default FS flight planner and default FS ATC, I will not be informed by 
ATC which Approach they are vectoring me to, only the runway, right?

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11 minutes ago, who4ever said:

Thank you all for your time.  So just to clarify, when I am using the default FS flight planner and default FS ATC, I will not be informed by 
ATC which Approach they are vectoring me to, only the runway, right?

Normally ATC will give you either a visual approach, GPS approach, or ILS approach to a runway depending on conditions.  I may have gotten an RNAV approach once, but I then changed it to a Visual.

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16 minutes ago, who4ever said:

Thank you all for your time.  So just to clarify, when I am using the default FS flight planner and default FS ATC, I will not be informed by 
ATC which Approach they are vectoring me to, only the runway, right?

Yup, but with modern ATC systems sometimes vectoring aircraft in like that anyway because of the advent of GPS, it's not completely unrealistic.

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Has anyone ever succeeded in changing the ATC-assigned approach or runway to another one stored in the GPS database for the particular airport?

There is an ATC submenu for that, but the last time I tried to get another runway, I got told to sidestep back to the original one.

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The default action of FS ATC is to give you a vectors-to-final.  The optional action is to use the ATC menu to request an approach and transition.  In that case FS ATC vectors you to the transition entry (for ILS approach has to be a transition based on VOR).  You have to make requests for 1 runway 2 approach and 3 transition.  If you don't request a runway you will get the "sidestep" (if your requested approach is not to the ATC-prefered runway).

 

scott s.

.

 

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38 minutes ago, scott967 said:

If you don't request a runway you will get the "sidestep" (if your requested approach is not to the ATC-prefered runway

That's right and this is also the way to get a circling approach if you want. For example if you want to land on runway 9, but use the ILS approach for runway 27, you can use the ATC menu to request that and it will clear you to circle to land on runway 9. This can be a good way to use the ILS minimums to get a visual on the runway while landing on a different runway that doesn't have an ILS.

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For the first time (ever?), I really tried to fly a non-vectored approach with default ATC. Requested a GPS approach with a suitable transition and ATC granted permission and gave me altitude advisories until the initial approach fix. Pretty cool!

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3 hours ago, Bjoern said:

For the first time (ever?), I really tried to fly a non-vectored approach with default ATC. Requested a GPS approach with a suitable transition and ATC granted permission and gave me altitude advisories until the initial approach fix. Pretty cool!

I used to do this, but more often than not, it leaves you too high to meet altitude restrictions.  Also, applying the magdec/navdata upgrade to the sim ruins the approaches.  You won't even have the choice to pick a GPS/RNAV waypoint anymore.  It's annoying.  I decided I prefer to have runways and navdata that matches my Navigrach AIRAC for complex add ons, mainly because it puts you too high on approach more often than not.

Last time I tried it, I was heading into KPSP with default magdec/navdata.  I was in the RealAir duke with GTN750.  I think I was heading to the TEVUC waypoint.  Request grated but ATC wouldn't allow me to descend below 7000 feet until I was almost over TEVUC.  Then it was a dive to meet constraints.  Try doing that in a Boeing....

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I think you will find the altitudes in the FSX approaches were correct as of the date the data was dumped from an actual approach database.   In  particular the IAF altitude is correct per the charts.  If you update your charts, or change the magdec  without updating the FSX fixes or approaches, then of course they won't match.

 

scott s.

.

 

 

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17 hours ago, Orlaam said:

I used to do this, but more often than not, it leaves you too high to meet altitude restrictions.  Also, applying the magdec/navdata upgrade to the sim ruins the approaches.  You won't even have the choice to pick a GPS/RNAV waypoint anymore.  It's annoying.  I decided I prefer to have runways and navdata that matches my Navigrach AIRAC for complex add ons, mainly because it puts you too high on approach more often than not.

Last time I tried it, I was heading into KPSP with default magdec/navdata.  I was in the RealAir duke with GTN750.  I think I was heading to the TEVUC waypoint.  Request grated but ATC wouldn't allow me to descend below 7000 feet until I was almost over TEVUC.  Then it was a dive to meet constraints.  Try doing that in a Boeing....

Yep, altitude was a bit problematic at the IAF, but I tried to comply with the values on the plate for all further fixes.

Since I don't even try to stay current with my sim environment, my navdata and magvar is still default and I don't fly airplanes requiring Navigraph data, so compatibility is not much of an issue for me.

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20 hours ago, scott967 said:

I think you will find the altitudes in the FSX approaches were correct as of the date the data was dumped from an actual approach database.   In  particular the IAF altitude is correct per the charts.  If you update your charts, or change the magdec  without updating the FSX fixes or approaches, then of course they won't match.

 

scott s

Yes they match because I have all the older charts on paper.  The problem, despite FSX having the correct altitudes in the approach profiles, is that you aren't allowed to descend on time per your distance and speed.  If you're going 210 knots at 10,000 feet and have 7 miles to get to the IAF at an altitude of 5,000 then it ain't happening.  Of course you could dive at 2500 FPM and bust the speed restriction, but then you'll never slow in time to configure properly for landing.  It's a problem more often than not with default ATC, henceforth the reason I stopped using it for IFR.

Perhaps those descent profiles work if you are in a Cessna going 120 knots, but not much else.

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9 hours ago, Orlaam said:

Yes they match because I have all the older charts on paper.  The problem, despite FSX having the correct altitudes in the approach profiles, is that you aren't allowed to descend on time per your distance and speed.  If you're going 210 knots at 10,000 feet and have 7 miles to get to the IAF at an altitude of 5,000 then it ain't happening.  Of course you could dive at 2500 FPM and bust the speed restriction, but then you'll never slow in time to configure properly for landing.  It's a problem more often than not with default ATC, henceforth the reason I stopped using it for IFR.

Perhaps those descent profiles work if you are in a Cessna going 120 knots, but not much else.

I never had troubles with that and I fly the iFly737 and the Wilco Airbusses vol1 all the time on managed descend but default planes aren't very realistic with the V/S default at 1800ft/min

Herman

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On 3/22/2017 at 8:15 PM, scott967 said:

The default action of FS ATC is to give you a vectors-to-final.  The optional action is to use the ATC menu to request an approach and transition.  In that case FS ATC vectors you to the transition entry (for ILS approach has to be a transition based on VOR).  You have to make requests for 1 runway 2 approach and 3 transition.  If you don't request a runway you will get the "sidestep" (if your requested approach is not to the ATC-prefered runway).

 

scott s.

.

 

Nice to see someone else who understands FS ATC. What I do apart from writing new approaches every time I fly (update) is make the transition altitude (IAF) the glideslope interception altitude which not only makes  FSATC do a far better job with my descent rate but also makes sense of the phrase "descend and hold xxxxxft until established" (xxxx being the GS interception height) 

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On 3/26/2017 at 0:32 AM, electricman said:

I never had troubles with that and I fly the iFly737 and the Wilco Airbusses vol1 all the time on managed descend but default planes aren't very realistic with the V/S default at 1800ft/min

Herman

I haven't truly flown a default MS plane in 15 years.  It's been Dreamfleet, PSS, Level-D, PMDG, and others all along.  I used to use the ATC approaches in FS9 with the myriad add ons I had from PMDG, Level-D, Dreamfleet, Digital Aviation, and I think maybe 50% of the time I could make the altitude at IAF.  If you are just following ATC for ILS vectors then fine, but to choose an actual approach with an IAF and expect ATC to let you meet that restriction?  No way.

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I didn't talk about a chosen approach but the assigned approach, if you want to request a different approach because you can't get to the altitude restriction in time then that strikes me as odd, in my opinion that is a missed approach and a go around.

Herman

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