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EFIS APP Mode

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Would somebody mind giving a description of how the APP mode on the EFIS works in the ND for the 777.  I have found one video that appears to explain EFIS and using the APP mode in the ND, but it's in German.  I have not been able to really find any other source that goes into detail on it.  I'm wanting to understand it better so I can use it for more situational awareness.   Any help would be greatly appreciated, Crash.

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The APP mode display is simply a course deviation indicator (CDI). It displays course and LOC/VOR course deviation and glideslope deviation. There's nothing special about it, and the same VOR/LOC/GS information is available on the PFD.

 

I rarely use it and leave the ND in MAP preferring to use the PFD as primary for ILS approach, and the MAP mode gives me a better situational awareness with IF and FAF mapped on the display.


Dan Downs KCRP

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I'm trying to learn how to let the ATC guide me in approach instead of assuming that the runway I entered in the FMC will be available.  Obviously it's much more realistic as this can change by the time you reach your destination airport.  However not having any real training( i'm not a real pilot), the challenge for me is situation awareness when on approach, compared to just following the FLP all the way to the runway.  FSX default ATC is not the best, but it is as real as I can make it unless I used I live ATC program which at this time I'm not interested in.  So far the best way I have is using both the APP mode in conjunction with the airport fix (/35, /20, /10) for awareness and it's a great help.  I'm not used to using the APP mode so I wanted to make sure I understood it as much as possible, so thanks much for the response.  If anyone else has some additional advice it would be appreciated.  Otherwise, I'm considering this case closed.  Thanks again, Crashbar.

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If anyone else has some additional advice it would be appreciated.

 

See Page 5.13 of the FCTM for detailed guidance on when to switch page from the MAP to the APP display. Essentialy when the ILS is tuned and identified, you are on an intercept course with LOC and G/S indications and clearance to approach has been received.

 

Obviously if you don't switch to the APP mode (and like Dan I rarely do) that's up to you. Procedurally Boeing recommend you use it. Airline SOPs may differ.


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So far the best way I have is using both the APP mode in conjunction with the airport fix (/35, /20, /10) for awareness and it's a great help. I'm not used to using the APP mode so I wanted to make sure I understood it as much as possible, so thanks much for the response. If anyone else has some additional advice it would be appreciated.

 

Hi, Dominick,

 

I'm not sure if you mean the EFIS APPR mode or the MCP (Autopilot) Approach mode.  I think you are better off leaving the EFIS in MAP mode as Dan and Kevin suggested.  Then you can see where you are in relation to the airport and the specific runway you are aiming for.   You can still use the two moving dots on the PFD to see how you are lining up w/ the localizer and glideslope. 

 

If ATC changes your runway, you need to change it by going to the DEP/APPR page of the CDU, selecting Approach and choosing the new runway (By doing this, the FMC will also tune the new ILS frequency if available).  You may or may not be able to see the new runway on the ND Map depending upon where you are, but if ATC vectors you correctly, eventually you will see that you are getting near to lining up w/ your final approach course (usually lined up w/ the runway).  That's a good time to click onn APPR on the MCP, so that you will follow the localizer and glideslope if available.

 

Mike


 

                    bUmq4nJ.jpg?2

 

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Hi, Dominick,

 

I'm not sure if you mean the EFIS APPR mode or the MCP (Autopilot) Approach mode. I think you are better off leaving the EFIS in MAP mode as Dan and Kevin suggested. Then you can see where you are in relation to the airport and the specific runway you are aiming for. You can still use the two moving dots on the PFD to see how you are lining up w/ the localizer and glideslope.

 

If ATC changes your runway, you need to change it by going to the DEP/APPR page of the CDU, selecting Approach and choosing the new runway (By doing this, the FMC will also tune the new ILS frequency if available). You may or may not be able to see the new runway on the ND Map depending upon where you are, but if ATC vectors you correctly, eventually you will see that you are getting near to lining up w/ your final approach course (usually lined up w/ the runway). That's a good time to click onn APPR on the MCP, so that you will follow the localizer and glideslope if available.

 

Mike

Mike,

 

I didn't say he should stay in MAP mode. I said it wouldn't matter if he did for convenience. If he wants to operate correctly then he should switch to APP mode once established on the ILS.

 

Kevin


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Hi Mike, I was talking about the EFIS APP mode.  When I enter the flight plan into the CDU before flight, I enter in the runway that ATC clears me on to take off from, and on destination I go to LEGS page and enter the code for the airport (ex. KIAD) and then enter 185(speed)/*ALT (altitude of destination airport) into the line to the right of the code.

Then when I get close to the airport I wait for ATC clearance to the selected runway, and then I enter that runway's LOC frequency/course into the NAV RAD page of the CDU.

 

Your recommendation is to go to DEP/APPR page of the CDU when cleared for landing runway, and enter that runway.  If I do this, should I even bother to enter in the destination airport code when I enter in the initial flight plan, or do I leave it blank until I get the landing clearance to my destination?  

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Dominick, the 777 automatically selects LOC frequency and course. No need for you to enter that manually.

 

Mike suggested this only if ATC changes your approach, in which case you select the new approach not the runway. Selecting a runway is a set up for a visual approach. The destination code is necessary but arrival and approach are optional.  Most flights, these are known during preflight. They might change but for the purposes of simming it is okay to select early. There are situations where you don't know the approach until you contact approach control, just select the destination and arrival for the most likely path at preflight.


Dan Downs KCRP

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I didn't say he should stay in MAP mode. I said it wouldn't matter if he did for convenience. If he wants to operate correctly then he should switch to APP mode once established on the ILS.

 

Kevin, sorry that I misunderstood your comment.  I am curious now to know what typical RW practice is.

 

 

 

on destination I go to LEGS page and enter the code for the airport (ex. KIAD) and then enter 185(speed)/*ALT (altitude of destination airport) into the line to the right of the code.

 

Then when I get close to the airport I wait for ATC clearance to the selected runway, and then I enter that runway's LOC frequency/course into the NAV RAD page of the CDU.

 

Your recommendation is to go to DEP/APPR page of the CDU when cleared for landing runway, and enter that runway. If I do this, should I even bother to enter in the destination airport code when I enter in the initial flight plan, or do I leave it blank until I get the landing clearance to my destination?

 

Hi, Dominick,

 

If I understand you correctly, you are entering the destination airport as a waypoint on the legs page, presumably at the end of the route.  This is unnecessary -- the destination is already known to the FMC because you entered it at the top right on the main flight plan page.  It could also cause route problems.

 

If you are expecting an ILS approach, go to the DEP/ARR page, then choose the ARR for your destination airport.  Then choose the entry that starts w/ "ILS" for the runway you have been given by ATC.  That will set the waypoints for the approach to the runway and autotune the frequency and course for that runway and its ILS.  You will be able to see the approach waypoints on your ND in MAP mode.  (A good  reason NOT to make the destination airport a waypoint on the legs page is that the runway approach might be inserted after the airport, which would mean you would fly to the airport and then have to turn around 180o to fly to the beginning of the approach and then turn around again to begin the approach -- take a look on the ND MAP page and see what the path looks like).

 

As Dan said, you want an Approach for your chosen runway -- if you just select the runway number without any approach I believe you won't get any lead-in waypoints.

 

There are also arrivals available at most airports for the various runways but that is beyond this thread's topic, as are the various other types of approaches.

 

I have the feeling that you have not done any of the tutorials.  Even if you have, it would be good to repeat at least the first one (the second one, by Kyle Rogers, is available on this forum but doesn't come w/ the 777).

 

Mike


 

                    bUmq4nJ.jpg?2

 

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Kevin, sorry that I misunderstood your comment. I am curious now to know what typical RW practice is.

No problem Mike, I just wanted to clarify it. The best source of info we all have is the FCTM. See the page I referenced earlier, for example. Only a real world Boeing pilot could give the practical point of view.

 

I've always assumed the reason to switch to APP mode is to give the pilot flying complete focus on the ILS approach by presenting a decluttered EHSI. The pilot monitoring will usually keep the MAP view displayed for additional situational awareness. Simmers are in effect both PF and PM so using MAP throughout is a reasonable compromise.


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A side question:  When I select an RNAV approach, the FMC doesn't autotune the ILS/Localizer frequency for that runway.  I sort of understand the logic behind this, but I would think in RW the pilot would likely fly RNAV until he picks up the Loc and GS if available and then switch to MCP APPR mode, or at least use loc and/or GS as backup guides for what is essentially a visual final approach.

 

So why doesn't the FMC autotune?  Seems to me it just creates an additional hassle for the pilots.

 

On the MAP/APPR question, I sometimes set the fictional copilot's ND to MAP and my (i.e. the Captain's) ND to APP, but the problem with this is that if I need to go around I don't have an easy view of the missed approach course.  So I'm tending more to just leaving the ND in MAP and using the little pips on the PFD for LOC/GS.

 

Mike


 

                    bUmq4nJ.jpg?2

 

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I'm happy to be corrected, but I can't imagine that a RW pilot would select a RNAV approach in the FMC if he actually doesn't want to fly the RNAV approach nor use the RNAV approach as reference for a visual approach. Why would he select an RNAV approach if he wants to use the localizer and/or ILS glideslope as a reference?


Marc ter Heide

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A side question:  When I select an RNAV approach, the FMC doesn't autotune the ILS/Localizer frequency for that runway.  I sort of understand the logic behind this, but I would think in RW the pilot would likely fly RNAV until he picks up the Loc and GS if available and then switch to MCP APPR mode, or at least use loc and/or GS as backup guides for what is essentially a visual final approach.

 

So why doesn't the FMC autotune?  Seems to me it just creates an additional hassle for the pilots.

 

On the MAP/APPR question, I sometimes set the fictional copilot's ND to MAP and my (i.e. the Captain's) ND to APP, but the problem with this is that if I need to go around I don't have an easy view of the missed approach course.  So I'm tending more to just leaving the ND in MAP and using the little pips on the PFD for LOC/GS.

 

There's a little overcomplicating going on here, in addition to a little confusion, it seems.

 

It doesn't autotune because an RNAV approach is a wholly different approach. If you're flying the RNAV, you don't need the ILS or LOC. The technologies are independent (the fact that RNAV approaches exist to runways without an ILS is an indicator of this). Having both up could lead you astray if there are minor differences between the two approaches. This usually doesn't happen (in this case, the approach is referred to as an "overlay"), but in some cases, it can, which could cause a problem.

 

The SOIA operation at SFO would be an example of this:

When the weather is low, despite the two sides (28L and 28R) having ILS, you cannot operate the approaches independently because the runways are so closely spaced. That means that your arrival rates plummet because you run into spacing issues (this is the reason why DEN's runway pairs are so far apart - the approaches can be run independently). To solve this, the right side goes into an RNAV RNP (where possible, as not all aircraft are equipped for this) approach that creates an offset approach path far enough out to be considered an independent parallel approach. Once the aircraft breaks through the clouds, the crew calls the other aircraft (on the ILS) in sight, and "sidesteps" visually off of the old fake approach course and over to Runway 28R (visually - the RNP part of this allows for the lower mins). If the crew had the ILS information up, the conflicting cues could be misleading or confusing, and if followed, could really, really mess up the whole SOIA operation.

 

Here's a link to a PDF with examples. The SFO example is about half way through, though it starts with the N90 example that I've referenced a few times here in the forum (usually with the line "put JFK on the 13s and watch N90 go down the tube").

 

Why fly an approach that gets me to the airport, but then switch from it to some other method of an instrument approach that does the same thing? If the ILS was required for some reason, then that's what should have been flown from the outset.

I'm happy to be corrected, but I can't imagine that a RW pilot would select a RNAV approach in the FMC if he actually doesn't want to fly the RNAV approach nor use the RNAV approach as reference for a visual approach. Why would he select an RNAV approach if he wants to use the localizer and/or ILS glideslope as a reference?

 

I can't think of a case in which I would under any normal circumstance.


Kyle Rodgers

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For best situational awareness, use MAP mode.

It draws you a picture of where you are in relation to where you want to go.

Much easier to interpret than NDB/VOR needles and ILS course deviation pointers.

 

APP mode basically puts you back into a Cessna like display....also called raw data mode.

(you can switch between full rose (even more Cessna look) and expanded rose by presses on the CTR (center) switch inside the same switch you use to select MAP/APP etc)

 

I have never used the APP mode in real world as all available info is also available on ND in MAP MODE+PFD.

Our airline recommends both pilots use MAP mode.

 

In my opinion the APP mode is to be used only in case of MAP mode failures such as map shifts (GPS failures). In that case to not get situationally confused by a wrong map drawing I would switch to APP mode.

 

I also use APP mode for fun to test if I can still navigate/fly approaches by means of raw data.


Rob Robson

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As mentioned already and just to confirm:

 

If ATIS reports ILS in use - then select the ILS approach from the FMC.

If ATIS reports Rnav in use - then select the appropriate Rnav approach from the FMC.

 

In FSX....do what you like to practice today :-)

 

But there is no such thing as selecting an ILS approach if you are going to fly an Rnav approach or vice versa.

 

Kyle mentioned a great example of why an Rnav approach would be used rather than an ILS approach.

Similar, when going into JFK on runway 22L you are 90% of the time cleared for a VOR22L approach although the runway is equipped with ILS.

Also for separation reasons as Kyle explained me in the past (separation from La Guardia traffic).

That VOR22L is not an Rnav approach....it is a VOR approach and thus you have to select the VOR22L from the FMC.

But you can fly it just the same with Lnav and Vnav or Lnav and FPA mode.

 

An other reason for an Rnav approach is that the ILS might be inoperative or on maintenance.

 

In practice though, generally when a runway is equipped with an ILS approach, you usually are cleared for an ILS approach.

 

Once you are cleared for an RNAV approach the ILS deviation pointers are of no use.

You dont want them at that point.

As Kyle said flying according to the ILS deviation pointers while cleared for an RNAV approach could really create big problems.

The ILS and RNAV approach can have a different inbound track and glide path angle!

The missed apprach for both approaches can be completely different as well!

 

If you want to fly an Rnav/Vnav approach, then make sure the altitudes at approach waypoints in the legs page are the same as on your approach plate!

 

Once you select an Rnav approach from the database you will (at some point) get a course and glide path deviation indicator on the PDF just as you would normally get for an ILS. (pink diamonds on a vertical and horizontal scale on the PDF).

Just note that on top left of the PDF, where you would normally see the ILS frequency and course, you will see Lnav/Vnav indicated.

Meaning that the pink course and glide path deviation indicators are giving you deviation from the programmed Rnav course and Vnav path!

You can try to follow this manually (unless it is an RNP RNAV approach) or with AP engaged.

 

Also note that while en route/arrival, you will also see Lnav/Vnav on top of the PDF.

Even if you have selected an ILS approach into destination, this Lnav/Vnav indication stays there and it tells you that the pink diamonds are giving info about deviation from your planned Lnav/Vnav course and path.

Once you pas a certain point (I think the initial approach fix) then Lnav/Vnav (top left in PFD) will change to ILS frequency(or ident) and inbound course.

And THEN the pink deviation pointers are true ILS deviation pointers.

 

Very confusing all.....especially not confusing AP/FD modes (what the AP is doing) with PFD deviation indications is confusing and takes getting used to!


Rob Robson

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