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craig_read

FMC Legs and Routing Issue (bit complicated but)

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Hi.. (PMDG 747 PAX)I don't quite understand what I am doing wrong.. NOW.. correct me if I am wrong here.. BUT.. as I understand the FMC.. the ROUTE pages are to enter route information, and you can do this in a short hand format.. with DIRECT.. VIA.. etc.. and airway names.. right? What happens then.. is that the waypoints associated with you portion of the airway are then automatically collected and placed in the LEGS page.. right?SO.. my question is this.. I'm just messing about really and trying some things out with my new pedals.. I am at EGNJ.. Humberside Airport.. I know it's probably a bit too small but hear me out.... At this airfield there are NO.. SIDs.. none.. there are runways.. and I've selected 03 for departure.. with 03 as arrival into EGNJ as I'm going to do some circuits.. OK.. so.. got the aircraft running.. all performance data entered.. and I got to thinking that I'll try our something with the FMC..Looking at the ND it's all a bit bare and the Legs page has one entry.. RW03 130/85... after that I have the typical --- WELL.. I dug my charts out and thought to myself.. I am sure I can create an interception bearing, put that into the FMC for a nearby waypoint or fix.. The one I chose was UMBEL.. just under 30 miles out from my position... I was thinking.. hmm.. actually.. what I could do.. is create a path from the runway begining to a waypoint derived from UBMEL.. So I thought.. yeah.. 30 miles out ish.. at a almost directly north bearing.. I plugged it into my fix page UMBEL.. RAD 115 and DIST of 14 miles gives me a waypoint more or less DIRECTLY in front of me when I take off.. about 15 miles away in fact.. maybe a bit more.. I thought that might be handy I can climb out to a sensible altitude there.. or I could perhaps intercept a track to UMBEL at perhaps 10 miles out turning left onto it.. ANYWAY.. I am waffling.. The problem is.. I can't enter a waypoint into the LEGS page.. I get INVALID ENTRY... and nothing happens!? Surely this isn't right!?ok.. so this is what I did:1 - Enter EGNJ as origin and dest2 - Enter 03 as runway..3 - Enter TEST as flight number4 - Click activate and exec (still RTE 1 not ACT RTE 1)5 - Press INT PERF set up weights.. fuel.. res.. cost index .. cruz alt..6 - Take off data.. thrust.. etc.. done7 - Legs page.. I see.... RW03 130/85... try to enter UMBEL waypoint.. INVALID ENTRY8 - Go to the ROUTE page.. enter.. DIRECT.. UMBEL.. that goes in.. blue dashed on ND.. activate.. still blue dashed.. on ND.. no change.. nothing in LEGS.. still RTE 1 not ACT RTE 19 - Go to route AGAIN.. enter.. DIRECT UPTON.. on ND.. blue dashed to UMBEL then UPTON.. activate.. and.. turns magenta and RTE 1 becomes ACT RTE 1..10 - back to legs.. no legs.. ACT RTE 1 1/1.... RW03 130/85 the only waypoint.. I enter.. UMBEL.. into the next space.. and it vanishes.. no trace.. It has been entered.. because the ND recognises the change.. by showing the dashed white line.. when I hit EXEC.. nothing.. it vanishes.. but now I have ACT RTE 1 LEGS 1/2... on 2/2 there is nothing just ----11 - I enter UMBEL in here and it inserts the waypoint and a discontinuity..12 - Bridging the discontinuity makes the waypoint dissappear..I am really at a miss.. after messing about for a while.. I can then enter my UMBEL110/15 waypoint and in the LEGS page I have..ACT RTE 1 LEGS 1/1 ..... one entry... RW03 130/85 ACT RET 1 LEGS 1/2 ...... the following... UMBEL110/15... UMBEL... UPTON...But it's not how I wanted it.. What I wanted was.. a waypoint at UMBEL110/15 to then go to UMBEL.. then to UPTON.. and I'd intercept it.. Ideally I wanted a track from the runway to intercept the UMBEL110 radial..Anyone able to help me? I've done my best to explain what I am doing here..CheersCraig


Craig Read, EGLL

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You did provide a lot of explaining.. but not sure what the problem really is. I think the problem is that you have picked a fix out there someplace and you want to build a route around it. This might work if the fix is a part of the airway structure, in which case the FMC gains knowledge of it from the airac data. However, it is not then the FMC looks in the sidstar data and in this case it's not relevant.I recommend playing at a location that has a full set of sids and stars, from there you can pick a departure, connect it to the arrival and get back to your origin. Once you can do that you've covered a lot of ground.


Dan Downs KCRP

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I know how to do it with a SID.. but as far as I can see.. and I might be wrong.. surely you can program intercepts.. etc.. like they are in SID's .. for example the intercept to the path on the WOBUN2F from EGLL... Why can't I programme something like this manually? This airfield has no SID you see.. Aircraft come in and out of it.. surely they do something with their FMCs..CheersCraig


Craig Read, EGLL

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>surely they do something with their FMCs..Why would they have to? I don't know the airport at all, but it's probably a vectored departure. You take off, and ATC tells you where to go, and how to get to your first fix. It'd be just like flying the Atlanta 5 departure at KATL. You have your first fix, and ATC gives you headings to get there.That said, if I'm understanding you correctly, you want to fly straight off of the runway, to intercept the UMBEL R110, correct? If I remember correctly you can't program the FMC to intercept something using the runway. If the runway has an ILS you can use it to create a fix, but without an ILS I believe you are out of luck.What I would do is just fly it manually. Takeoff, maintain runway heading until approaching the UMBEL R110, then turn and intercept it.Someone else can correct my above information if it's incorrect. You might also try the VATSIM-UK forum. I'm sure someone there would know the departure procedures for this airport.


Mike Roth

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Mike,It's just curiousity really.. I would like to learn more about programming the FMC.. I mean I know how to do all this manually but I was wondering if there is a way you could program all this yourself for the automatics to do the workd for you.. and it seems like it might not be able to.. which is good in a way because it means I can't do it because it can't do it.. not because my knowledge is short.. I mean... If I had to do it.. I'd put the fix in.. start the flight plan at UMBEL on the Route pages.. and set the fix with the radial I want.. and perhaps program the VOR in on that heading and fly it manually with a sensible altitude target for UMBEL.. But I'd really like to know if there is a way you can actually key in interceptions etc... they exist in a lot of SIDs.. so surely we can add them manually?Craig


Craig Read, EGLL

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Craig,This happened to me today! I was testing out a failure of the MCP/Autopilot system to capture a LOC on an ILS approach to runway 30R into Dubai (OMDB).The problem here was caused by an update to the latest AIRAC 0703 which presented new data about this runway into the 747 FMC. ILS runway 30R identified now as a DME only approach and the aircraft flew right through the localiser! Solved by the way - using the default ILS for the runway found in the scenery and entering it into the NAVRAD page to over ride the FMC data, allowed a normal full ILS landing.Anyhow .... I did the same to test this problem. Set both departure point and destination the same (OMDB) and found that I could not place any waypoints, custom or otherwise, into either the RTE page or the LEGS page at any point in the FMC setup. In the end, I went with a normal TOGA takeoff to 5000 feet on HDG SEL mode on the MCP and made all turns using the autopilot in selected mode. Once airborne, I found I could add a VOR radial but little else. The usual bits like the VREF speed could be inserted ok and actually flying a circuit in the bird is fine providing you know what your doing (its not a Cessna!) and keep your fuel load nice and low and in my problem example, I found that by changing the ILS frequency in the NAVRAD page from the FMC's own 110.90/300 to my default frequency (can be seen using FSNAV) of 109.50/300, I got a full localiser/glideslope ILS and the aircraft made a normal roll over onto the centreline.It could be just the limitations of the FMC generally or those found in the PMDG version - seems always to happen if you select both the departure and destination the same into the FMC!Cheers,Lee


Lee James
Senior Captain
Events Manager

British Airways Virtual
Pilot of SPEEDBIRD 9 DELTA VICTOR (BAW9DV)

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Craig,Basically all you want to do is sort of a free flight to test your new pedals, right? If so, there is a crude way you can simply fly the 744 without a programmed FMC. If you simply hit the flap configuration override button, you won't get an alarm when you throttle up for takeoff. When you're in the air, you can simply use the ALT and SPD functions of the autopilot, or just hand fly the aircraft. I learned this little trick when I wanted to test the FPS using a scenery I got with the 744. I didn't really want to file a whole plan; just taxi out, takeoff, turn around, and land.Ryan GamurotLucky to live Hawai'ihttp://www.virtualpilots.org/signatures/vpa296.png


Ryan Gamurot
 

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Cheers for the replies..I'm not really after flying the bird manually.. I know I can do that and I have done.. What this thread is about really.. is that often in SIDs.. you'll see the runway.. then an intercept track which you grab shortly after take off.. and then continue the SID till you go on your merry way..Is it possible to enter these intercepts.. manually? If so I'd like to know.. And the other.. why can't I add waypoints AT ALL.. to the LEGS page in this instance? It doesn't make sense to me.. surely you can populate the legs page whenever you want with whatever you want.. I have RW03.. then blank.. then whenever I enter any waypoints.. I get.. INVALID ENTRY.. which has got to be wrong!? Surely.. I can enter waypoints.. I have to faff about with the ROUTE page.. in this manner.. and even then it doesn't seem to work properly..This particular airport has no SIDs.. I don't see any logical reason why I can't program my own (and I don't mean add it to the SID database.. I mean manually in the FMC during pre-flight).. and that's really what I'm trying to do.. and for whatever reason.. I can't.. On PS1.3A the behaviour is different.. (albeit at Heathrow as EGNJ is not in the database).. I select the aiport.. as DEST and ORIGIN.. I set the runway to 27L (on ARR/DEP.. it is depitcted as 27L nothing else is selected).. It gives me the option to ACTIVATE.. I do.. and instantly RTE 1 becomes ACT RTE 1.. this doesn't happen in PMDG why not? Which is right? I then go to the legs page.. which is empty.. and hey presto.. I can enter waypoints.. something is a miss here with one of these models.. I mean I know it's a simulator and I can't expect perfection.. that's fine.. etc.. and I know what would normally happen.. the 747 wouldn't use this airport.. take off maually and intercept the route.. etc etc.. But I am already very experienced with the FMC and don't understand this behaviour.. I would expect to be able to enter.. EGNJ as the origin and destination.. and be free to enter waypoints as I see fit on the LEGS page.. right away.. On PS1.3A everything seems to work as I expect it to... Although I think the construction of the SIDs are less complex than those in PMDG.. for example they are without the INTERCEPT courses in them.. the WOBUN departures intercept a radial which is on the ND.. and magenta.. there is no connection between the runway line and this path.. you climb.. LNAV then turns as you get a low cross track error this intercept line.. just like if you were to setup any intercept radial in your flight..So can anyone shed some light?RegardsCraig


Craig Read, EGLL

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Craig,I can do all of the above ..... I enter waypoints and create approaches (ARCS?) all the time.I just cannot do it when the departure airport set into the RTE page is the same as the destination airport.This is usually what causes the problem. Not sure if it is reality or not yet....cheers,Lee


Lee James
Senior Captain
Events Manager

British Airways Virtual
Pilot of SPEEDBIRD 9 DELTA VICTOR (BAW9DV)

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Craig,If you know what course you're intercepting and what fix/VOR etc it's to or from, you can very easily set up an LNAV intercept. Take the waypoint and line select it to the top of the LEGS page as if you were doing a direct-to. Now look down at LSK 6L and you'll see a prompt called INTC CRS - enter the course heading into that box and hit EXEC. You'll see a magenta line drawn from the waypoint to infinity along that course. Just fly toward it with LNAV armed and the plane will intercept.


Ryan Maziarz
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For fastest support, please submit a ticket at http://support.precisionmanuals.com

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I don't think Ryan (Tabs) has understood what I am looking for.. I know how to intercept a track in the air using the intercept course funtion.. you put the waypoint to the top.. and set the radial no problem there.. That's not my query... My first query is this... IF you're sat on the ground with no engines running at all.. etc.. pre-flight at heathrow.. and you enter a SID say WOBUN2F.. you'll notice.. there is an entry.. INTC in the legs page.. HOW.. can I create one of these entries myself using the FMC while I am sat at the gate, if at all? That was one query..The other is.. when using the same airport as dest origin and there aren't any SIDs to use.... I can't enter legs into the legs page at all.. and when activate the route.. with the same origin and destination.. RTE 1.. stays as RTE 1 in the FMC title.. instead of ACT RTE 1... and that has to be wrong.. surely.. With PS1.3A.. I have no problem doing doing this.. it functions as I expect it to.. is this a bug or is it intended?CheersCraig


Craig Read, EGLL

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When you first enter your departure and destination airports, you then have to hit next page to go to the page were you enter your route, the LEGS page is were you can change then once your route is activated, someone correct me if im wrong on that Chris


Chris McKenna

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Chris..I know the FMC on the 747-400 very well... I'm fairly well versed in the specifics.. I am not sure what you mean.. but the ROUTE pages.. are for convenience to enter routes short hand.. where you can enter entry points to airways and once completed.. the legs page is populated with all the waypoints on route.. This is not the issue.. and what you're saying isn't the case.. You can enter LEGS waypoints at any time during the process... In theory.. (and in PS1.3A I can).. you can enter waypoints into the legs page immediately...I appreciate your response.. and I know you're trying to help me.. but I would ask you to please make the assumption I am extremely well versed in the FMC operation.. for example.. I know about x-track errors in the FMC.. maintenance pages for the changing of drag co-efficients.. etc etc... how to set up interception courses during flight.. holds and more.. Some of these aren't even included in the PMDG model.. (maintenance pages).. I understand the proceedure.. But my problem I believe is a bug.. not a function of the FMC..Thanks..Craig


Craig Read, EGLL

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Craig,Psuedo waypoints like (INTC) and the other ones like track after reaching a certain altitude, track after a certain DME, etc are not creatable by the pilot from the FMC. It's that way in the real plane too, those have to be in the database already.The only custom waypoints that can be entered by the pilot are the ones listed in the manual...


Ryan Maziarz
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For fastest support, please submit a ticket at http://support.precisionmanuals.com

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Is this what you wanted to do, just curious myself now, probably a long day at work.This is what I used ( UMBEL110/15 to then go to UMBEL.. then to UPTON )Cause i tried it the way you described it and had some success with it, just the on fix that never showed up in the LEGS page, the RWY oneOff the ND is UPTONhttp://forums.avsim.net/user_files/169112.jpgChris


Chris McKenna

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