737NG FMC Question
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737NG FMC Question
Quick FMC question, apologies if this has been asked before.
We have an airport which is a noise requirement to go straight ahead on runway track until above 3000ft before turning to the first flightplan waypoint. Is there a way I can create the (3000) on the left column manually so it turns when at 3000 or above? Obviously I can create it with a distance from the airport code and 3000A on the right, but the distance is variable, the only requirement is to be above 3000. Another location has more complex noise - Straight ahead (rwy track) until 700ft, then track 057 until 3000 - again, is there a way to make the box do this in LNAV or is heading select the only option?
Is using the airport identifier and the runway track in the FMC the most accurate way to create a virtual LNAV centreline?
Also, is there a simple way to clear out all the user created waypoints to avoid the list of waypoints that are hundreds of miles away from the one you need when creating a base leg etc?
Many thanks in advance
We have an airport which is a noise requirement to go straight ahead on runway track until above 3000ft before turning to the first flightplan waypoint. Is there a way I can create the (3000) on the left column manually so it turns when at 3000 or above? Obviously I can create it with a distance from the airport code and 3000A on the right, but the distance is variable, the only requirement is to be above 3000. Another location has more complex noise - Straight ahead (rwy track) until 700ft, then track 057 until 3000 - again, is there a way to make the box do this in LNAV or is heading select the only option?
Is using the airport identifier and the runway track in the FMC the most accurate way to create a virtual LNAV centreline?
Also, is there a simple way to clear out all the user created waypoints to avoid the list of waypoints that are hundreds of miles away from the one you need when creating a base leg etc?
Many thanks in advance
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ballyboley,
The first two situations you ask about require what are called 'conditional waypoints' & unfortunately can't be entered by the flight crew. They can only be entered into the database as SIDs or STARs by the powers that be.
Regarding the third question, you should be able to enter the runway threshold as a waypiont in either the legs page or the fix page, eg. RW19 (it might be RWY19 - my memory is getting a little dim!). When you type this in you will get a number of waypoints to chose from, particularly if there are a number of airports in with the same runway direction in the area, so be carefull to get the correct one. They are listed in the order of closest one first. If you are close to the airport, the correct one should be at the top. Then, on the legs page you then put this point to the top of the page (if you didn't enter it there in the first place) & type the inbound track into the bottom right corner. On the fix page just put the reciprocal track in as a radial.
Sorry, I don't know the answer to your last question, but if I remember rightly, all the user defined waypoints are cleared after landing - not sure though!
The first two situations you ask about require what are called 'conditional waypoints' & unfortunately can't be entered by the flight crew. They can only be entered into the database as SIDs or STARs by the powers that be.
Regarding the third question, you should be able to enter the runway threshold as a waypiont in either the legs page or the fix page, eg. RW19 (it might be RWY19 - my memory is getting a little dim!). When you type this in you will get a number of waypoints to chose from, particularly if there are a number of airports in with the same runway direction in the area, so be carefull to get the correct one. They are listed in the order of closest one first. If you are close to the airport, the correct one should be at the top. Then, on the legs page you then put this point to the top of the page (if you didn't enter it there in the first place) & type the inbound track into the bottom right corner. On the fix page just put the reciprocal track in as a radial.
Sorry, I don't know the answer to your last question, but if I remember rightly, all the user defined waypoints are cleared after landing - not sure though!
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Bally - the best solution is to fly the a/c! With the trackline available is is so easy. IF you must fly in auto, do as you say - programme r/w c/l +20nm as WPT1, next WPT on the route as WPT2. As you approach 3000' in LNAV, ask other pilot to select new WPT and execute at (or just before) 3000'.
As for Q3, I cannot see how you can have all these 'waypoints' in the way? Can you explain? As oak says, unless the waypoints are in the SUPP database, they clear after 'weight on wheels'. Otherwise clear them before startup.
As for Q3, I cannot see how you can have all these 'waypoints' in the way? Can you explain? As oak says, unless the waypoints are in the SUPP database, they clear after 'weight on wheels'. Otherwise clear them before startup.
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Why bother to create a SUPP WPT for a base leg? If you must have a magenta line on base leg why not define the point as a range and bearing from the threshold or other local navaid/waypoint in the scratchpad?
As BOAC says, fly the aeroplane: every day I see FOs carefully crafting complex imaginary downwind and base legs that they are never going to fly because that is not where they're vectored to. The need for a comforting magenta line at all times bespeaks an over reliance on the FMC imho - what more do you need than an extended centreline if on radar vectors to finals? The magenta line and the data it generates is misleading and inaccurate if you're not actually flying it.
As BOAC says, fly the aeroplane: every day I see FOs carefully crafting complex imaginary downwind and base legs that they are never going to fly because that is not where they're vectored to. The need for a comforting magenta line at all times bespeaks an over reliance on the FMC imho - what more do you need than an extended centreline if on radar vectors to finals? The magenta line and the data it generates is misleading and inaccurate if you're not actually flying it.
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Sometimes, one longs for the olden days where, on the 737 for a complicated departure, one just turned off the box, turned off the F/D A/T and so forth ... set up the RMI picture or whatever rocked one's boat .. and flew off just like in a lightie ... can't recall ever getting terribly lost in the ensuing gyrations ...
In Australia, where we didn't have all that many international DMEs (as opposed to the far superior local Oz DME which is no more) the magenta line was, at best, a misleading work of fiction when the aircraft was away from the main cities so most of us paid not all that much attention to it ...
In Australia, where we didn't have all that many international DMEs (as opposed to the far superior local Oz DME which is no more) the magenta line was, at best, a misleading work of fiction when the aircraft was away from the main cities so most of us paid not all that much attention to it ...
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I can assure you I'm not an MS pilot! I personally prefer to hand fly using the extended centreline with the scale at 5nm and then just get the heading matched before engaging the A/P. The reason is that it was one of a number of ideas to try and stop people not following the proper noise procedure as they were instinctively going to LNAV to the first waypoint. However as Oakape kindly advised, the fact you can't make the condition of the turn to be 3000ft unless its a pre-programmed SID, then it wouldn't really work - so you can disregard the first bit!
My terminology isn't quite right as regards supp wpts, of course you wouldn't create one for a base leg. What I meant is take runway 27 for example, centrefix is CI27, I make a point of CI27360/4 - when it throws up the list of waypoints (usually the first one being the right one), but they are all miles away scattered across Europe - 33North instead of 51North for example. To get it to work I had to try and think of a more obscure one e.g. CI27350/4.2 or something. I'm trying to figure out if I'm doing something stupid, or there is some way of clearing out all the other possible points it is suggesting?
Again, this isn't something I do every day, nor should it ever replace the 3x tables and a bit of common sense- but sometimes when vectored to the opposite side of an airfield, CDA requirements etc, its nice to have a rough profile in the box, thats all..
Thanks
My terminology isn't quite right as regards supp wpts, of course you wouldn't create one for a base leg. What I meant is take runway 27 for example, centrefix is CI27, I make a point of CI27360/4 - when it throws up the list of waypoints (usually the first one being the right one), but they are all miles away scattered across Europe - 33North instead of 51North for example. To get it to work I had to try and think of a more obscure one e.g. CI27350/4.2 or something. I'm trying to figure out if I'm doing something stupid, or there is some way of clearing out all the other possible points it is suggesting?
Again, this isn't something I do every day, nor should it ever replace the 3x tables and a bit of common sense- but sometimes when vectored to the opposite side of an airfield, CDA requirements etc, its nice to have a rough profile in the box, thats all..
Thanks
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I'm a little confused as to what you are trying to do. Let's assume you cannot work out your energy level without the FMC. You talk of being 'sent' to the 'other side of the field' - I cannot quite see how your carefully created WPT, now in the wrong place, is going to help? How are you creating this WPT? In legs? In which how is it named? Presumably you would, having made it, 'join up the dots'? Why not use the fix page? 'BaseA' and 'BaseB'? IF you are talking about constantly having to reconstruct your route in the FMC - you should be doing other things.
I would seriously suggest you put some effort into working out where you are and where you want to be WITHOUT the Waypoints. Try a 10 mile range ring on the runway or CI as a starter - you can view this as like using a nicotine patch, and you can set it up waaaay before anything gets 'busy'. You can work from there to range and bearing from 'something' to 'fix' yourself on your mental map and soon you will find that 'DR' circuit in your head becomes 'live' again. As Ag Bis posts, constructing ornate patterns that you will probably not fly is a bit of a waste of time.
I would seriously suggest you put some effort into working out where you are and where you want to be WITHOUT the Waypoints. Try a 10 mile range ring on the runway or CI as a starter - you can view this as like using a nicotine patch, and you can set it up waaaay before anything gets 'busy'. You can work from there to range and bearing from 'something' to 'fix' yourself on your mental map and soon you will find that 'DR' circuit in your head becomes 'live' again. As Ag Bis posts, constructing ornate patterns that you will probably not fly is a bit of a waste of time.
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This is why pprune drives me mad at times.
I had hopes that by posting on the technical forum I would get a technical response instead of the usual 'why are you asking that, you're clearly an idiot'!
I very seldom create anything much other than the occasional point here and there, I just recently tried doing this and found a problem - that's why I'm asking about the problem, not what everyone thinks about why I'm doing it!
Centrefix runway 27, CI27
Line selected in legs page and 360/4 added to make a nice little point 4 miles to the North (why, when, where is irrelevant!)
Line select the point to the line above
Says something like 'select desired wpt' with a list of them
They are all no where near where I am, e.g 33N not 50N
I understood the nearest and therefore correct point was at the top.
Any ideas?
Thanks
I had hopes that by posting on the technical forum I would get a technical response instead of the usual 'why are you asking that, you're clearly an idiot'!
I very seldom create anything much other than the occasional point here and there, I just recently tried doing this and found a problem - that's why I'm asking about the problem, not what everyone thinks about why I'm doing it!
Centrefix runway 27, CI27
Line selected in legs page and 360/4 added to make a nice little point 4 miles to the North (why, when, where is irrelevant!)
Line select the point to the line above
Says something like 'select desired wpt' with a list of them
They are all no where near where I am, e.g 33N not 50N
I understood the nearest and therefore correct point was at the top.
Any ideas?
Thanks
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No need to get batty, rally. Some of us are are trying to help you become more of a pilot that a button pusher
God only knows we need a few.
Now then, back to topic: What is the displayed name of the new WPT you have created?
I suspect you have a Supp database stuffed full of created waypoints by eager picture makers. Get your drivers' handbook out before you aviate next time and clear the database before you go. It will clear itself on db update.
God only knows we need a few.Now then, back to topic: What is the displayed name of the new WPT you have created?
I suspect you have a Supp database stuffed full of created waypoints by eager picture makers. Get your drivers' handbook out before you aviate next time and clear the database before you go. It will clear itself on db update.
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Sorry, its just annoying that when you ask a technical question about buttons it makes you a 100% button pusher 
There's nothing I love more than hand flying, without map mode or the occasional visual approach. It annoys me greatly that some operators go to great lengths to discourage visual approaches and even then insist you must construct a path in the FMC to avoid being hot and high - I would argue people are hot and high because they never do visual approaches and aren't used to eyeballing things and have become so reliant on using the FMC for all the path guidance!
Anyway... back to the point!
I think the confusion is between supplementary waypoints and temporary waypoints. I've already cleared out the supplementary waypoints database (SUPP NAV DATA) - and understand from the manuals that all the temporary (TEMP NAV) are deleted on landing anyway.
I'm not trying to create a supplementary or new waypoint, I'm just creating a temporary one in the legs page from an existing one as I've explained previously. The issue is when it says "SELECT DESIRED WPT" as soon as I try to select it above the existing centrefix point, and gives me a list of possible options, none of them are anywhere near where I want them to be. Does anyone know where the logic of the order of this page comes from? I always thought it presented nearest first in the same way if you select a VOR in the FMC and there is more than one of them.
I will try and take a few pictures of the problem - as they say it speaks a thousand words. The point is called CI2701 once its inputted on the legs page - this is what the FMC called it, not me obviously.
There's nothing I love more than hand flying, without map mode or the occasional visual approach. It annoys me greatly that some operators go to great lengths to discourage visual approaches and even then insist you must construct a path in the FMC to avoid being hot and high - I would argue people are hot and high because they never do visual approaches and aren't used to eyeballing things and have become so reliant on using the FMC for all the path guidance! Anyway... back to the point!
I think the confusion is between supplementary waypoints and temporary waypoints. I've already cleared out the supplementary waypoints database (SUPP NAV DATA) - and understand from the manuals that all the temporary (TEMP NAV) are deleted on landing anyway.
I'm not trying to create a supplementary or new waypoint, I'm just creating a temporary one in the legs page from an existing one as I've explained previously. The issue is when it says "SELECT DESIRED WPT" as soon as I try to select it above the existing centrefix point, and gives me a list of possible options, none of them are anywhere near where I want them to be. Does anyone know where the logic of the order of this page comes from? I always thought it presented nearest first in the same way if you select a VOR in the FMC and there is more than one of them.
I will try and take a few pictures of the problem - as they say it speaks a thousand words. The point is called CI2701 once its inputted on the legs page - this is what the FMC called it, not me obviously.
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As the Cpt says, I would expect CI201. I cannot imagine there would be that many WPTS created with that name? Are you getting several? If there are, selecting the correct lat and long should be do-able?
Are you certain you are clearing the SUPP? Best done at INIT before you type anything else into the CDU.
Are you certain you are clearing the SUPP? Best done at INIT before you type anything else into the CDU.
I understand perfectly what ballyboley is saying here. Creating a user-defined waypoint from the Capture Intercept point for runway 27 (CI27) is resulting in the display of the "SELECT DESIRED WPT" page, with a list of "CI27" waypoints, none of which appears to be the desired one. It is after selecting one of the waypoints, that the user defined "CI2701" waypoint is appearing on the LEGS page - but not where he wants it, as it is not defined from the Capture Intercept point desired.
The problem is that the FMC system can contain only six waypoint names which are not unique - and the particular CI27 point you are trying to access is not contained within the waypoint database.
Perhaps your best bet would be to define a runway extension point of your own, at the required distance. Go to the APP page, and select the runway you desire (it will be below the runway approaches, you may have to page down to find it). Once selected, you will then see two dashes, a decimal point and another dash at the bottom right. Enter in the desired distance from the runway, and you will have defined a runway extension point on the LEGS page. You may then use this point as the basis for your user defined 360/4 base point.
The problem is that the FMC system can contain only six waypoint names which are not unique - and the particular CI27 point you are trying to access is not contained within the waypoint database.
Perhaps your best bet would be to define a runway extension point of your own, at the required distance. Go to the APP page, and select the runway you desire (it will be below the runway approaches, you may have to page down to find it). Once selected, you will then see two dashes, a decimal point and another dash at the bottom right. Enter in the desired distance from the runway, and you will have defined a runway extension point on the LEGS page. You may then use this point as the basis for your user defined 360/4 base point.
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I know what YOU are saying about WPTS, but it is not what BB is saying.
" when it throws up the list of waypoints (usually the first one being the right one)"Personally I would, like ab, take your last para and just make myself a simple Fix called BALLY in the right place then line select. (Hoping there is not a WPT called ........)
" when it throws up the list of waypoints (usually the first one being the right one)"Personally I would, like ab, take your last para and just make myself a simple Fix called BALLY in the right place then line select. (Hoping there is not a WPT called ........)
wheres my RMI??
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Checkboard - thank you, I was beginning to worry I'd actually gone insane. That seems to be exactly the problem, as other runways e.g. CI22 are OK - the CI27 must be another CI27 and not the one I'm using which is interesting as it obviously uses CI27 from the overall database, not from the legs page I picked it from. The strange thing is that sometimes this doesn't happen and it works fine - could it be to do with the order of the legs and any discontinuity or preceding point problem?
I will put up a step by step photo collection soon if I can recreate the problem!!
And yes, its CI201 - Glad you spotted the deliberate mistake
And yes, its only called CI201 after I pick it from the list of "select desired wpt" If there were more it would be CI202 and so on.
The supp database is empty, and believe would only be relavant if I created a new point from scratch, not a temporary one using bearing/distance from an existing legs page capture intercept point.
I will put up a step by step photo collection soon if I can recreate the problem!!
And yes, its CI201 - Glad you spotted the deliberate mistake
And yes, its only called CI201 after I pick it from the list of "select desired wpt" If there were more it would be CI202 and so on.
The supp database is empty, and believe would only be relavant if I created a new point from scratch, not a temporary one using bearing/distance from an existing legs page capture intercept point.
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The supp database is empty, and believe would only be relavant if I created a new point from scratch, not a temporary one using bearing/distance from an existing legs page capture intercept point.
Bally - as your posts move on, I detect you are not a 'magenta line' pilot at heart? The FMC is a tremendous source of information and can be used without the minutiae of detailed planing based on 'CI27' or whatever. EVERY approach I flew had airport (or 10 mile final for an ILS) in FIX 1. Speed and heights worked out 'in me heed' on that. That was enough. If you feel you need (or perhaps 'should') have some intermediate WPT, why not make one to suit the day rather than one based on a database approach? Would you not be better, say for a 'smokin' visual to roll out at 600' on final, just using either FIX range or DME? For an ILS into somewhere quiet, 15 off at 20nm, and for EDDF or LFPG, centreline at 40nm
? All done via fix page on the airport - which is unique - so all your 'database' worries go away. Otherwise as the dbases grow as they inevitably do, I fear you will forever be fighting them.
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Couldn't agree more BOAC, however like any system on the old hairyplane - if there's something I dont understand I wont give up until I figure it out. Needless to say I did not spend half the descent constructing a beautiful magenta line and promptly said "sod it" - but its just one of those things I'd like to figure out some time!
Cheers for the info
Cheers for the info
