LNAV Issues?

[Chuck Adams 0]

I am using v. 1.0.18 on MSFS 1.26.5.0.  In the past few days I have flown a couple of non-SID departures and been unable to command a direct-to to the first waypoint on my plan.  As an example, on a flight from KMAF to KCRP, my plan was FUSCO J15 JCT J2 SAT J25 CRP.  I took off and flew runway heading to about 1000 ft, then used the heading mode to turn the aircraft toward FUSCO.  I then went to the legs page, clicked on FUSCO to put it in the scratchpad, then tried to re-enter it as my next leg.  This gave me a "NOT ALLOWED" message that I was unable to clear.  

 

I also noticed that the MFD was showing the distance to JCT, which was the second waypoint in the FMS.  And the HSI in the PFD was showing the course to JCT, not FUSCO. 

 

I have several hundred hours on this aircraft (using MSFS), and have not had this problem before.  I discovered that if I use the HDG mode to fly to my first waypoint, and get the aircraft aligned on the path to the second waypoint (as depicted in the HSI), the CRJ will fly the rest of the route with no problems.  But with the direct-to function now broken, this aircraft is of limited use, especially when flying on VATSIM with ATC.  Also, this has only been going on for a few days; perhaps as long as a week.  I mentioned the versions above, which is what is on my computer now.  I really cannot say if a MSFS or CRJ update was when I started noticing this problem, and I usually don't worry about what I have installed until I am trying to describe a problem.  

 

I hope this helps someone on you development team.  

 

 

[Joe Markowski 139]

So I'm confused as to what you're doing.  You say you tried to insert it as the next leg on the Legs page, then later you say that Direct To doesn't work.

 

I haven't had a problem with Direct To, but the Legs page issue seems correct and not how to go direct at all.

[Richard Dastardly 108]

Ooh boy yes, some systems are getting awfully confused - progress page thinks it's on FUSCO-JCT, hud WP target is JCT, aircraft.. .steering somewhere. DCT INTC & entering FUSCO did actually point the plane at FUSCO, but the hud target didn't change ( is it meant to? ). Reaching FUSCO sent the a/c towards JCT, and reaching JCT has sequenced the hud to LEJON, so functionally it seems ok.

 

Don't think you can copy a waypoint over itself, which seems to be what you were trying to do ( I mean, why would you ). You can copy later WPs over the current one.

 

Edit: took another look at the FPLN page, first WP is now DCT JCT, when I did enter DCT FUSCO & it was originally showing that.

[Richard Dastardly 108]

Oops, think I found out what *I* did at least - originating runway didn't get entered somehow, so the FMS didn't generate an originating WP. What does the real one do? either way might need a basic sanity check there. If I were writing a FMS I'd probably default the initial waypoint to the aircraft's position when the first leg is created, but I don't write FMS, thankfully!

 

 

Please login to display this image.

Second go at the flight is going properly. Didn't need to do anything special, just gained some altitude on runway heading & put it in NAV. Need to try that somewhere with a closer first waypoint sometime.

[Chuck Adams 0]

Well, thanks for the reply.  However, the LNAV feature is absolutely NOT working as it should.  As I write this I am flying on another compter using a different sim, so can't send you any screen shots.  When I was attempting do describe this issue, I knew it was complex and I was not describing it adequately.  However, I cannot imagine that I am the only one seeing this problem.  I'll keep watching this forum, and if nobody else chimes in I'll do another flight and take some screenshots.  Again, thanks for the effort you put into your reply.  

 

[Chuck Adams 0]

Try this--put your CRJ at any airport.  Load the FMS with waypoint1, waypoint2, etc.  and a destination.  Take off, but in heading mode; preferably not heading direct to waypoint1 (perhaps the waypoint is east of the field, and you take off to the west).  Use the heading mode to control the flight, and when you get the CRJ pointed toward waypoint1 (but not on the route line on the map), got to the legs page, put waypoint1 in scratchpad and try to re-enter it as the active waypoint.  I get "NOT ALLOWED", and it pretty much locks me out of using that FMS.  Look at the progress page, the MFD and the HSI--they are probably showing the heading and distance to waypoint2 even though the active (magenta) entry on the progress page is waypoint1 (as it should be).  

 

Sorry, this is from memory.  I will shift back to the CRJ in a few days and provide screenshots.  

 

[Richard Dastardly 108]

On 8/20/2022 at 12:11 AM, Chuck Adams said:

and when you get the CRJ pointed toward waypoint1 (but not on the route line on the map), got to the legs page, put waypoint1 in scratchpad and try to re-enter it as the active waypoint.

We were asking why you are doing this - you are saying "copy waypoint1 over waypoint1 to make it active", which makes absolutely no sense. In my last flight on your route I took off & flew in HDG to gain altitude for a while, not pointing at the current WP - the current WP started as FUSCO & stayed FUSCO no matter what mode I had the aircraft in, until I reached it.

 

The *previous* flight had problems - I'm pretty sure because the runway entry didn't stick for whatever reason ( probably me not checking properly ) and the FMS chose FUSCO as the originating waypoint & then got partly confused. I fixed that by putting FUSCO in via DIR INTC page, not by playing with the legs page.

[Chuck Adams 0]

I almost always remember to enter the departure runway, even if there is no SID in my plan.  So why did I copy waypoint 1 and re-insert it to make it active--it is because if the plane is not on the path already in your FMS (and as depicted on the your map display), that is how you intiate a direct-to order--re-insert, activate, and engage LNAV.  Remember, at the point I did this my plane was well off the planned route as depicted on my map display because weather favored taking off on the runway pointed away from the first waypoint.  I used the HDG mode to turn towards the first waypoint, then tried to execute a direct-to in order to rejoin my planned route of flight.  

 

Later today I will do another flight in the CRJ and capture some screenshots that, hopefully, allow me to illustrate what I am seeing.  

 

[Joe Markowski 139]

3 hours ago, Chuck Adams said:

 that is how you intiate a direct-to order--re-insert, activate, and engage LNAV.  

No, the correct way to do direct-to is to go to the DIR INTC page, select the waypoint, then hit EXEC.

[Chuck Adams 0]

Well, I tried out the CRJ again today.  First I was off-line, and everything worked just fine.  Same software versions in MSFS and the CRJ as mentioned at the start of this thread.  So, I restarted MSFS and flew the flight again--on VATSIM.  I happened that the wind favored 34L so as instructed by ATC I took off, flew runway heading, and at about 5000 feet I got one vector, then direct to FUSCO.  I flew an RNAV approach at KCRP, which required closing a discontinuity and then commanding another direct-to (to the IAF for the approach); no problems here.  

 

I took plenty of screenshots during the first flight in order to better illustrate my "problem".  However, in both flights the CRJ's FMS performed flawlessly.  After landing in KCRP I updated the AIRAC date to the current cycle, departed KCRP, and again the CRJ is performing flawlessly.  So while I do not know what was going on, it seems to have resolved itself.  

 

I DO appreciate the responses.  

[Chuck Adams 0]

Joe, 

 

I used both techniques to test the direct-to (both when it was working for me, and when it was not).  But most of the aircraft (PMDG-777, -737, QW 787, FeelThere E-175 and a few others) work just fine without having to shift over to the direct-to page, so normally I monitor the legs page and use it for direct-to.  

 

Thanks again for the input.  

 

[Richard Dastardly 108]

I have to admit to copying later waypoints over the current one to cut out bits of the FP in the legs page ( in both the CRJ and the 146, which is the only other thing with a FMS I fly ), but I've never done that with the current one itself. Deliberately going direct to the current waypoint is a confusing idea if the aircraft isn't going to the active waypoint then there's something a bit wrong with either the nav system or the display - and in this case I think the displays do get a bit confused at times, cf my initial WP in the FPL changing all by itself. I still think the root cause is my departure runway not getting entered but the ambiguous state that leaves the FMS in is not good.

[Chuck Adams 0]

Pretty simple (except in this instance).  Go to the Legs page, click on the LSK next to the active leg, which puts it into the scratchpad, click the same LSK again and activate LNAV.  However, this works best if you are more  or less headed towards that waypoint.  Works fine in everything with an FMS that I have ever flown.  

 

Hope you get things working to your satisfaction right away.  

 

[CRJay 427]

On 8/22/2022 at 10:43 PM, Joe Markowski said:

No, the correct way to do direct-to is to go to the DIR INTC page, select the waypoint, then hit EXEC.

 

Both ways are equally feasible in real life. Setting the desired waypoint on LSK2 or going via the DIR INTC page.

[Joe Markowski 139]

6 hours ago, CRJay said:

 

Both ways are equally feasible in real life. Setting the desired waypoint on LSK2 or going via the DIR INTC page.

Even if the desired waypoint is already the first and active waypoint?

[CRJay 427]

1 hour ago, Joe Markowski said:

Even if the desired waypoint is already the first and active waypoint?

 

Yes. For example, if you are inbound to that waypoint, but get an assigned heading due to traffic or military activity for example, then get cleared back inbound that waypoint. You can still do it either way. Some pilots like to do it if the initial turn prediction is a bit off (e.g. setting the direct to at speed of 210kts but while turning to the waypoint still accelerating). In those cases the initial LNAV line on the MFD will look a bit off and as though you are overshooting. Some people then set the waypoint again in the LEGS page to get it looking pretty again. Personally I just tend to let the plane sort it out.

[Richard Dastardly 108]

Related question for the CRJ pilots, what does the LEGS page look like before departure if you haven't put an originating runway in yet? if you've ever managed to be in that situation. In the model the active WP ( at the gate ) is the first WP, but there's no blue leg origin entry. As soon as you add a runway, that enters as the leg origin. I suspect if you take off without the runway entry the FMS will start sequencing & decide the head of the legs page ( which I assume is literally just listing the internal WP list ) is the origin. Sanity wise it does feel like the aircraft should take it's location at weight off wheels ( plus enough seconds to be sure ) & compare that to the first leg entry to see what it should sequence, but no idea what it actually does.

[jay jay 93]

On 8/29/2022 at 8:40 AM, Richard Dastardly said:

Related question for the CRJ pilots, what does the LEGS page look like before departure if you haven't put an originating runway in yet? if you've ever managed to be in that situation. In the model the active WP ( at the gate ) is the first WP, but there's no blue leg origin entry. As soon as you add a runway, that enters as the leg origin. I suspect if you take off without the runway entry the FMS will start sequencing & decide the head of the legs page ( which I assume is literally just listing the internal WP list ) is the origin. Sanity wise it does feel like the aircraft should take it's location at weight off wheels ( plus enough seconds to be sure ) & compare that to the first leg entry to see what it should sequence, but no idea what it actually does.

On a related question for RL CRJ pilots.  Do you always enter the full info for the destination airport, i.e. - the STAR and Runway or just leave those off the flight plan until you get closer and then enter prior to TOD?

[amahran 601]

13 hours ago, jay jay said:

On a related question for RL CRJ pilots.  Do you always enter the full info for the destination airport, i.e. - the STAR and Runway or just leave those off the flight plan until you get closer and then enter prior to TOD?

Not sure if you’ll get an answer in due time from actual pilots, so I’ll give you my understanding: it hinges on the airline’s SOPs. Sometimes they require pilots to input the whole flightplan end-to-end (including arrivals and runways). Some may say that certain flights above a certain length do not require an actual arrival to be inserted prior to departure due to changing winds, etc.. Overall, it’s context dependent. 
 

What I do in flight sim is…if it’s under 3 hours, I select the arrival based on the TAF. Anything else, I leave it blank until I get within an hour of arrival.

[CRJay 427]

On 8/29/2022 at 3:40 PM, Richard Dastardly said:

Related question for the CRJ pilots, what does the LEGS page look like before departure if you haven't put an originating runway in yet? if you've ever managed to be in that situation. In the model the active WP ( at the gate ) is the first WP, but there's no blue leg origin entry. As soon as you add a runway, that enters as the leg origin. I suspect if you take off without the runway entry the FMS will start sequencing & decide the head of the legs page ( which I assume is literally just listing the internal WP list ) is the origin. Sanity wise it does feel like the aircraft should take it's location at weight off wheels ( plus enough seconds to be sure ) & compare that to the first leg entry to see what it should sequence, but no idea what it actually does.

 

No clue, I have never started a RL flight that way. You always know the runway for departure, and if you know it, why would you not put it in?

 

15 hours ago, jay jay said:

On a related question for RL CRJ pilots.  Do you always enter the full info for the destination airport, i.e. - the STAR and Runway or just leave those off the flight plan until you get closer and then enter prior to TOD?

 

There is a slight chance that SOPs might make a difference, but I don't think they really do. Anyway, for us, it is always the full plan, whether it is a 20 minute flight or a 3 hour flight. We have many tools at our disposal with all the weather information, so we can make a solid guesstimate of which runway will be in use and which arrival to expect based on the flightplan. In my opinion, there is no reason to leave it blank 'because the weather and runway in use might change'. If that happens, you change it as soon as you have updated weather/airport information. And if you put in all the data at the start of the flight you will generally get more accurate time and fuel predictions.

 

[Richard Dastardly 108]

16 hours ago, CRJay said:

 

No clue, I have never started a RL flight that way. You always know the runway for departure, and if you know it, why would you not put it in?

 

I don't know how you'd end up in that situation - my own training & various jobs make me consider these sorts of ambiguities, so I ask just in case.

[jay jay 93]

On 9/5/2022 at 2:44 AM, CRJay said:

 

There is a slight chance that SOPs might make a difference, but I don't think they really do. Anyway, for us, it is always the full plan, whether it is a 20 minute flight or a 3 hour flight. We have many tools at our disposal with all the weather information, so we can make a solid guesstimate of which runway will be in use and which arrival to expect based on the flightplan. In my opinion, there is no reason to leave it blank 'because the weather and runway in use might change'. If that happens, you change it as soon as you have updated weather/airport information. And if you put in all the data at the start of the flight you will generally get more accurate time and fuel predictions.

 

How common is it for ATC to throw a last-minute runway change at you?   And what would be the latest stage of your approach where this could be implemented?     I was watching Flight Aware a few days ago and KBOS had to switch runways (assume due to wind change). It was amazing to see all those jets changing to different headings and getting re-sequenced to the new runway.  Masterful job by ATC, especially since this was during "rush hour". 

[CRJay 427]

On 9/7/2022 at 2:50 PM, jay jay said:

How common is it for ATC to throw a last-minute runway change at you?   And what would be the latest stage of your approach where this could be implemented?     I was watching Flight Aware a few days ago and KBOS had to switch runways (assume due to wind change). It was amazing to see all those jets changing to different headings and getting re-sequenced to the new runway.  Masterful job by ATC, especially since this was during "rush hour". 

 

In my experience in Europe, not that common. Some larger airports like Frankfurt or Charles-de-Gaulle will sometimes ask if you can accept a late change. It will often then be a visual side step to a parallel runway. If you have the time to have a quick look at any changes that may bring, like missed approach procedures etc, it is usually fine. Often it is also anticipated and briefed already (eg. "in case of side step, we do this this this). I do not think I have ever had it asked of me below roughly 1700ft.

 

I find that in Europe, runway changes seem to be mostly planned ahead quite well. So there is very little scrambling around. They will sort of pick a cutoff point, like everyone within X nm of the airport will finish inbound the current runway, as long as wind limits permit, and the rest get the new runway.