We continue to make the point in the hope that Asobo will turn their attention from elephants and fauna to improving and, hopefully, fixing the navigational systems in the commercial aircraft models.
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ie Stop Monkeying around … yes, 100% agree … but it would seem that Eye Candy, and wild animals sell MSFS to a large number with itchie Steam & MS Store purchasing urges …
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Cannot disagree with you on that one.
The G3000 is currently undergoing a full map system rewrite and the G1000 just went into beta (we have a link on our Discord) and has been largely rewritten from the ground up. The performance of the G1000 is unreal. I get a decent fps boost with it running.
The fully rewritten flight plan management system that debuted on the CJ4 yesterday fixes USR waypoints and more. It also adds proper vectors legs, intercept legs, discontinuities and greatly increases the accuracy of even the existing NavBlue data (which is actually quite good when fully utilized). On top of that, approaches getting corrupted when loading them with things like the AP turning around, or not being able to change the approach at all by going direct or deleting fixes are also issues that we resolved.
We will be rolling out our flight plan management system as well as the VNAV and RNAV (with LPV) we just released on the CJ4 to the Garmin units within the next month or so.
-Matt
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Sounds absolutely wonderful. All credit where it is due.
FBW are also working on an AP system of their own for the A320 which I am sure will be also be a success.
I really respect those who are working on these projects. I am though also sad that Asobo/Microsoft did not think the problem sufficiently relevant to put these topics higher in their list of priorities.
As one correspondent above suggested, eye-candy sells.
Can’t wait to see the G3000 in the TBM. I just wish you could transfer the coding logic to the A320 as well lol.
Really wish you well with your project.
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We’ve built these systems to be portable, so they can be used in any project, and we very much hope they will be.
-Matt
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Ok. That news made me feel tingles I shouldn’t feel when talking about a flight sim. Your team is amazing. I may have to pop over to the discord and check out the G1000.
Any timeframe for the G3000 beta?
You and me both. I fly both the TBM and Longitude a lot. A big part of why I love those planes is the G3000. I’ve been using the mod since it’s been available, and couldn’t imagine not using it. I’m extremely happy that extended functionality is being added as well as replacing the buggy and under features stock code in the sim.
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I have a lot of technical questions but think you guys are doing great work and a great service. I certainly don’t want to dampen any excitement, so here is my carefully phrased question:
It’s well known that the core Asobo AP flight control logic has bugs limiting its ability to realistically turn to a new heading, intercept a VOR radial or FMS course, and intercept an ILS localizer. So is it correct to say that the FBW team’s AP system currently replaces the Asobo AP flight control, or is currently depending for Asobo core AP fixes before we have realistic AP again?
And just to make sure I tie into this thread properly, Asobo uses the USR waypoints as a way to (sometimes erroneously) make the AP fly their desired course. Real APs have to deal with fly-over waypoints, and fly-by waypoints. Real pilots get realistic vectors decided by a real ATC control with that incredible human brain, whereas the Asobo logic tries to figure things out on your PC that has less common sense than your annoying little barky Chihuahua, and adds USR waypoints for the AP and ATC to fly / vector to / from.
I think Matt will agree – just getting rid of them is not the answer. Asobo either needs to fix the core logic or third parties (like the FBW group) will have to nearly completely replace the flight plan logic of AP system.
Oh, and BTW, “activating” an approach in the sim essentially places a USR waypoint at your current position and executes a direct-to to the initial approach fix (or transition fix) you’ve programmed. It unfortunately does this even is you are already on the approach past the IAF. This creates the turn-around behavior we see.
Secondly, if your flight plan has discontinuities, that means you have not adequately told the flight planner logic how to get from some fix to another fix. In real life, you have to fix those discos or the AP doesn’t know what to do. At least the sim puts in some USR waypoint so you can see that there is a problem.
So correct me if I’m wrong, but if you see USR waypoints, those represent discontinuities. Normally, you should fix those with legs between two fixes – for example, choose a STAR and make sure the approach transition starts at one of the STAR’s fixes. And if the approach specifies “radar required”, in the real world that means you will be getting radar (ATC) vectors. If you’re doing such an approach in the sim, either the USR waypoints will look right (as if a controller was setting them), or you need to take over your own vectoring to get cleanly from the last good fix to the next good fix. Once at the next good fix, you should activate that leg and you should be good to go until the next discontinuity.
In other words, the USR fixes are symptoms of insufficient flight planning in the sim environment with the current Asobo flight plan logic. FBW is attempting to create logic that includes practical reasoning and instructions by a human ATC? If they can pull it off, they have my vote for third party (free?) developer of the year!
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VERY well put!
I still have a hard time flying GPS. Just an old man’s distrust. I prefer planning my flights along airways and utilizing the radio aids to get me lined up. They have been around a long time and I dare say that plenty of users on this forum have sat in the back of an airliner, shooting an approach through a storm without ONE digital screen in the plane and nothing but a couple needles guiding the crew to the centerline. They just didn’t know it.
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Just to be clear here, I am part of the Working Title team, not the FBW team, so I can’t speak to their efforts. I will describe what we’ve done though (this will be long):
The flight plan management system is entirely new, from the ground up. We now walk through the sim provided procedure data to generate the appropriate legs and terminators. The sim procedure legs data is actually really good (even with stock data), and has all the different legs types you would expect to find in standard ARINC data, like track to fix, course to DME distance, heading to intercept, heading to altitude, heading to manual termination, etc.
In real FMC data, there are many fixes that don’t have specific names but it’s left up to the FMC to generate a name for them. One example of that would be a heading to manual termination leg. These are basically the equivalent of the instruction “fly heading xxx until vectored by ATC” in the procedure chart. In the CJ4, this becomes a fix with the name (VECT) and then a discontinuity is added after that fix that the FMS will not sequence past, because it needs instructions from you in order to proceed. Another example of this is course to DME distance legs, which normally get something like the format D125J, where the numbers there are the course and the final letter is the distance in NM (A is 1NM, B is 2NM, etc). These fixes are not ICAO fixes that you could enter into the FMC by hand, but they are legs and they do have terminations, and will be parsed and pulled when that procedure is selected.
We’re doing the same thing with the provided procedure legs data, and generating the correct leg tracks and termination positions based on the data and a lot of spherical trig. In the stock flight plan system, you will often see USR or USER fixes for a couple of these leg types, but there are also a bunch of leg types that the stock flight plan manager completely skips, leading to the complaints you see about how the navdata is bad. It isn’t bad, actually, it just isn’t being used to the full extent it can be. USR fixes are not related to anticipated ATC instructions or flyover fixes. The stock flight plan manager just skips any manual termination legs completely (which is where you would be vectored).
There are other places that FMCs will normally place discontinuities, such as before the approach so you don’t accidentally sequence on to it before you’ve cleaned up and validated the legs. Finally, this revamped flight plan management system is already available as of Tuesday evening on the CJ4. So you can fly it now, it’s not just an idea or an implementation to be explored, it works today. You can modify the plan in any way that you want, do direct to any fix you desire, even change your approach when you’re already on the approach, all without any navigation interruptions whatsoever. The AP will not send you back to fixes that you’ve passed, you won’t get waylaid back to your origin airport, none of that stuff.
As to controlling the plane along this new, accurate route, we haven’t completely written a new AFCS control system (although it is planned), but we do have custom lateral and vertical navigation, which under the hood uses the heading lock and vertical speed hold modes of the stock AP to generate angular and vertical instructions for the aircraft to fly, which works actually extremely well. The limitations with the Asobo AP aren’t related so much to the actual flight control as they are with the underlying generated fixes. So, we’ve designed a full AP system over the top using those modes underneath, so the experience is seamless and correct to the actual aircraft, including all the correct FMA annunciations. Because the navdata is actually quite good and includes all the right altitude restrictions, we’ve also included a full VNAV implementation, and for good measure we also included the ability to actually fly real RNAV, with correct nav sensitivity changes in the terminal and approach regions, including LPV (with proper angular sensitivity).
Hopefully that lends some more insight into how it works right now, but I’m always happy to answer any more technical questions anyone might have!
-Matt
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I always get the WT and FBW group mixed up. Sorry.
You answered the question I was asking. We’re (any third parties or mod groups) are stuck waiting on Asobo core AP functionality fixes for things like heading changes and course intercepts. You can change the flight plan and change modes on the AP, but the way it flies – max bank angle, max bank angle hold time, roll-out behavior, etc. – we’re still at their mercy for those fixes.
So if Asobo fixes the AP flight behavior in the Dec 22 patch, and you guys have already fixed the flight planning bugs, it’s going to be a good Christmas break!
So what happens if there are discontinuities and you don’t link them up in FMC prior to starting flight? What is the behaviour once the aircraft reaches a discontinuity? Does it stop following the plan? Does it go to the next “definited” waypoint?
Yes and no. With some clever manipulation we’ve got the roll-out behavior a lot better. It now rolls out with 15 degrees left at about 10 degrees/sec, about as it should. Not everything is perfect, but I encourage you to try it out and see how you like it. 
In the CJ4 if the FMS sequences into (i.e. it actually reaches while flying in NAV) a discontinuity the plane will enter HDG mode with the current heading as the selected heading. As soon as you manually sequence past it by either clearing the discontinuity or going direct-to to a fix beyond it, you can re-engage NAV mode and it will continue on along the plan.
-Matt
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Thanks, Matt! Oh, hey! A fellow drummer!
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Yes indeed, for many many years professionally! Lead software architect now, though, but I still gig when I can. Definitely miss it a lot at times. 
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Nice, I am a Berklee-trained fusion cat.
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Lead SA. Nice.
Would have been hard pressed to get Lead Drummer. Good career move.
How did you do that ?
PID adjustment, or custom programming ?