Dear All,

 

The J41 FMC has another BUG.

 

In my previous post User Defined Waypoont are missed by the AP, due to a problem in the calculation of the Latitude and Longitude coordinates by the FMC.

 

In addition, Offset Waypoints do not work.

 

For example, I entered an Offset Waypoint:

 

Parent Waypoint: KFHR

Radial: 120 Degrees

Distance: 16 NM

 

The LAT/LON for the Offset WPT thrown by the FMC is: N48 19 28 and W122 45 14 which is wrong.

 

Please see the right Lat/Lon calculation at

 

http://www.movable-type.co.uk/scripts/latlong.html

 

Basically, the FMC has a serious BUG.

 

I have submitted several tickets and the team is trying to contact the Developer who coded the FMC but no luck.

 

Can someone in PMDG help me?

 

Thanks

 

Federico Sucari

Ain't happenin' buddy unfortunately. I can't see 'em tearin' apart the existing FMC code to fix this, especially with newer releases and development taking up a lot of their time.

 

I've never even tried offset waypoints within the XLS...I'm quite surprised it even accepted it.

 

Having said that...are you sure you are entering it correctly? Is the web-page link take into account magnetic deviation? Is the calculation based on true north? Are you figuring out your radians correctly?

Yeah, I hate to pull the card I normally pull, but the JS4100 was a light product testbed for the NGX. While it has a simple failure model, it doesn't have the failures model their other aircraft have. In a similar vein, the FMC isn't fully-featured, which you can see by the INOP HOLD feature (forces you to bust out the dusty IR skills, which is nice sometimes).

 

So, while I can understand it's frustrating that some features do not work, or don't work correctly, it's still a great aircraft. Suffice it to say, as a product that's now 3 or 4 years old, I think we can stop trying to point out flaws and just enjoy flying it.

I think we can stop trying to point out flaws and just enjoy flying it.

 

There is nothing wrong with pointing out a limitation; and by asking questions and raising some discussion we might even be able to figure it out, or come up with a work around. I'm thankful that someone took the time to let me know there is a problem so I don't pull my hair out.

There is nothing wrong with pointing out a limitation;

 

Never said there was. Note how you phrased it and how the thread title differs. There's a difference between informational and accusatory speech. I can't stand for the latter.

Never said there was. Note how you phrased it and how the thread title differs. There's a difference between informational and accusatory speech. I can't stand for the latter.

 

Actually, I'm pretty sure you did. "stop trying to point out flaws"

 

And saying that you found a bug is not accusing anyone of anything; bugs are usually accidents. The OP is asking for help. If its not a bug, then someone can point that out.

Actually, I'm pretty sure you did. "stop trying to point out flaws"

 

I said "Suffice it to say, as a product that's now 3 or 4 years old, I think we can stop trying to point out flaws and just enjoy flying it." Please don't put words in my mouth or quote out of context. Note the 'we'. The way I said it is more suggestive of the idea that we can come to an understanding as a group that it's better to just enjoy it than try to nitpick faults. I said quite a lot more than simply "stop pointing out flaws."

 

What I didn't say, however, is "stop pointing out limitations."

 

My point was that the thread title is "J41 FMC Another BUG," which is not so much to say "hey, I found something that needs to be investigated," it's more to say "hey, there's a problem with your program."

 

As someone who used to teach computer classes, I found that the vast majority of the times participants said "I'm doing it exactly like I'm supposed to and it's not working!!!" it was a PBKAC issue. Now, knowing the FMC isn't fully featured, it could very well just be that its implementation is incorrect, but there's a vast issue between:

J41 FMC Another BUG

and

J41 FMC Offset Waypoint Issue

 

One suggests it's all the fault of one party, while the other just states there is a problem.

I said "Suffice it to say, as a product that's now 3 or 4 years old, I think we can stop trying to point out flaws and just enjoy flying it." Please don't put words in my mouth or quote out of context. Note the 'we'. The way I said it is more suggestive of the idea that we can come to an understanding as a group that it's better to just enjoy it than try to nitpick faults. I said quite a lot more than simply "stop pointing out flaws."

 

What I didn't say, however, is "stop pointing out limitations."

 

My point was that the thread title is "J41 FMC Another BUG," which is not so much to say "hey, I found something that needs to be investigated," it's more to say "hey, there's a problem with your program."

 

As someone who used to teach computer classes, I found that the vast majority of the times participants said "I'm doing it exactly like I'm supposed to and it's not working!!!" it was a PBKAC issue. Now, knowing the FMC isn't fully featured, it could very well just be that its implementation is incorrect, but there's a vast issue between:

J41 FMC Another BUG

and

J41 FMC Offset Waypoint Issue

 

One suggests it's all the fault of one party, while the other just states there is a problem.

 

I didn't interpert this post as offensive, perhaps its your interpretation and you're nitpicking fault. Do you know if Federico's primary language is English? I certainly don't know, so I'm not going to really pay much attention to the wording.

 

If I think I found a bug, I would point it out, and open a ticket because I don't believe there are any time limits; and wether you think the product I paid for doesn't warrent any support or discussion because its 4 years old, is irrelevant. If the intent was to not implement the functionality, then PMDG can clarify; thats part of support. The answer doesn't have to be "ok, we'll fix it". But anyone intereseted should still ask. Maybe they will look at it; nothing wrong with making great addons greater.

When I take lat/lon for KFHR from the web (48 31 19N,123 1 27W), and compare it to the output you say the FMC is reporting, the site you mention gives a distance of 29.7km on a bearing of 137.8 degrees. This is what you say is "another BUG", "wrong" and "a serious BUG".

 

Which is pretty odd really. 29.7km is 16Nm, 137.8 minus the current magnetic variation of 18.1 gives an answer pretty close to your stated 120 degrees. Of course if you work with the magnetic variation that FSX actually uses instead of the real world value, and also use the coordinates from your navigation database instead of the web, the answer will probably be closer still.

 

Next please.

Myself and Ernie (the J41 FMS dev) both tested the previously claimed "bug" by this individual and saw nothing wrong on our machines. We are not at all convinced that the things this person is finding are legitimate issues.

 

The idea that we won't fix things in the J41 is bogus too - we've fixed multiple CTDs, Navdata issues, an issue with one of the 2D popups etc since SP1 was released and anyone who writes in about one of the issues gets a new gauge from us that fixes that stuff.