Airplane weight with fuel and passengers. Automatic CG?

[Vantskruv]

I'm wondering if this is implemented, or maybe it is not noticable?

 

I.e. let us say you will have about 140 passengers with bags. You may self calculate the total weight, and placement of passengers (maybe a 3rd party tool will come out for this; I don't expect random passenger seating of passengers that will be generated with this airplane, correct me if I'm wrong, but it would be nice with a such tool ).

 

With this information you may calculate the required fuel depending on winds, height, distance and weight. Also you may calculate the required TRIM for takeoff.

 

Now to the real question, will you implement automatic influence of the aircraft CG depending on fuel and passenger seating?

 

Will this be automagically changed while fuel is expended while flying?

[Litjan]

Yes, CG will change as fuel burns. For passenger seating, we assume an average spread throughout the cabin, at least when you load the aircraft. But if you want to pretend that only half the seats are occupied, and everyone sits in the rear, you can. Just calculate the CG (taking a third-party-tool, for example), and then enter this CG with our "ground services menu". The airplane´s CG will be adjusted accordingly.

 

In other words - you supply the weight and the CG, the airplane flies accordingly (including fuel burn).

 

Jan

[Vantskruv]

Yet I don't think any third party tools are there.

If I get some time, maybe I come up with something.

 

Though I need some basic information as where the CG point (using it as a datum to get the correct offset for X-Plane Weight and Balance) is stations for the seatings and cargo from the datum/CG point.

 

EDIT: What I mean with CG point is the X-Plane CG point, so you get the calculations correct. Sorry if I am so fidley.

 

EDIT2: It would be nice to know of LEMAC and MAC too.

Edited January 9, 2016 by Vantskruv

[Morten]

The CG envelope is between 48,4 - 51,3 feet from the nose.  CG for ACN calculations is at 50,2

This again converted to MAC is between 4-30% and 20%

 

So transfer this to a seatmap, and you have good start

 

M

Edited January 9, 2016 by Morten

[Eddie]

This honestly seems like a whole bunch of extra unnecessary work for end users compared to other products. We're not asking to set individual passengers in seats or anything, but a "passenger number" and "cargo weight" slider that gives you a CG and ZFW would be more than enough.

[Vantskruv]

For sure it is overkill for just flying. But it gets a little more immersible if you have a passenger and cargo generator for every flight affecting the CG. I guess this will be more of a impact for smaller airplanes. I'm not sure about the big aeroplanes as the 737.

 

A vision of mine is to make a plugin which randomly generates the load of passengers and cargo, easily customized by users for different aircrafts (seatmap with STA data and BOW CG is only required).

Also it should be possible to assign the number of passengers yourself. I.e. simbrief is randomizing the number of passengers and cargo onboard, so user may put in the data, and the plugin automagically sets the CG in X-Plane for the ZFW.

 

I think the maths behind is not too complicated, and programming it is not to complicated either. The only effort here is to get the seatmaps and the airplane BOW CG (which you can get via planemaker easy).

 

Right now it is very hard to find the the seatmap for the 737 that IXEG is making...

[tkyler]

We're not opposed to these types of tools / features or stuff, its just a matter of not knowing if/when we'll get to it.  Of course we want it all.

 

This honestly seems like a whole bunch of extra unnecessary work for end users compared to other products

 

And compared to other products,  we have a whole lot of essential features they don't have.    Between a CG/seat thingamajig and a FMS that doesnt' give me "invalid entry' for every other button press....I'll take the FMS.  The CG/seat feature can wait.

Edited January 9, 2016 by tkyler

[niebieski]

This honestly seems like a whole bunch of extra unnecessary work for end users compared to other products.

 

I hope that we - X-Plane community - stop thinking this way in the near future.

Since i switched from FS franchise to X-Plane years ago i'm missing a PROPER airliner that could replace my favourite FS addons (PMDG, Leonardo, RFP ...).

With all respect, FlightFactor and JarDesign offerings would appeal to very limited audience in the FS community. For bugs and lack of detail (INVALID ENTRY on the FMC as Tom said is very common, EGT values on engine startup, autopilot logic and a whole lot of details most X-Plane users don't notice or don't care about).

I sincerely hope that IXEG will change this.

[Vantskruv]

But give me some data and I will look in to it!

 

Of course you don't need to add extra features, I think it is enough as it is if the hype turns out well!

[tkyler]

Of course you don't need to add extra features, I think it is enough as it is if the hype turns out well!

 

 

 

And TBH...I'm looking forward to adding more features.   It won't end with release, I assure you

 

-tkyler

[Eddie]

 

I hope that we - X-Plane community - stop thinking this way in the near future.

PMDG features this "passenger/cargo" load mechanism in their MCDU menu, too. IXEG is pretty much the only major developer that doesn't, it seems.

[Morten]

PMDG features this "passenger/cargo" load mechanism in their MCDU menu, too. IXEG is pretty much the only major developer that doesn't, it seems.

 

We also have alot of features that nobody else have  Seriously, it is not very hard to make, but at the moment we

have set a list of set target functions for v1.0 and a target (internal) release date, so our focus is that list until after release.

After that it's time for us to start working on those "nice to have" lists and "gaming" aspects.

[tkyler]

PMDG features this "passenger/cargo" load mechanism in their MCDU menu, too. IXEG is pretty much the only major developer that doesn't, it seems.

 

 

PMDG been in business what?  18 years?    We've had weather radar since day 1....they just got it into the NGX when?   several years after release?  Other major manufactures...you can't even "lift" the flap lever out of a gate........Do you really want to have a pissing contest over "feature X" or feature Y"?   We'll be here all year.  Noted that you like that feature and you want it.

 

-tkyler

[rokisk8]

RELEASE DATE PLEASE!!!!!!!!!!!!!

[KDN77RUS]

RELEASE DATE PLEASE!!!!!!!!!!!!!

What about the intrigue?

[Ben Russell]

RELEASE DATE PLEASE!!!!!!!!!!!!!

 

..even the smallest hint of a release date results in users being unhappy and complaining if they feel their expectations are not being met.

 

See here, for a recent example;

http://forums.x-plane.org/index.php?showtopic=92465&hl=

 

 

This is why we don't publish them.

Edited January 9, 2016 by Ben Russell

[Eddie]

We also have alot of features that nobody else have  Seriously, it is not very hard to make, but at the moment we

have set a list of set target functions for v1.0 and a target (internal) release date, so our focus is that list until after release.

After that it's time for us to start working on those "nice to have" lists and "gaming" aspects.

That's understandable, but the tone in the "v1.0 feature list" was more along the lines of "we think 'cute interfaces for setting passenger loads are useless" and less "we'll look at getting it out after release. If it's the latter, I don't have an issue.

 

PMDG been in business what?  18 years?    We've had weather radar since day 1....they just got it into the NGX when?   several years after release?  Other major manufactures...you can't even "lift" the flap lever out of a gate........Do you really want to have a pissing contest over "feature X" or feature Y"?   We'll be here all year.  Noted that you like that feature and you want it.

 

-tkyler

 

The intent was not to have a "pissing contest", but rather to address that user's comment that the "soft sims" are the only ones with passenger loaders. I merely pointed out another study sim with that feature.

[tkyler]

I'm a big fan of providing all of those conveniences Eddie, in their proper order and time.   We just want folks to understand that we are drawing a line as to what goes in at the onset due to time constraints.  We'll look into such options in due course.

 

-tkyler

[Eddie]

I'm a big fan of providing all of those conveniences Eddie, in their proper order and time.   We just want folks to understand that we are drawing a line as to what goes in at the onset due to time constraints.  We'll look into such options in due course.

 

-tkyler

Understood, thanks for the clarification.

[dr_nerdrage]

Yes, CG will change as fuel burns. For passenger seating, we assume an average spread throughout the cabin, at least when you load the aircraft. But if you want to pretend that only half the seats are occupied, and everyone sits in the rear, you can. Just calculate the CG (taking a third-party-tool, for example), and then enter this CG with our "ground services menu". The airplane´s CG will be adjusted accordingly.

 

In other words - you supply the weight and the CG, the airplane flies accordingly (including fuel burn).

 

Jan

 

Could we get a preview of said ground services menu? If it's in one of the videos, I may have missed it.

[Cameron]

Could we get a preview of said ground services menu? If it's in one of the videos, I may have missed it.

Please note this is considered work in progress at all times for now...

 

(Click for larger image)

 

[Litjan]

Could we get a preview of said ground services menu? If it's in one of the videos, I may have missed it.

 

You obviously did. Didn´t watch the videos closely enough! Bad Dr. Nerdrage!

 

Start at 02:00 mins, if you are the impatient type

 

 

Here is my stance on setting the CG and Weight: When we initially conceived this aircraft, we had the serious simulation user in mind. The guy who wants to experience what the real pilot experiences. This explains why we handle the CG and weight stuff the way we do. Let me tell you what part the pilot has in determining and setting weight and CG.

 

The pilot gets an estimated zero-fuel-weight on his electronic flight plan. Together with his First Officer he reviews all flight parameters, and if he works for a decent airline that care for the life of their passengers, and not only their money, he gets to determine how much fuel (in excess of the legally required minimum) he takes. Obviously he can´t overload the aircraft, and sometimes you have to make a call between taking more fuel and leaving payload behind.

 

Once the loading is completed (and no, the Captain doesn´t tell every passenger where he needs to sit), he gets a printout of the electronic load-sheet. A bunch of numbers, along with the actual Zero Fuel weight, and the CG. He punches those into the FMS and thats it.

 

No clicking on seats. No sliding bars to fill cargo holds. No neat little represenation of load and trim envelope, moving CG´s or stuff like that. Now we know that you guys dig that stuff, though, and we might get to it later, for now this first release is favouring virtual pilots, not the virtual loadmasters.

 

Jan

[niebieski]

PMDG features this "passenger/cargo" load mechanism in their MCDU menu, too. IXEG is pretty much the only major developer that doesn't, it seems.

 

Eddie,

 

I wonder what is so special about being able to load your plane via MCDU? What's it got to do with realism?

And how is IXEG different in this aspect from other X-Plane developers? Can you name any X-Plane airliner that does indeed have MCDU airplane load feature? I can't seem to recall any at the moment.

 

MCDU loading is a just a way of interacting with the sim user to load the airplane. I very much prefer to have a simple interface that Cameron showed us couple of posts ago* and put the data from the loadsheet into the MCDU myself (that's how you do it in real life).

 

* having number of PAX shown in the ground services menu would be handy for flight plan filing purposes (online flying)

[tkyler]

I wonder what is so special about being able to load your plane via MCDU? What's it got to do with realism?

 

 

I'll venture a bit of a guess Radek......    Of course this is "entertainment" and what entertains one is certainly diversified amongst simmers.  Given the fact that we are generally limited to a chair and a screen,  I think it reasonable that the more cognitive stimulation one can get, the better.   Further, given that the stimulation is manifested through "on screen interaction", then the more actions one can do in the sim, the more entertaining it CAN be for some.   Flight simmers seem to be in a class of people my wife likes to calls, "button pushers".  We like gadgets and complexity and flashing light thingys.   By adding these other tasks, i.e. "loadmaster or flight dispatcher, to the sim, we essentially increase the amount of cognitive challenges you can engage in. (conveniently through button pushing )   The problem is the aforementioned diversification of simmers...where what is good enough to stimulate one person given the whole of the product isn't good enough to stimulate another.  The solution is to "have it all", but in doing so, we run the risk of over complication and when you get cognitive saturation due to complexity.....then that is akin to a stall.   So where is the balance?  Well...its currently in the IXEG team members comfort zone .  We hope enough folks share it to enjoy it.  BUT for those wanting more....I will say that the team's comfort zone (and feature set) will expand with time....but we will still ask the question for any given feature, "does Feature X belong in our realm of responsibility to simulate given our target goals with the simulation?"  Only time will tell what our answers will be.    Though there are many aspects to the simulation of flight and flight operations (a valid hobby X-Plane has the capacity to fill)....OUR product squarely targets 737-300 aircraft operations from the captains perspective at the moment.  A more generic "loadmaster / flight dispatch" type of plug-in might be a good product in its own right.

 

-tkyler

Edited January 10, 2016 by tkyler

[Javier]

  X-Dispatcher 10   would be a nice sim but for now I´m only interested in 737-300 for X-plane