Weight and Balance G3

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MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Weight and Balance G3

Post by MikeBlackburn »

Hi
does anyone know how to set a weight and balance range taking into account fuel burn?

In the W/B it will give you Mass (in white), Empty mass and full mass - all are the same.
Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
rainier
Site Admin
Posts: 662
Joined: Fri Aug 28, 2020 7:03 pm

Re: Weight and Balance G3

Post by rainier »

https://www.youtube.com/watch?v=whqPWRWOrAA&t=107s

This is a video made by avid MGL user Dutchroll. This should explain how it works. It's a little more involved but quite powerful.
MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Re: Weight and Balance G3

Post by MikeBlackburn »

Thanks - I have watched that - when Dutchroll is doing the W/B for the RV-7 he has en empty and a full weight and the current weight on the weight and balance popup.

When he does it for the Pitts - all the numbers are the same again.
I thought there would be a menu setting to set max t/o and empty weights but if there are I can't find them....
Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
dutchroll
Posts: 6
Joined: Thu Sep 17, 2020 6:53 am

Re: Weight and Balance G3

Post by dutchroll »

There's actually no menu setting for these numbers. They can only be pre-defined in the "wb.def" file and any changes would require the creation of a new wb.def file in the simulator and uploading that to the EFIS.

When you create that file using the weight & balance function in the EFIS simulator/designer, there is a box near the top left to enter your empty weight. That's the only place you can define it. The MTOW is treated slightly differently because it's a limitation, and must be entered as a "definition" in the table at bottom left so that it appears as a limiting point on your graph.
MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Re: Weight and Balance G3

Post by MikeBlackburn »

Thanks @dutchroll

I get all of that - what I can't understand is that in my simulator, When I bring up the weight and balance I only see one cross on the graph - the green 'full ms/fullCG' one, whereas on your video you definitely had a white, red and green cross - i.e I need to see the C/G range for a given load..
have attached a image to show what my setup is - I'm sure I'm doing it wrong somehow...
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Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
dutchroll
Posts: 6
Joined: Thu Sep 17, 2020 6:53 am

Re: Weight and Balance G3

Post by dutchroll »

Ah ok this seems to depend on whether your fuel tank selection is a virtual tank (you just get a display of the current CofG) or a "sensed" fuel tank, where you get the other crosses.

My Pitts actually has only a virtual tank - fuel remaining is calculated by fuel flow in the EFIS and I just have the single "x" depending on what fuel value I manually enter. The example I did, which was an RV, had actual sensed fuel selections in the setup.

Interestingly I just altered the tank selection from virtual to sensed in the w&b setup in the G3 sim (after which it displayed the red and green "x"), then tried to alter it back to what I had, and it keeps locking up! There's some odd buggy behaviour there.
MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Re: Weight and Balance G3

Post by MikeBlackburn »

SO this would actually be a great feature for @rainier to add - have a defined zero fuel weight for the entered load oad to generate the full fuel to empty fuel C/G range...
Would this be possible do you think?
Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
rainier
Site Admin
Posts: 662
Joined: Fri Aug 28, 2020 7:03 pm

Re: Weight and Balance G3

Post by rainier »

That's what the thing does.
You define a station as fuel. It then calculates the position of your cross based on fuel load. Similar for baggage etc.
It needs physical fuel tanks for that. Virtual tanks are not counted.
MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Re: Weight and Balance G3

Post by MikeBlackburn »

dutchroll wrote: Thu Oct 08, 2020 9:08 am Ah ok this seems to depend on whether your fuel tank selection is a virtual tank (you just get a display of the current CofG) or a "sensed" fuel tank, where you get the other crosses.

My Pitts actually has only a virtual tank - fuel remaining is calculated by fuel flow in the EFIS and I just have the single "x" depending on what fuel value I manually enter. The example I did, which was an RV, had actual sensed fuel selections in the setup.

Interestingly I just altered the tank selection from virtual to sensed in the w&b setup in the G3 sim (after which it displayed the red and green "x"), then tried to alter it back to what I had, and it keeps locking up! There's some odd buggy behaviour there.
Also... the sensed level is useful if you don’t have wing tank sensors like mine that read 50l max due to the dihedral despite there being room for 80litres.
Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
MikeBlackburn
Posts: 28
Joined: Mon Oct 05, 2020 7:14 am

Re: Weight and Balance G3

Post by MikeBlackburn »

rainier wrote: Thu Oct 08, 2020 1:18 pm That's what the thing does.
You define a station as fuel. It then calculates the position of your cross based on fuel load. Similar for baggage etc.
It needs physical fuel tanks for that. Virtual tanks are not counted.
Yes but would it be useful or possible to ignore the fuel load and do a W/B position for that to give an indication of possible landing C/G? Although I guess there is nothing stopping one from doing it near top of descent... Just with the sling 4 you can get out of C/G with low fuel levels if the rear seats are occupied.... Again... just something that would be nice to have but probably not possible or useful for the majority?
Mike Blackburn
MGL iEFIS G3
ZU-IBM (Sling 4 Turbo S/n 009)
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