G3X Touch W/B for FX-3

[Andy]

The FX-3 AFM template includes this statement -

"NOTEThe Garmin G3X Touch Weight and Balance feature is
not compatible with this aircraft."

Can someone please explain why? What is unique about the FX-3 that would prevent the normally simple math of mass, arm, and moment being computed in the Garmin GDU.

Thanks,
Andy

[Andrew Y]

Hello Andy,

I think that may be a carry over statement. It's not the computation of arm and moment that was the issue. It's the display of the allowed envelope. From when we first started using the Garmin G3X, it only provided a rectangular W&B envelope. The forward limit, aft limit, and max gross weight were the only allowed entries. Our Cubs have a sloped line at the upper forward corner. The AFM template was created that highlighted that incompatibility. One of the fairly recent G3X software updates allowed a more complicated shape of the W&B envelope. Feel free to use the G3X W&B feature if you can configure it to work, and discard that statement from the AFM template.

Hope this helps,
Andrew

[Andy]

Thanks Andrew. I suspected it was the envelope that was the issue but there is nothing unusual about the FX-3 envelope. The envelope for the very common PA-28 is a similar shape.

Good to know that Garmin has revised the envelope depiction because the mass/arm envelope would be useless for lots of airplanes, not just FX-3, if it was limited to being a rectangle.

Andy

[chipallen]

I set up the W&B in the G3X on my new EX-3 and it works just fine; CG envelope looks just like the POH, so it can certainly be done.

[Andy]

I set up the W&B in the G3X on my new EX-3 and it works just fine; CG envelope looks just like the POH, so it can certainly be done.

Thanks for confirming it can be done.

I hope CubCrafters will remove the outdated note from the AFM template and will deliver aircraft with the W/B configured correctly for the FX-3.

Andy

[Pete D]

Thanks for confirming it can be done.

I hope CubCrafters will remove the outdated note from the AFM template and will deliver aircraft with the W/B configured correctly for the FX-3.

Andy

All current production a/c are shipped with the w&b envelope configured per the POH. Empty weight and C.G. should also be correct for that specific aircraft, however you should double check it as sometimes aftermarket or post delivery changes have been done to the airplane and the G3X doesn't get updated when the official w&b in section 6 of the POH is updated. This is especially true of new to you used a/c.

Pete D.

[Andy]

however you should double check it as sometimes aftermarket or post delivery changes have been done to the airplane and the G3X doesn't get updated when the official w&b in section 6 of the POH is updated.
Pete D.

Thanks Pete. I'm only a few weeks away from taking delivery and I'll add that to the list of items to check.

Andy

[Andy]

All current production a/c are shipped with the w&b envelope configured per the POH. Empty weight and C.G. should also be correct for that specific aircraft, however you should double check it as sometimes aftermarket or post delivery changes have been done to the airplane and the G3X doesn't get updated when the official w&b in section 6 of the POH is updated. This is especially true of new to you used a/c.

Pete D.

I can confirm that my new airplane did have the weight and balance data loaded and did depict the correct envelope. However, my AFM Section 9.6 still includes "Note - The Garmin G3X Touch Weight and Balance feature is not compatible with this aircraft".

Andy

[Andy]

I updated my FX-3 G3X W/B to account for an added Garmin G5. Before I changed anything the W/B configuration showed empty weight and arm equal to the most recent CubCrafters information in the AFM W/B table. This empty weight includes 5 gallons of unusable fuel.

However, the W/B fuel configuration showed maximum fuel limited to 44 gallons. Shouldn't the W/B fuel entry be limited to the usable fuel quantity of 39 gallons?

On the other hand, the fuel computer is limited to 39 gallons even if added fuel + indicated fuel remaining exceeds 39 gallons.

I'm left wondering how best to configure the fuel computer and the W/B computer to properly account for unusable fuel.

Andy

[Andy]

I updated my FX-3 G3X W/B to account for an added Garmin G5. Before I changed anything the W/B configuration showed empty weight and arm equal to the most recent CubCrafters information in the AFM W/B table. This empty weight includes 5 gallons of unusable fuel.

However, the W/B fuel configuration showed maximum fuel limited to 44 gallons. Shouldn't the W/B fuel entry be limited to the usable fuel quantity of 39 gallons?

On the other hand, the fuel computer is limited to 39 gallons even if added fuel + indicated fuel remaining exceeds 39 gallons.

I'm left wondering how best to configure the fuel computer and the W/B computer to properly account for unusable fuel.

Andy

No answers here but, months ago, I decided the factory configuration was wrong and changed the W/B fuel limit to 39 gals. Don't know if CubCrafters ever fixed this for new deliveries.