RV-7 N890GF

Weight and Balance Application Latest Release

I completed a full weight and balance on the plane. I did it using a method I read about online where you just need to weigh the main gear in a level attitude but not the tail. This makes it easier, as weighing the tail in level attitude is a bit annoying.

The Empty Weight came out at 1055.84 lbs. The Right Main at 478.13 lbs. Left Main at 474.32 lbs. and the Tail at 103.41 lbs.

Next is to weigh the Main gear in a level attitude. So I leveled the plane and re-weighed the main gear, which came out to 488.59 lbs for the Left main, and 491. 80 lbs for the right main. Then you subtract the Main gear total (sum of the above two weights) from the empty weight and that gives you the tail wheel in a level attitude, which was 75.45 lbs. These numbers are then used for all the W&B calculations.

I used the standard Vans Aircraft suggested datum of 70″ forward of the leading edge of the wing, and the station values for all the weights are calculated from that.

Once I calculated the Empty weight, I used a python program I made to calculate all the other configurations.

Above is a screenshot of the first flight configuration in my tool. I also calculated max weight, aft CG, aerobatic CG and full forward CG.

With how the Empty Weight came out, I will be a bit limited in how much baggage I can hold if I have full fuel and a passenger. The lightweight composite MT propeller and the lightweight EarthX battery have reduced the weight on the nose quite a bit it seems. We’ll see if I need to add weight to the nose at some point in the future if I need to shift the CG forward (I do have a lightweight tailwheel on order, but will wait to change anything before the first flight).