Weight and Balance

TLDR

• Conducted the weight and balance

Details

I completed the weight and balance of the airplane today. The process is pretty straightforward:

• Prepare the weight & balance sheet
• Drain the fuel from airplane
• Make sure all permanent parts are on the airplane
• Push it to the scale
• Read the numbers
• Plug in the numbers to the weight & balance sheet and get the empty weight CG

Preparation

Template

On the W&B template preparation, I chose to use the W&B from EAA. The sheet is designed for tail draggers and it’s missing a few things that I need (for example baggage extension). So I took a picture and fed it into Claude Code to generate a Google Doc editable version. Then I customized it to work for my airplane (tricycle gear and has additional baggage extension compartment).

In case anyone is interested in the template, here it is.

Getting the Airplane to Final Weight

On the airplane itself, I removed all the building tools & chocks from the baggage compartment, and drained the fuel from both tanks through the drain port. I did not care to drain the tank to the last drop. After the fuel was drained from the draining port, some were still left in the tank as unusable fuel.

Leveling the Airplane

To weight the airplane, it must be level to the ground. According to the maintenance manual, the level is found by making sure the row of rivet directly below the canopy door is level to the ground.

So I set up a laser level to shoot a line of red beam towards the row of rivets. The airplane was already almost level, with the nose slightly high. I deflated the front tyre just a little, and the red level laser beam showed the rivet row was perfectly level.

Setting the Scale

Then, I set the 3 scales in front of each wheel. On the 2 main wheels, I put a ramp next to the scale.

With a tow bar, I pulled the airplane’s two main wheels onto the scale pretty easily.

Then I had to get the last scale under the nose wheel. Normally a second person can help push the tail down and I can just put the scale under the nose wheel. Unfortunately I didn’t have any helper today. So I just tied a piece of long string to the scale so I can pull the string to move the scale at the back of the airplane.

I then pushed the tail down. While having the tail still pushed down, I pulled the string to drag the scale under the nose wheel. This sounds pretty difficult but it’s actually very easy to accomplish.

Weighing

The weighing it’s just reading numbers. I waited the scales to stabilize, then took pictures of the number from each scale.

Calculating

In total, the airplane weighed 1220 lbs, with a CG at 73.7 inches. It’s heavier than I thought, but well within the CG envelop.