How To Calculate Weight And Balance

Airplanes are complex machines that require constant maintenance. They also carry passengers, cargo, mail, and other items. In order to ensure safety, airlines have strict rules regarding weight and balance.

How To Calculate Weight And Balance

To calculate the weight of a plane, multiply its length by width by height. The total weight should never exceed the maximum allowed weight.

To check if the aircraft is in balance, you need to measure its center of gravity (CG). This will be located somewhere between the wings or tail. If it’s too far forward or rearward, it means the plane needs balancing.

Aircraft Can Be Balanced With Different Methods

1) By using an external device called a “balance bar”. It consists of two metal bars attached to the fuselage at each end. The CG is placed on one side of the plane and the other side is weighed down.

Then the plane is lifted until both sides are level. Once this has been achieved, the plane is well-balanced.

2) Using an internal method called “aircraft static stability” which measures the forces acting on the plane. These include lift, drag, thrust, weight, etc.

3) With a combination of the above methods. For example, you could use an external device to weigh the plane down and then use the internal method to determine how much weight must be added to the opposite wing to achieve equilibrium.

What You Need To Weigh In

If your plane is too light, you may need to add more fuel to make up for the extra weight. However, if the plane is too heavy, it won’t be able to fly as fast as it would otherwise.

The following tools are used for calculating the weight and balance of a plane: 

• Three accurate scales for each wheel.

• Ramps to get your plane onto the scales. 

• A calculator to calculate the numbers. 


You’ll need to prepare the plane before weighing it. First, remove any objects from inside the cockpit and the rest of the plane.

Next, turn off all electrical devices, including radios and lights. Finally, clean the outside of the plane, so there are no obstructions.

Step 1 – Measure The Length, Width & Height

Measure the length, width, and height of your plane. Multiply these three numbers together to get the volume of the plane.

Step 2 – Calculate The Center Of Gravity

Now find the CG of your plane. It’s usually located somewhere between the wings. The CG is calculated by multiplying the length of the plane by 0.5, the width by 0.5, and the height by 0.5.

Step 3 – Find The Maximum Allowable Weight

Find the maximum allowable weight of your plane by adding the gross weight plus the empty weight of the plane.

Gross weight is the total weight of the plane without passengers, cargo, mail, or anything else. Empty weight is the weight of the plane minus everything except the engines.

Step 4 – Check The Aircraft Static Stability

Now that you know the maximum allowable weight, you can check the aircraft’s static stability. This involves measuring the forces acting on the airplane.

These include lift, thrust, drag, weight, etc. If the plane is not stable, you’ll have to add some weight to the opposite wing.

Step 5 – Add Fuel

Once you’ve determined the correct amount of weight to add to the plane, you’ll need to calculate how much fuel you’ll need to add to compensate.

To do this, multiply the total weight of the aircraft by the percentage of fuel needed to bring the plane back to full power.

Step 6 – Prepare Your Plane

Before you start adding weight to the plane, you should first prepare it. Remove any items that might interfere with your balance bar measurements. Also, ensure that the engine is running smoothly.

Step 7 – Place The Balance Bar

Place the balance bar into the center of the fuselage. Make sure that the balance bar is parallel to the ground.

Step 8 – Determine How Much Weight Needs Adding

Now that you have the balance bar set up, you’re ready to begin adding weight. Start by placing one end of the balance bar onto the floor. Then place the other end on top of the wing.

Once you’ve done this, you’ll need to subtract the weight of the plane from the balance bar. Take note of where the plane weighs most heavily. You want to add weight to that area.

Enter The Data

You should have a weight and balance spreadsheet. Enter the data for each side of the plane.

The weight of the plane will be entered as “Gross” and the weight of the added weight will be entered as “Weight.”


If the plane has a gross weight of 1000 lbs, and you add 100 lbs of weight, then enter “1000” for the gross weight and “100” for the weight.

If the plane has a net weight of 900 lbs, you would enter “900” for the gross weight.

Note: When entering weights, always use pounds (lb) or kilograms (kg). Do not use ounces (oz), grams (g), or milligrams (mg).

When calculating the weight of the plane, remember to take into account the weight of the wings, tail, and control surfaces.

Tip: If you don’t know what weight is on an airplane, you can get an approximate value using the following formula:

(Total Weight / Total Length x 0.5) + Wing Area * 0.25 + Tail Area * 0.125

For example, if you had a plane with a length of 200 feet and a total weight of 2000 lbs, then the wing area would be about 70 square feet.

The tail area would be around 20 square feet. Using these numbers, we’d arrive at a weight of approximately 2200 lbs.

Final Thoughts 

To conclude, weight and balance calculations are important because they help pilots determine whether their planes are safe to fly.

It’s also helpful when planning flights because it allows them to make decisions regarding which routes to take.

Calculating the weight and balance properly will ensure the pilot and crew are seating passengers accordingly. 

All pilots and crew must do this before a flight in order to ensure they are flying in the safest manner. 

Jacob Stern
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