content_image/567744.jpg content_image/567765.jpg content_image/567748.jpg content_image/567761.jpg content_image/567759.jpg content_image/567763.jpg content_image/567753.jpg
<img src='content_image/567744.jpg'>

The change of CG is added to (or subtracted from when appropriate) the original CG to determine the new CG: 77 + 1.5 = 78.5 inches aft of datum 

The shifting weight proportion formula can also be used to determine how much weight must be shifted to achieve a particular shift of the CG. The following problem illustrates a solution of this type. 

## Given: 

<img src='content_image/567765.jpg'>

Determine how much cargo must be shifted from the aft cargo compart- ment at station 150 to the forward cargo compartment at station 30 to move the CG to exactly the aft limit. 

## Solution: 

<img src='content_image/567748.jpg'>

A simpler solution may be obtained by using a computer or calculator and a proportional formula. This can be done because the CG will shift a distance that is proportional to the distance the weight is shifted. 

## Weight Addition or Removal 

In many instances, the weight and balance of the aircraft will be changed by the addition or removal of weight. When this happens, a new CG must be calculated and checked against the limitations to see if the location is acceptable. This type of weight and balance problem is commonly encountered when the aircraft burns fuel in flight, thereby reducing the weight located at the fuel tanks. Most small aircraft are designed with the fuel tanks positioned close to the CG; therefore, the consumption of fuel does not affect the CG to any great extent. 

The addition or removal of cargo presents a CG change problem that must be calculated before flight. The problem may always be solved by calculations involving total moments. A typical problem may involve the calculation of a new CG for an aircraft which, when loaded and ready for flight, receives some additional cargo or passengers just before departure time. 

Example 

Example 

## GivGLYPH<df00>n: 

<img src='content_image/567761.jpg'>

DGLYPH<df00>tGLYPH<df00>rminGLYPH<df00> thGLYPH<df00> location of thGLYPH<df00> CG if 140 pounds of baggagGLYPH<df00> is addGLYPH<df00>d to station 150. 

## Solution: 

<img src='content_image/567759.jpg'>

Add ∆CG to old CG 

NGLYPH<df00>w CG = 80 in + 1.4 in = 81.4 in 

## GivGLYPH<df00>n: 

<img src='content_image/567763.jpg'>

DGLYPH<df00>tGLYPH<df00>rminGLYPH<df00> thGLYPH<df00> location of thGLYPH<df00> CG if 100 pounds is rGLYPH<df00>movGLYPH<df00>d from station 150. 

## Solution: 

<img src='content_image/567753.jpg'>

Subtract ∆CG from old CG 

NGLYPH<df00>w CG = 80 in − 1.2 in = 78.8 in 

In the previous examples, the r CG is either added or subtracted from the old CG. Deciding which to accomplish is best handled by mentally calculating which way the CG will shift for the particular weight change. If the CG is shifting aft, the r CG is added to the old CG; if the CG is shifting forward, the r CG is subtracted from the old CG. 

## Chapter Summary 

Operating an aircraft within the weight and balance limits is critical to flight safety. Pilots must ensure that the CG is and remains within approved limits throughout all phases of a flight. For additional information on weight, balance, CG, and aircraft stability refer to the FAA handbook appropriate to the specific aircraft category. 

Example 

Example 

