Weight And Balance

Question 1

Effects of adverse balance

Answer 1

Stability

Control

Question 2

Negligible weight / CG change

Answer 2

1lbs or less for <5000lbs
2lbs or less for 5000-50000lbs
5lbs or less for 50000lbs+
CG change less than 0.05%.of mean aerodynamic chord (MAC) = average distance from leading edge to trailing edge

Question 3

Moment arm

Answer 3

Horizontal distance in inches from reference datum line to the CG

Question 4

Basic empty weight

Answer 4

GAMA

Standard plus equipment

Question 5

CG

Answer 5

Point aircraft would balance if suspended, mass center

In inches from datum line or percent of MAC

Question 6

CG limits

Answer 6

Forward and aft points within CG must be located

CG range

Question 7

Datum

Answer 7

Imaginary vertical plane or line from which all measurements of arm are taken
Established by manufacturer

Question 8

Floor load limit

Answer 8

Max weight per sqr in/foot

Question 9

Fuel load

Answer 9

Expendable part of the fuel

Question 10

Ramp or taxi weight vs take off weight

Answer 10

Difference due to fuel burn during taxi

Question 11

Max zero fuel weight - GAMA

Answer 11

Exclusive usable fuel

Question 12

Moment

Answer 12

Weight of an item x arm

In pound-inches

Question 13

Moment index

Answer 13

Divided by constant such as 100, 1000

Simplify weight and balance computation

Question 14

Payload - GAMA

Answer 14

Weight of occupants, cargo, baggage

Question 15

Standard empty weight - GAMA

Answer 15

Airframe, engines, fixed equipment, ballast, hydraulic fluid, unusable fuel, engine oil

Question 16

Standard weights

Answer 16

Use if actual weights are not available

Question 17

Station

Answer 17

Location in aircraft, distance in inches from datum

Question 18

Useful load

Answer 18

Pilot, co-pilot, passengers, baggage, usable fuel, drainable oil

Question 19

Determine load weight and CG

Computational method

Answer 19

List weight of aircraft, occupants, fuel (6lbs/gal), baggage
Weight x arm = Moment
Total weight and total moment
Total moment / total weight = CG

Question 20

Loaded weight and CG

Graph method

Answer 20

Graphs calculate moment

Find weight and draw line straight across until it intercepts with item, straight line down to read moment

Question 21

Other load weight and CG calculations

Answer 21

Table
With negative arm
With zero fuel,weight

Question 22

Calculate weight shift and CG
100lbs shifted from station 30 to 150
Moment increases total by 12000in-lbs

Answer 22

Moment at 150 = 100lb x 150in = 15000in-lb
Moment at 30 = 100lb x 30in = 12000in-lb
Moment change 15000-3000= 12000
Total moments = 616000 + 12000 = 628000
CG = 628000in-lb/8000lb (total weight) = 78.5in

Question 23

Calculate shift of CG

Answer 23

Weight shifted / total weight = ^CG / distance of weight shift
100 / 8000 = ^CG / 120
^CG = 1.5in
Previous CG + ^CG = new CG

Question 24

Add/Subtract ^CG

Answer 24

Shifting aft, add

Shifting forward, subtract