Weight & Balance

Question 1

Define the following

Answer 1

Empty Weight: airframe, engines, parmanently installed equipment, unusable fuel, maybe undrainable oil.

Gross weight: max allowablw weight of the airplane and its contents

Useful load: pilot, copilot, pax, baggage, usable fuel, drainable oil

arm: horiztonal distance in inchers from the reference datum line to the center of gravity of the item

Moment - product of the weight multiplied by its arm (expressed in pound iches)

Center of Gravity - the point about which an aircraft would balance; expressed in inches from datum

datum: an imaginary vertical plan or line from which all measurements of arm are taken.

Question 2

Basic W&B calculations to find CG

Answer 2

Wieght x Arm = moment

Total moment / total weight = CG

Question 3

Overloaded airplane characteristics

Answer 3

higher takeoff speed
longer takeoff run
reduced rate and angle of climb
lower max altitude
shorter range
reduced cruising speed
reduced maneuverablitiy 
higher stalling speed
higher landing speed
longer landing roll
excessive weight on nosewheel

Question 4

Forwrd CG characteristics

Answer 4

higher stalling speed (increased wing loading)
slower cruising speed (increased drag, greater AoA required to maintain altitude)
more stable
greater back elevator required (longer TO roll, higher approach speed, problems with landing flare)

Question 5

Aft CG characteristics

Answer 5

Lower stall speed (less wing loading)

Higher cruise speed (reduced drag, smaller AoA)

Less stable (stall and spin recovery more difficult)

Question 6

Weights for these things?

Answer 6

gas - 6lbs/gal
oil - 7.5lbs/gal
water - 8.35lbs/gal