1999 Weight and Balance Calculations

Source: 1999 Beartracks, Bob Barrows

*Hold this dimension for all engine installations unless weight and balance calculation problems are encountered

Bearhawk N33RB

Aft Sample Weight Arm Moment Forward Sample Weight Arm Moment
*Main Gear R 600 -1.63 -978 *Main Gear R 600 -1.63 -978
*Main Gear L 596 -1.63 -970 *Main Gear L 596 -1.63 -970
*Tail Wheel 75 199 14925 *Tail Wheel 75 199 14925
Front Seats 400 14 5600 Front Seats 200 14 2800
Cargo Area 530 57 30210 Cargo Area 0 57 0
Fuel lbs. 300 24 7200 Fuel lbs. 30 24 54
Totals 2500   55987 Totals 1500   15829
Gross Weight 2500     Gross Weight 2500    
C.G. Range 10.5″ – 22.5″     C.G. Range 10.5″ – 22.5″    
C.G. Range 16% – 34%     C.G. Range 16% – 34%    
C.G. Aft 22.4″     C.G. Forward 10.5″    
C.G. (MAC) 34%     C.G. (MAC) 16%    
Empty Weight – 1270* Empty Weight C.G. – 10.2″*

*As per weigh in of Proto II N33RB on 9-9-99

Note: Empty weight includes: 10 quarts oil, O-540 Lycoming Engine, no electrical system, no rear seats, utility door system and constant speed propeller (3-blade composite).

Forward C.G. = 15829/1501 = 10.5″     10.5/66 chord = 16%

Rear C.G. = 55987/2500 = 22.4″     22.4/66 chord = 34%

Do your first test flight with the c.g. between 13.5″ and 18.5″.

N6890R Weight and Balance

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