Pipistrel 890 AT 912 LSA, Руководство по эксплуатации для пилотов и дополнение к учебнику по летной подготовке

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Sample c.g. calculation
Guidelines
“G” is the total mass of empty aircraft. All calculations can be performed starting with aircraft empty
weight and empty weight centre of gravity (CG). Pilot’s and fuel shift Centre of Gravity backwards.
Refer to table of lever arms for more information (“Determination of CG” - Pag 6-3)
Reference MAC is 900 mm, R = 40 mm!
WARNING!
It is the responsibility of the pilot to make sure the airplane is loaded properly.
Operation outside of the prescribed weight and balance limitations could result in an accident
and serious or fatal injury.
Basic CG formulas and calculation
Read thoroughly. Note also that the basic c.g. at 275 mm will be used purely as an example.
First, weigh the aircraft according to the procedure described in this chapter and write down values of
G1 (sum of scale readings at main wheels) and G2 (scale reading at tail/front wheel). Then calculate the
position of c.g. in millimeters (mm) from the datum (wing’s leading edge at wing root).
Use the following formula:
( )
( ) ( )
-
275
-
-
306
-
where:
a is the distance from nose wheel axis to wing’s leading edge,
b
is the distance from main wheel axis to wing’s leading edge,
Second, determine the c.g. position in percentage (%) of Mean Aerodynamic Chord (MAC) with fol-
lowing the formula:
( )
( ) ( )
-
275
-
-
306
-
where:
CGmm
is the position of CG in millimeters (mm),
R
is the difference between wing’s leading edge and MAC’s leading edge (40 mm),
MAC is the Mean Aerodynamic Chord (900 mm).
Fuel and CG
The fuel shifts the CG backward, however the aircraft is factory tuned so that a full load of fuel and lug-
gage the CG stays forward of the aft allowable limit. Similarly, when the fuel tank is empty and there
is no baggage in the baggage area, the CG is backwards of the forward allowable limit. In every case,
the fuel does not shift the CG out of limits.
Weight and balance
6-4