AIRPLANE
OPERATIONS
MANUAL
WEIGHT AND BALANCE
145 140 135 LB
JUNE 29, 2001
1-06-30
Page
1
Code
02
INDEX SYSTEM
When determining the aircraft center of gravity position it is necessary
to make calculations adding and/or subtracting the moment caused by
each individual item loaded in the aircraft.
Moment, per definition, is weight multiplied by the distance to a
reference point. If the moment of the aircraft and of the items loaded
on it are computed in reference to the aircraft datum, very long
numeric expressions would result.
As the operational usage of long numeric expressions may result in
safety problems (since personnel may get confused with the long
numbers), airlines usually adopt an
Index System
for weight and
balance purposes.
The Index System is just a convention for presenting aircraft or body
moments on a different measuring system. When using the Index
System, short numeric expressions result.
The Index System formula is presented below:
(
)
C
B
A
Arm
W
I
+
−
×
=
where:
I = Index
W = Aircraft or body weight
Arm = Aircraft or body center of gravity
A = Reference arm. Selected arm around which all index values are
calculated. On the balance chart CG envelope, the Reference
Arm CG% line is the only vertical CG% line. (*)
B = Constant used as a denominator to convert moment values into
index values. On the balance chart CG envelope, B controls the
CG% lines splay (splay decreases with increasing B). (*)
C = Constant used as a plus value to avoid negative index figures. It is
only used when computing the aircraft Operating Empty Weight
Index (OEI), and is not used when computing individual bodies
index influence. On the balance chart CG envelope, the
Reference Arm CG% vertical line is at C index units. (*)
(*) - Values for A, B and C may be chosen at the operator discretion.
Summary of Contents for EMB145
Page 3: ......
Page 610: ...EMERGENCY PROFILES AIRPLANE OPERATIONS MANUAL 1 03 95 Page 2 Code 03 SEPTEMBER 29 2000...
Page 611: ...AIRPLANE OPERATIONS MANUAL EMERGENCY PROFILES SEPTEMBER 29 2000 1 03 95 Page 3 Code 03...
Page 614: ...ABNORMAL PROFILES AIRPLANE OPERATIONS MANUAL 1 03 97 Page 2 Code 01 REVISION 25...
Page 615: ...AIRPLANE OPERATIONS MANUAL ABNORMAL PROFILES DECEMBER 20 2002 1 03 97 Page 3 Code 01...
Page 616: ...ABNORMAL PROFILES AIRPLANE OPERATIONS MANUAL 1 03 97 Page 4 Code 01 DECEMBER 20 2002...
Page 622: ...PERFORMANCE AIRPLANE OPERATIONS MANUAL 1 04 03 Page 4 Code 01 REVISION 34 INTENTIONALLY BLANK...
Page 1000: ...LOADING AIRPLANE OPERATIONS MANUAL 1 07 10 Page 4 Code 40 JUNE 28 2002 EMB 145 DOOR CLEARANCES...
Page 1070: ...AIRPLANE OPERATIONS MANUAL LOADING DECEMBER 20 2002 1 07 80 Page 3 Code 01...
Page 1072: ...AIRPLANE OPERATIONS MANUAL LOADING DECEMBER 20 2002 1 07 80 Page 5 Code 01...
Page 1074: ...AIRPLANE OPERATIONS MANUAL LOADING DECEMBER 20 2002 1 07 80 Page 7 Code 01...
Page 1367: ......
Page 1718: ...AIRPLANE OPERATIONS MANUAL ELECTRICAL MARCH 28 2002 2 05 10 Page 3 Code 01 CONFIGURATION 1...
Page 1720: ...AIRPLANE OPERATIONS MANUAL ELECTRICAL REVISION 22 2 05 10 Page 5 Code 01 CONFIGURATION 2...
Page 1724: ...AIRPLANE OPERATIONS MANUAL ELECTRICAL REVISION 23 2 05 10 Page 6C Code 01 CONFIGURATION 3A...
Page 1726: ...AIRPLANE OPERATIONS MANUAL ELECTRICAL REVISION 26 2 05 10 Page 7 Code 01 CONFIGURATION 3B...
Page 1766: ...AIRPLANE OPERATIONS MANUAL LIGHTING JANUARY 21 2002 2 06 05 Page 3 Code 01 COCKPIT LIGHTING...
Page 1768: ...AIRPLANE OPERATIONS MANUAL LIGHTING JANUARY 21 2002 2 06 05 Page 5 Code 01 GLARESHIELD PANEL...
Page 1770: ...AIRPLANE OPERATIONS MANUAL LIGHTING JANUARY 21 2002 2 06 05 Page 7 Code 01 OVERHEAD PANEL...
Page 1786: ...AIRPLANE OPERATIONS MANUAL LIGHTING JANUARY 21 2002 2 06 15 Page 7 Code 01 OVERHEAD PANEL...
Page 1792: ...AIRPLANE OPERATIONS MANUAL LIGHTING JANUARY 21 2002 2 06 20 Page 5 Code 01 OVERHEAD PANEL...
Page 1827: ...FUEL AIRPLANE OPERATIONS MANUAL 2 08 00 Page 2 Code 01 REVISION 17 INTENTIONALLY BLANK...
Page 1940: ...AIRPLANE OPERATIONS MANUAL POWERPLANT JUNE 28 2002 2 10 70 Page 5 Code 01 THRUST REVERSER...
Page 2030: ...AIRPLANE OPERATIONS MANUAL FLIGHT CONTROLS REVISION 19 2 13 20 Page 3 Code 01 RUDDER SCHEMATIC...
Page 2052: ...AIRPLANE OPERATIONS MANUAL FLIGHT CONTROLS REVISION 18 2 13 30 Page 3 Code 01 FLAP SCHEMATIC...
Page 2060: ...AIRPLANE OPERATIONS MANUAL FLIGHT CONTROLS JUNE 29 2001 2 13 35 Page 5 Code 01 CONTROL STAND...
Page 2159: ...AIRPLANE OPERATIONS MANUAL OXYGEN OCTOBER 02 2001 2 16 10 Page 3 Code 01 MAIN OXYGEN CYLINDER...
Page 2160: ...OXYGEN AIRPLANE OPERATIONS MANUAL 2 16 10 Page 4 Code 01 OCTOBER 02 2001 OXYGEN SERVICE PANEL...
Page 2176: ...OXYGEN AIRPLANE OPERATIONS MANUAL 2 16 20 Page 2 Code 01 REVISION 20 INTENTIONALLY BLANK...