In concluding this section we review a couple of items that may be erroneously associated with fuel efficiency.
3.2.4.13. CENTER OF GRAVITY
All commercial aircraft must have their center of gravity (CG) forward of their center of lift in order to remain stable in flight. Fuel and payload disposition determines the CG position and the allowable range of CG positions is defined in the Flight Manual. On many aircraft a GG position towards the rear of the allowable range will allow a more aerodynamic configuration. However, for aircraft of the A320 Family CG position has a negligible effect on fuel consumption.
3.2.4.14. TAKE-OFF THRUST REDUCTION
A reduction in engine thrust during the take-off phase will reduce fuel flow. Reduced thrust implies reduced performance and will mean that the aircraft takes longer to achieve its optimum climb and cruise configurations. As a result, the use of reduced thrust using either de-rate or the flex (flexible) take-off technique will often increase overall fuel consumption. However, even in today’s environment of elevated fuel prices, this is more than compensated for by the reduction in engine stress and wear and consequent reduction in maintenance cost that thrust reduction offers.
Annual Saving (US$)

AIRCRAFT PROCEDURE FUEL 
CONSERVATION ACTION OVERVIEW

The following actions for operational cost reduction have been described in the preceding sections:
.
Use of fuel tankering,

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Minimizing use of APU,

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Adherence to minimum engine warm-up and cool-down periods,

.
Single engine taxi,

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Use of reduced take-off thrust reduction,

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Use of high engine power settings at low speed,

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Minimizing bleed air use,

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Departure route assessment,

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Take-off flap setting,

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Take-off acceleration altitude reduction,

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Approach procedure review,

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Landing flap configuration,

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Use of reduced thrust reverse.

3.2.5. MAINTENANCE INITIATIVES
3.2.5.1. IMPLICATIONS OF DISPATCHING UNDER MEL AND CDL
Operators are provided with a Master Minimum Equipment List (MMEL) that is the basis for their MEL (Minimum Equipment List). The MEL is a valuable tool for optimizing dispatch reliability because it defines the conditions under which the aircraft may be dispatched with specified equipment inoperative.  The conditions include the period during which the
Points of contact: aircraft can be operated with the MMEL content: fltops.mmel@airbus.com
CDL (FM) content: helene.doux@airbus.com
system inoperative and, in some
Aircraft performance: fltops.perfo@airbus.com
cases, requirements for additional fuel load.
　
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