Abstract :
Maintenance cost consume at least 16% portion of airline operating costs
according to ICF SH&E, and 40 percent of the maintenance cost are used to
maintain the engine. High engine maintenance cost makes operators look for ways
to reduce that cost. One effective way according to CFM is to perform thrust derate
on takeoff phase. On this final assignment, author will analyze the EGT margin rate
of deterioration, effect of thrust derate on engine life and fuel consumption on
CFM56-7B engine.
Data sources used in this final assignment are from ECMS and processed
using Microsoft Excel software. The analysis is done by calculating the engine flight
cycle saving and fuel saving when the engine uses thrust derate in takeoff phase.
Several methods used for analysis are linear regression, second order and third
order polynomial regression, extrapolation, and quantitative correlation.
Analysis result shows the EGT margin rate of deterioration of CFM56-7B
engine with 24200 lbf thrust rating are 0.0221 to 0.0373 ?/cycle. Thrust derate
application can extend engine life up to 5015 EFC when 25 percent thrust derate
applied on takeoff phase. Engine flight cycle extension function is known y =
5.6052x2
+ 57.521x + 73.592. Thrust derate application can also reduce fuel
consumtion up to 173 kilograms when 25 percent thrust derate applied on takeoff
phase. The fuel saving fuction is known y = 0.0349x2
+ 5.8254x + 5.5819.