Page 218 - Technology Roadmap Transportation

TECHNOLOGY VISION 2035

maintenance indications and therefore 3.1.2 Propulsion Systems
maintain the most optimum in-flight profile The propulsion system is the most important
besides weight reduction. Use of advanced part of an aircraft which provides the required
automated flight control technologies thrust for an aircraft to fly at desired speeds.
provide a greater leeway to the aircraft The aircraft propulsion system or the engines
designers without any compromise on is also critical as it happens to be the main
safety in view of better performance range source of both noise and CO emissions which
2
of such systems when compared to human have become the most critical element for
controlled mechanical flight control systems. sustainability of air transport in future.
Use of compact electromechanical actuators
for managing secondary control surfaces has Aircraft engines technology has made significant
further lead to reduction in weight. improvement in terms of fuel efficiency and
noise emission which is reflected in the fact
e) Passenger Cabin Interiors; Use of lighter that despite a 53% increase in traffic along
material sidewalls, panels, seats, etc. can offer with 41% increase in capacity, jet fuel demand
significant weight reduction and thereby a has increased by just 3% since 2000[9]. Fig 3.2
potential to reduce fuel consumption. Use shows the engine fuel consumption trend.
of light weight composites, improved design, Aircraft propulsion system using propellers
and use of plastic fasteners are some of the and fans have better aerodynamic efficiency.
technologies in this area which have led to However, they are not suitable for high speed
reduction in aircraft weight. subsonic/supersonic aircraft, as propellers suffer
aerodynamic losses due to shock waves at such
f) Electrical Power Systems; Modern aircraft speeds. For low speed air transport and cargo
like B787 have virtually eliminated the movement, turboprop engines are used as the
pneumatic systems which are powered by propulsion system due to their superior fuel
the bleed air from engine; the only onboard efficiency, whereas for high speed transportation
system in B787 based on engine bleed is turbofans are used.
the engine inlet anti-ice systems. This leads
to better efficiency and reduced mechanical The performance and fuel efficiency of a
complexity of the onboard systems, thereby turbofan engine depends upon the by-pass
reduce the maintenance cost with better ratio (BPR), higher the bypass ratio, higher is
reliability. the efficiency. The current generation of engines

FIGURE 3.2 ENGINE FUEL CONSUMPTION TRENDS[13]

ENGINE FUEL CONSUMPTION
COMET 4 AIRCRAFT FUEL BURN PER SEAT
100
707-120
90
80 747-100 747-400
% OF BASE (COMET 4) 60 DC-8-63 777-200 777-300ER 787 48%
70

50
A380
40
30
20 777-200 777-300ER
10 A380 82%
0 787
1950 1960 1970 1980 1990 2000 2010

YEAR OF THE MODEL INTRODUCTION

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