This paper discourses the descent trajectory in the Melbourne East West Corridor, in the aspect of fuel efficiency for carbon savings. Three top of descent approaches put down the foundation for the research: The Reduced Vertical Separation Minimum, Free Route Experimental Encounter Resolution, and the Continuous Descent Approach that is practiced within the Melbourne airspace. Using a theoretical construct of fuel fraction during loiter, outline of approach and landing the derivative of fuel burn and correlated emissions can be defined. A single aircraft type of the Australian flag bearer, Quantas Airways Limited is to be selected, in a sample size to be determined on the volume of available information. On the overall, this research is typical a case study in a framework of comparative analysis using a single equation. At the given congestion of Melbourne Airport year-on-year 200,000 aircraft movements for 29 million passengers; the outcome of this research is expected to show positive results in fuel efficiency for carbon savings. Ease of approach and reduced time to land are thought to be the substantive variables due the Melbourne East West Corridor.

1. Descent Trajectory✈
The Melbourne East West Corridor

2. Optimal flight descent ✈ | 2
Abstract
This paper discourses the descent trajectory in the Melbourne East West Corridor, in the aspect
of fuel efficiency for carbon savings. Three top of descent approaches put down the foundation
for the research: The Reduced Vertical Separation Minimum, Free Route Experimental
Encounter Resolution, and the Continuous Descent Approach that is practiced within the
Melbourne airspace.
Using a theoretical construct of fuel fraction during loiter, outline of approach and landing the
derivative of fuel burn and correlated emissions can be defined. A single aircraft type of the
Australian flag bearer, Quantas Airways Limited is to be selected, in a sample size to be
determined on the volume of available information.
On the overall, this research is typical a case study in a framework of comparative analysis using
a single equation.
At the given congestion of Melbourne Airport year-on-year 200,000 aircraft movements for 29
million passengers; the outcome of this research is expected to show positive results in fuel
efficiency for carbon savings. Ease of approach and reduced time to land are thought to be the
substantive variables due the Melbourne East West Corridor.

3. Optimal flight descent ✈ | 3
Introduction
The Melbourne Airport has preconditioned flight paths defined by the seasons of winds that
dominant in summer in a south to south west direction and a north to northwest direction over
the winter. A green wedge corridor seats to the north and west, well away the urban region
(Melbourne Airiport, 2019). Flight paths depart to the north to northwest and approach the
terminal from the east and southeast, overhead the suburban region, with alignment notices at
least ten kilometres out and observing a glide slope of three degrees.
To ease congestion over the peak hours LT/O delays, Melbourne Airport is to take up landing
approaches from west on the east-west Runway 09, and lift off to the south off Runway 16.
Crafted as closely as possible to the original, these flight paths are to operate in tandem the rest.
Figure 1 Arrival path corridors for Runway 09 (Air Services 2019)

4. Optimal flight descent ✈ | 4
Research Statement
This research discourses The Melbourne East West Corridor in the aspect of descent trajectory
for boosting fuel efficiency for carbon savings, posturing safety to be succeeded by flight
performance improvement.
Flight descent is executed in a combination of speed and altitude, where the aircraft manoeuvre
enables a stable approach from an altitude above ground 3000 feet for the ILS Melbourne
Airport: To be able to land safe. Landing an aircraft depletes an immense amount of fuel
consequential its respective descent trajectory and existing environment conditions (NATS
2009). Taking aside any other variable such as fatigue and pilot fault, or ATCO interaction and
terminal procedure; a top of descent manoeuvre relative to wind forecast accuracy, marks down
the direct impact on fuel burn and carbon savings (Bronsvoort et al 2011).
To be clear, the descent trajectory to be studied begins from the top of descent, loiter, and
landing. As such, fuel efficiency connotes a fraction of the fuel consumption in flight.
Research analysis confines to a single type of aircraft of the Australian flag bearer, Quantas;
using a sample size of flights relative to the data made available.
The Research question
Does The Melbourne East West Corridor infer an optimal flight path for fuel efficiency and
carbon savings?
Literature Review
Attitudes to incur fuel efficiency and carbon savings begin with a stable approach, otherwise the
descent trajectory. An approach subscribes to varying techniques practiced within the specific
airspace as applicable. Those that boost fuel efficiency for carbon savings are: Reduced Vertical
Separation Minimum, Free Route Experimental Encounter Resolution, and the Continuous
Descent Approach.

5. Optimal flight descent ✈ | 5
Reduced Vertical Separation Minimum
The concept of Reduced Vertical Separation Minimum, otherwise RVSM was initially employed
in the North Atlantic in 1997, and later on practiced across Europe. The RVSM technique using a
minimum separation of 1000 feet, permits the aircraft on a flight path of preferred altitude to
raise airspace utilisation efficiency as prescribed by ICAO, because it enables tighter approaches
thus reduces distance flown (Hansman, 2010).
On an RVSM flight, descent trajectory can begin at 10,000 feet with sink rate of 900 miles per
minute. For congested airspaces adjacent terminals, the synchronisation of arrivals regulates
airspeed at altitudes. ATCO contributes to stable flight approaches and descents by prescribed
exchanges of distance and speed. Of course safety which is only succeeded by flight
performance improvements considers situations such as a slower aircraft following behind by
faster moving flight vehicle that entails lateral otherwise vertical diversion and corresponding
fuel burn absorption (Cao, 2011). The North Pacific region finds a beneficial return of RVSM of
about one percent in terms of fuel optimisation with a saving valued at USD8 million, while
Europe finds a USD60 million savings per annum. Its correlated carbon savings is about 1.6
percent in CO2 emissions, one percent less on NOx emissions and 260 tons less in sulphur oxide
per annum (International Civil Aviation Organization, 2019).
Continuous Descent Approach
The Continuous Descent Approach technique provides arrivals the freedom to pan out a
preferred continuous descent trajectory. The practice encourages the reduction of fuel burn and
noise; carbon emissions and flight duration. A CDA vertical profile requires more vectoring
space and a large portion of the airspace is restricted to other descending flights. As a result,
landing intervals take up 3.2 minutes from the average of 1.8 minutes (European Organisation
for the Safety of Air Navigation, 2011). Resolving CDA conflicts in highly congested terminals
use a combination of trajectory and holding techniques. This developed the FACET which
applies CDA profiles by assigning TOD on arrivals, specific to aircraft type. On the average, the
glide slope uses a three degree descent for low levels of fuel burn throughout its trajectory (Civil
Aviation Authority, 2016).

6. Optimal flight descent ✈ | 6
FuelBurnandSpeedBrake(kgs/min)
10000
20000
30000
Flightaltitude(feet)
Top of descent
Level off
•Holding or level off
•CDA
•CDA fuel burn rate
•Holding fuel burn rate
Distance from runway to threshold (NM)
100
80
60
40
20
0
20 40 60 80 100
Figure 2 Continuous Descent Approach showing fuel burn (Cao 2011)
Free Route Experimental Encounter Resolution
The concept of autonomous aircraft operations perceives free-flight airspace. FREER is an
experimental solution for converging aircrafts by practicing precedent flight rules in the physical
airspace structure. For this technique, airspace vertical separation is managed to specific arrival
descent profiles, from a suitable higher altitude (European Organisation for the Safety of Air
Navigation, 2011).
FREER postulates to devolve certain functions to the flight crew, otherwise an Autonomous
Aircraft Operations or AAO using automation. FREER supports fuel optimisation and increases
airspace capacity; which encourages concentrated freedom of movement and flexibility for flight
operations. With this innovation, the airspace user reduces operating cost at the same time
ensures safety but is explorative in form (Civil Aviation Authority, 2016).

7. Optimal flight descent ✈ | 7
Fuel burn implications on carbon emission
A Pilot in Command has full responsibility to proceed with a stabilised approach and optimal
descent. Nearly 85 percent of the potential fuel reduction result from optimised descent
trajectories at altitudes above MSL and below 20 000 feet. A single level off consumes about 15
percent of flight fuel burn and reduces the impact on environment without sacrificing safety.
This is achievable through the invention of practices other than ground-to-air services across the
flight traffic region. Reversely, touch down delay waste about 20.96 percent of the potential fuel
savings. On the aspect of aviation gas fuel burn emissions the table below summarises these
factors (Gwiggner, 2010).
Table 1: Default fuel use and emissions factors for LTO cycle in kg/LTO
(IPCC Guidelines on National Greenhouse Gas Inventories)
Aircraft type CO2 CH4 N2O NOx CO NMVOCs SO2 Fuel
A300 5470 1.0 0.2 27.21 34.4 9.3 1.7 1730
A310 4900 0.4 0.2 22.7 19.6 3.4 1.5 1550
A320 2560 0.04 0.1 11.0 5.3 0.4 0.8 810
BAC1-11 2150 6.8 0.1 4.9 67.8 61.6 0.7 680
BAe 146 1800 0.16 0.1 4.2 11.2 1.2 0.6 570
B707* 5880 9.8 0.2 10.8 92.4 87.8 1.9 1860
B727 4455 0.3 0.1 12.6 9.1 3.0 1.4 1410
B727* 3980 0.7 0.1 9.2 24.5 6.3 1.3 1260
B737-300 2905 0.2 0.1 8.0 6.2 2.0 0.9 920
B737* 2750 0.5 0.1 6.7 16.0 4.0 0.9 870
B737-400 2625 0.08 0.1 8.2 12.2 0.6 0.8 830
B747-200 10680 3.6 0.3 53.2 91.0 32.0 3.4 3380
B747* 10145 4.8 0.3 49.2 115 43.6 3.2 3210
B747-400 10710 1.2 0.3 56.5 45.0 10.8 3.4 3390
B757 4110 0.1 0.1 21.6 10.6 0.8 1.3 1300
B767 5405 0.4 0.2 26.7 20.3 3.2 1.7 1710
Caravelle* 2655 0.5 0.1 3.2 16.3 4.1 0.8 840
DC8 5890 5.8 0.2 14.8 65.2 52.2 1.9 1860
DC9 2780 0.8 0.1 7.2 7.3 7.4 0.9 880
DC10 7460 2.1 0.2 41.0 59.3 19.2 2.4 2360
F28 2115 5.5 0.1 5.3 54.8 49.3 0.7 670
F100 2340 0.2 0.1 5.7 13.0 1.2 0.7 740
L1011* 8025 7.3 0.3 29.7 112 65.4 2.5 2540
SAAB 340 945 1.4(E) 0.03(E) 0.3(E) 22.1(E) 12.7(E) 0.3(E) 300 (E)
Tupolev154 6920 8.3 0.2 14.0 116.81 75.9 2.2 2190
Concorde 20290 10.7 0.6 35.2 385 96 6.4 6420
GAjet 2150 0.1 0.1 5.6 8.5 1.2 0.7 680

8. Optimal flight descent ✈ | 8
The emission factors for aviation have been derived from an average of a number of typical
aircraft. For domestic aircraft, the average fleet is represented by Airbus A320, Boeing 727,
Boeing 737-400, Mc Donell Douglas DC9 and MD 80 aircraft. The old fleet is represented by
Boeing B737 and Mc Donell Douglas DC9. For international traffic the average fleet is
represented by Airbus A300, Boeing 767, B747 and Mc Donell Douglas DC10, whilst the old
fleet is represented by the Boeing B707, Boeing 747 and Mc Donell Douglas DC8. Sulphur
content of the fuel is assumed to be 0.05% S for both LTO and cruise activities.
Total CO2 emissions
( ) ( ) ( )
Total CO2 emissions
( )( )
( ) ( )
Where
W payload = Payload mass
Payload mass = (Passenger traffic or demand) (Average load factor) (Fleet mix aircraft size)
Average load factor = Available seats/ Passengers
Fleet mix aircraft size = nf flights / available seats
W empty = empty mass
R/V = Range and speed
SFC = Special fuel consumption (propulsion)
D/L = Drag/Lift ratio

9. Optimal flight descent ✈ | 9
Proposed Methodology
The methodology has a shell of a case study, by comparative analysis of fuel efficiency for
carbon savings between two scenarios: With and without The Melbourne East West Corridor.
Data is to be gathered from the Melbourne Airport authorities and Qantas Airways Limited.
Figure 3 Research Structure
The case study methodology evaluates a specific case and is non-generic in form. The theoretical
construct is used to surface details and insights from the aviation community in the specific
terminal (European Commission, 2013).
For purpose of fuel consumption during landing, the proposed equation borrows the equation of
Professor Tulapurkara on computation of fuel consumption for a fraction of the flight
(Tulapurkara, 2019)
dWf = TSFC x T x dt
Where
T = W (Coefficient of drag/Coefficient of lift)
TSFC is the specific fuel consumption in N/N-hr
dt is the time interval from top of descent in hours: deriving distance covered in kilometres
and where V is the equivalent flight speed in m/s
1
Analysis & synthesis
Define & Describe
Learn & Use
Investigate
LITERATURE REVIEW
/SYNTHESIS AND ANYSIS OF DATA
CASE METHOD
/ CBO RESULTS
CONCLUSION
2
3
4
Give recommendations on how the
technique can improve on fuel efficiency
and descend trajectory
Investigate the present
trajectory in use by the
Melbourne East West
Corridor
Evaluate the quantity fuel burn
saved in relation to descend
trajectory.
Outline potential areas of
conflict or inaccuracy

10. Optimal flight descent ✈ | 10
Expected Research Outcomes
The expected outcome is that there is good fuel efficiency and carbon savings using the
Melbourne East West Corridor, when compared to that as of the previous. First off is that landing
in Melbourne Airport is typically delayed, which by itself is fuel consumption. Second is that the
decongestion eases on the flight path descent trajectory with more pilot command over the
combination of airspeed and altitude; effectually consuming more fuel.

11. Optimal flight descent ✈ | 11
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