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The Estimation of the Engine Emission
The Scholar Journal for Sciences & Technology VOl. 1 -NO. 2 -29/07/2023
http://www.sst.journalnea.com
3
ISSN (Print) 2794-7629 Received 13/04/2023
ISSN (Online) 2794- 4549 Accepted 10/06/2023
FULL PAPER
uel F etJnsuing from Emissions Engine EThe Estimation of the
Combustion and its Contribution to World Wide Warming at Aden
tudySInternational Airport. Case
Prepared by
Rokhsana Mohammed Ismail
Director-Science &
Technology Center
University of Aden
ywastd@gmail.com
Abstract
This paper is an try and have a look at the quantity of plane
emissions due to the combustion of jet fuel for the duration of the
touchdown and takeoff (LTO) operations at Aden International
Airport (AIA) in 2018. All statistics changed into taken from the
airport's statistic data. The have a look at centered on the
subsequent emitted plane gases: (CO2,CH4, N2O, CO, NMVOCs
and SO2). It was found that there were 3,148 LTO activities in the
course of 2018 which resulted in an approximate amount of
4,747,940 kg CO2, 346.68 kg CH4, 166.2 kg N2O, 23482 kg CO,
3186.9 kg NMVOCs and 1495 kg SO2. Boeing 737, Airbus 310
and CRJ700 were found to be the most polluting aircraft, while
other aircraft were less polluting. Furthermore, despite the fact
that there was very little aircraft traffic in Aden International
Airport compared with either Sana'a or any of the remaining
airports who had always been a major aviation hub, however, it is
possible to use these results as a useful scientific base for the
assessment of aircraft emissions locally, regionally or
internationally. Finally, a number of recommendations have been
presented by the study aimed at enhancing and developing the
environment in the vicinity of the airport.
Key words: Aden International Airport, aircraft emissions,
The Estimation of the Engine Emission
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1. Introduction
Human beings, like different dwelling organisms, have usually inspired their
18th -environment. It is handiest seeing that the start of the Industrial Revolution, mid
ar large scale, century, that the effect of human sports has started to increase to a f
continental or maybe global. Human sports, mainly the ones concerning the intake of
fossil fuels for commercial or home usage, and biomass burning, produce greenhouse
ntific proof gases that have an effect on the composition of the surroundings[1]. Scie
shows that human sports consisting of burning fossil fuels and deforestation have
side the surroundings appreciably extended the percentage of greenhouse gases within
during the last a hundred and fifty years [2].
Research on climate change has recognized a big range of sources that cause the
greenhouse effect. The biggest sources of those emissions, especially in developed
economies, are electric powered utilities and the transportation sector (fig.1) [3].
Aviation is one of the transportation sorts producing emissions which have the capacity
to effect air pleasant within side the local, local and international environments[4].
ICAO/CAEP’s preliminary estimate is that the full extent of aviation CO2 emissions in
2006 ( both domestic and international ) is within side the variety of six hundred million
tones. At present, aviation accounts for approximately 2% of general international CO2
emissions (fig.1) and approximately 12% of the CO2 emissions of all transportation
sources [5,6]. While the impact of noise on communities around airports has historically
been the most prominent environmental issue of aviation, the local and global effects of
aircraft emissions on air quality are emerging as issues of equal, if not greater,
importance [7].
Figure 1: Aviation emissions and their contribution to global environment [6]
In the scientific literature there are many scientists and organizations carried out
numerous studies considering estimation of the aircraft emissions at airports around a
world. For example, EPA [8], Perl et al. [9] and Stefanou and Haralambopoulos [10]
have studied and calculated annual environmental loads and proved that significant
amounts of pollutants are received in areas around airports.
There are a lot of air pollution present as gaseous and particulate emissions from
aviation and aviation- related activities which could probably effect human health and
the environment. They are: NOx Nitrogen oxides along with (N2O); VOC Volatile
natural compounds (along with non-methane unstable natural compounds (NMVOCs);
The Estimation of the Engine Emission
The Scholar Journal for Sciences & Technology VOl. 1 -NO. 2 -29/07/2023
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5
Carbon dioxide (CO2); CO Carbon monoxide; SOx Sulphur oxides; and PM
Particulate matter (fraction size PM 10 and PM10) [4].
The ability damaging consequences of air pollution released within an aircraft’s
landing and takeoff cycle (LTO) and airport-related sources of emissions can make
contributions to the degradation of air quality in their close by communities. The table
(1). indicates the representative health effects of a few emissions released from
aircrafts.
Table 1. Potential effects on human health due to various species of emissions [11]
Pollutant
Health effect
CO – Carbon Monoxide
● Cardiovascular effects, especially
in those persons with heart conditions
HC – Unburned Hydrocarbons
( a primary component of Volatile
Organic Compounds, or VOC )
● Eye and respiratory tract infection
● Headaches
● Dizziness
● Visual disorders
● Memory impairment
NOx – Nitrogen Oxides
● Lung irritation
● Lower resistance to respiratory infections
O3 – Ozone (HC is a precursor
for ground-level O3 formation )
● Lung function impairment
● Effects on exercise performance
● Increased airway responsiveness
● Increased susceptibility to respiratory infection
● Increased hospital admissions and emergency room visits
● Pulmonary inflammation, lung structure damage
PM – Particulate Matter
( smoke is a primary component
of PM.)
● Premature mortality
● Aggravation of respiratory and cardiovascular disease
● Changes in lung function
● Increased respiratory symptoms
● Changes to lung tissues and structure
● Altered respiratory defence mechanisms
During the past five years, in 2018 Aden International Airport had one of the
maximum number of landing and take-off (LTO) aircraft operations. 3907 LTO-cycles
were made [12]. Of course, this process left behind a lot of pollutants from aircraft
engines. So this research is an attempt to estimate the aircraft emission gases such as:
(CO2,CH4, N2O, CO, NMVOCs and SO2) at Aden International Airport to use them in
any local, regional or even international inventories and also to help local authorities to
improve environmental situation in the vicinity and surrounding areas by offering some
helpful recommendations.
2. Materials and methods
2.1. Study area
Aden International Airport is one of the most important airports in the Yemen
Republic. Aden International Airport is an international
airport in Aden, Yemen (IATA: ADE, ICAO: OYAA) and the oldest airport in the
Arabian peninsula. Prior to its use as a civil air facility, the aerodrome was known
as RAF Khormaksar, which opened in 1917 and closed as an RAF station in 1967. In
The Estimation of the Engine Emission
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the 1970s and 1980s it was both a civilian airport and a Soviet Air Force air base. It
continues to be used for military purposes by the Yemeni Air Force.
(2005-2025), has population of 1,218,000 people [13]. During the last four years there
were a noticeable increase in the aircraft movements and also in the number of arriving
and departing passengers in the Aden airport (fig. 3 and 4).
From the figure 3 it is clear that the number of the aircrafts that used AIA
increased from 1578 in 2015 to 3907 in 2018, i.e. more than twice. Despite this
high increase in the number of aircrafts operation, the number of the arriving and
departing passengers remained still very low comparing with aircraft movements.
This is because Yemenia airlines has reduced the domestic flights since October
2015
Fig.2. Aden airport by Google map
Fig.3. Annual distribution of aircraft Fig. 4. Numberof arriving and departing
passengers in Aden International
Airport movements at Aden International
Airport
The Estimation of the Engine Emission
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2.2. Flight operations:
Emissions from an plane originate from fuel burned in plane engines. The fuel
utilization and emissions rely on the fuel type, plane type, engine type, engine load and
flying altitude. Operations of an plane are typically divided into foremost parts [14].
1. The Landing/Take-off (LTO) cycle which includes all activities near the airport
that take place below the altitude of 3000 feet (1000 m). This therefore includes
taxi-in and out, take-off, climb-out, and approach-landing (fig.5).
2. Cruise which here is defined as all activities that take place at altitudes above
3000 feet (1000 m). No upper limit of altitude is given. Cruise, in the inventory
methodology, includes climb to cruise altitude, cruise, and descent from cruise
altitudes.
The focus of this study was to determine the aircraft emissions during aircraft
LTO cycles (domestic and international) in 2018 at AIA. This is because the most
emissions produced from aircrafts happen in this part of the flight.
Figure 5: A typical flying cycle which includes LTO-cycle
2.3. Calculating aircraft emissions:
The ICAO emission stock methodologies constitute three approaches: Simple,
Advanced and Sophisticate Approach [4]. The desire of any of those techniques
relies upon especially on records availability and, of course, their accuracy will
increase from the Simple to the Sophisticated Approach.
In this paper the Simple Approach turned into used, due to the fact for
estimating plane engine emissions it calls for most effective the quantity of plane
movements (over a certain period of time, together with a year) and the type of
every plane involved in each movement. To calculate the emissions was used the
equation [4]. For every plane type, the quantity of LTO cycles of that plane (over
the evaluation length) multiplies with the aid of using the emissions aspect for every
of the pollutant species posted in ICAO emissions stock after which upload up the
values for all of the plane to get the quantity of general emissions (in kilograms) for
every pollutant.
The Estimation of the Engine Emission
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Ex = (LTO cycles of y) X EFx
Where:
Ex- Emission of pollutant x, [kilograms], x- (CO2 - CH4- N2O- CO-
NMVOCs- SO2);
LTO- Number of the landing and take-off cycles of y, [LTO]
Y- The aircraft types that landed and departed at MIA
EFx-Emission factor of pollutant x, [kg/LTO]
For Aden International Airport there were 3907 LTO-cycles during 2018. But
only 3148 LTO of particular type of aircrafts were known (data were available). In
the rest 759 LTO-cycles operations the type of aircrafts was unknown. And also it's
very important to mention that some aircrafts had no information about their
emission factors, neither in ICAO data base nor in any other place. In this case it is
helpful to use supplementary information such as weight, number of engines, size
category, range, etc. to identify a suitable equivalent aircraft that has available data,
as recommended by ICAO in such cases.
3. Results and discussion:
3.1. LTO-cycles operations:
During the 2018 at Aden International Airport there had been 3907 LTO-cycles
operations. Of 3148 LTO-cycles become regarded every kind of plane that used the
airport (desk 2), however 759 LTO – had been unknown (there had been no to be
had data, perhaps they had been army airplanes). For this reason, the LTO emissions
of those aircrafts had been now no longer calculated into the overall account of
emissions.
Table 2: Shows the air traffic movements by the type at
Aden International Airport during 2018
Number of
LTO-cycles
Aircraft
type
Number of
LTO-cycles
Aircraft
type
Number of
LTO-cycles
Aircraft
type
1
EK 76592
15
AN-32
1180
CRJ 700
1
CL-601
14
C-55
765
PA-28/C170
1
A-33
11
IL-76
500
B 737-8
1
BH-44
10
AN-12
223
A310
1
C-235
9
DC-09
152
DH 8/9
1
C-160
7
ER 120
112
MD 82
1
BH-41
3
BE-20
53
B-733
1
JSS-41
2
GLF-4
36
IL-18
759
Unknown
2
BELL 421
28
AN-26
3907
Total
2
B-212
16
DC-93
The Estimation of the Engine Emission
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It is clear from the table 2 that CRJ-700, PA-28/C170, B 737 , A310 , DH 8/9 , MD
82 and B-733 were the most common aircrafts used the AIA in 2018. These aircrafts
comprised more than 76% of all LTO cycles at AIA in 2018. And it's also obvious that
only CRJ-700 (AL-SAEEDHA) aircrafts comprised about 30% of the all LTO cycles
operations at AIA (fig.6).
By comparison with Boeing or Airbus airplanes which are frequently used by
Yemenia airline, CRJ-700 (AL-SAEEDHA) is small by size and it began to function in
the end of 2008 [15]. This in turn explains the big jump in the traffic movements of
aircrafts at AIA between 2014 and 2015, from 1891 LTO in 2014 to 3891 LTO in 2015
(see fig.3), but the motion of passengers were small, from 143000 passengers in 2014 to
148000 passengers in 2015.
Figure 6: shows the most common aircrafts that
made more than 50 LTO at AIA in 2018
3.2. LTO-cycle calculated emissions:
The total estimation of calculated aircraft pollutants (CO2 - CH4- N2O- CO -
NMVOCs- SO2), emitted at Aden International Airport during 3148 LTO operations in
2018 were broken down into detailed analysis below.
CO2 emissions:
Although typically taken into consideration because the worst greenhouse gas, in fact
carbon dioxide isn't the handiest greenhouse gas. However, as it has the very best
attention within side the ecosystem as compared to all of the different greenhouse gases
that human emit (besides water vapor), it's far the only that has the most important
impact [16]. The overall emissions of the CO2 emitted from all aircrafts that used Aden
International Airport for the duration of 2018 have been approximately 4747940 kg.
The fig.-7A indicates the emissions from every sort of aircrafts.
The Estimation of the Engine Emission
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It was found that the most common aircraft types that emitted about 93% of CO2
emissions and which had more than 50 LTO operations at AIA in 2018 are CRJ-700,
PA-28/C170, B 737 , A310 , DH 8/9 , MD 82 and B-733. Although Boeing 737 aircraft
made less LTO operation (approximately 500) than CRJ-700 (about 1180 operations),
but the CO2 emissions per LTO cycle were the highest for Boeing 737 about 29% of all
CO2 emissions (fig.7B). It happens because the large jet engines use a lot of fuel
and of course emissions depend on the LTO emissions factors of each type of aircrafts.
Figure 7: A- shows the CO2 emissions from each aircraft, and B- the percentage of emissions
from aircrafts that have made more than 50 LTO at AIA in2018
CH4 emissions:
Due to its exceptionally quick lifestyles time within side the atmosphere (9-15 years)
and its worldwide warming potency — 20 instances greater powerful than carbon
dioxide in trapping warmness within side the atmosphere, methane is at the pinnacle of
greenhouse gases, as pronounced with the aid of using the Environmental Protection
Agency [16].
The estimation of CH4 emissions during all LTO operation of all aircrafts that used AIA
in 2018 were about 346.68 kg. The figure 8A shows CH4 emitted from each aircraft
type. It's clear that the A310 aircraft type made the highest CH4 emissions and that was
about 41% of all CH4 emissions at AIA (fig.8B).
N2O emissions:
N2O is a greenhouse fuel line with incredible international warming potential (GWP). It
has 298 instances greater impact 'in line with unit weight' (GWP ) than carbon dioxide.
The total calculated N2O emissions from all aircrafts were 166.2 kg and the figure 9A
shows the N2O emissions from each aircraft. Boeing 737, A310 and CRJ 700 emitted
more emissions than all other aircrafts about 30%, 27% and 21% respectively (fig. 9B).
The Estimation of the Engine Emission
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Figure 8: A- shows the CH4 emissions from each aircraft, and B- the percentage of emissions
from aircrafts that have made more than 50 LTO at AIA in2018
Figure 9: A- shows the N2O emissions from each aircraft, and B- the percentage of emissions
from aircrafts that have made more than 50 LTO at MIA
CO emissions:-
Carbon monoxide is the maximum not unusual place sort of deadly air poisoning in
lots of countries. It is highly toxic to humans and animals in higher concentrations. The
total emissions of the CO emitted from all aircrafts that used AIA in 2018 were 23482
kg. The figure 10A shows the emissions from each type of aircrafts.
The Estimation of the Engine Emission
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Figure 10: A- shows the CO emissions from each aircraft, and B- the percentage of emissions
from aircrafts that have made more than 50 LTO at AIA in2018
In this case, it's clear that CRJ 700 aircraft emitted more than any aircraft type used
by AIA, i.e. about 34% (fig.10B). Since the carbon monoxide is considered one of the
most dangerous pollutants, it can be said that this type of aircraft is the most harmful to
the environment and humans among all aircrafts.
NMVOC emissions:-
Non-methane unstable natural compounds are a big sort of chemically one-of-a-kind
compounds, like for example, benzene, ethanol, formaldehyde, etc. Essentially,
NMVOCs are same to VOCs, however with methane excluded. Many of NMVOCs are
poisonous to human beings and dangerous to the environment [17].
The total emissions of NMVOCs at AIA in 2018 were about 3186.91 kg. Each aircraft
type emitted less or more as shown in fig.11A. However Airbus 310 emitted more than
any other aircrafts, i.e. about 40% NMVOCs (fig.11B).
SO2 emissions:-
Sulfur dioxide is a poisonous gas that causes detrimental impacts on human health
and the environment. The major health concerns associated with exposure to high
concentrations of SO2 include breathing difficulties, respiratory illness, and aggravation
of existing cardiovascular disease. In addition to the health impacts, SO2 leads to acid
depositions in the environment [18].
The Estimation of the Engine Emission
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Figure 11: A- shows the NMVOCs emissions from each aircraft, and B- the percentage of
emissions from aircrafts that have made more than 50 LTO at AIA in2018
The total SO2 emissions in 2018 at AIA were 1495 kg. Figure 12A shows the
quantities of SO2 emitted from each kind of airplanes in 2018 at AIA. The most
emissions of SO2 were from B737 29%, CRI 700 26% and A310 22% respectively.
Figure 12: A- shows the SO2 emissions from each aircraft, and B- the percentage of
emissions from aircrafts that have made more than 50 LTO at AIA in2018
4. Conclusion and recommendations
From above-mentioned analysis, it is clear that the most damaging airplanes to the
environment are B 737, Airbus 310 and CRJ700 (table 3). In 2018 at AIA during 500
LTO-operations Boeing 737-and its modifications have emitted about 29% CO2, 30%
N2O and 29% SO2. So, from an environmental perspective, this plane is the biggest
polluter of the area.
Airbus 310 has been considered the second environmental polluter with two records
of 41% of CH4 and 40% of NMVOCs, and finally it's CRJ-700 with one greenhouse
record of 34% of CO.
The Estimation of the Engine Emission
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Table 3: The three most polluting aircrafts of AIA during LTO-operations in2018
In general, it’s found that 3148 LTO operations at Aden International Airport in
2018 have led to emissions of the following quantities of engine gases: 4747.940 ton of
CO2, 0.35 ton of CH4, 0.17 ton of N2O, 23.48 ton of CO, 3.19 ton of NMVOCs and
1.50 ton of SO2 (fig. 13).
Figure 13: The total calculated aircraft engine emissions of 3148 LTO operations
at Aden International Airport in 2018
If we take into account the aircrafts traffic at other airports such as in Sana'a or Al-
Mukalla, or even neighboring countries, these quantities of gases are very low. But it
must be noted that the effect on the surrounding areas of the airport with long term
might be greater. Especially, since there are many studies that indicate the impact of
airports on surrounding areas (on human health and on the environment). Therefore it is
necessary:-
To not allow the old aircraft to land and take off from the International
Aden Airport because they usually have large rates of emissions.
To Assess of the environmental situation of the airport zone and
neighboring areas through a field study to measure the concentrations of
pollutants.
To establish of short corridors (taxiway) from/to the runway and last
parking of the aircraft to minimize the amount of fuel used and thereby
Pollutants
The most polluting aircrafts at AIA
in 2018 for specific emissions
The position of aircraft in
terms of pollution
Aircraft
type
Percentage, of all
emissions
Aircraft type
Position
CO2
B737
29%
B737
1
CH4
A310
41%
N2O
B737
30%
A310
2
CO
CRJ-700
34%
NMVOCs
A310
40%
CRJ-700
3
SO2
B737
29%
The Estimation of the Engine Emission
The Scholar Journal for Sciences & Technology VOl. 1 -NO. 2 -29/07/2023
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15
reduce engine emissions.
5. Acknowledgments
The author is grateful for the support of the general director of the Aden
International Airport Mr. Abdel-Raqeeb Al-Amri, as well as want to thank all who
contributed to provide any specific information for this study.
6. References
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