The omnidirectional runway with infinite
heading as a futuristic runway concept for
future free route airspace operations
Emre Aydog an
Department of Air Traffic Control, Eskisehir Technical University, Eskis
ehir, Turkey, and
Soner Demirel
Department of Air Traffic Control, Erzincan Binali Yildirim University, Erzincan, Turkey
Abstract
Purpose – The purpose of this paper is to create and analyze the effectiveness of a new runway system, which is totally created for the future free
route operations.
Design/methodology/approach – This paper researches and analyses the new generated runway concept with the fast time simulation method.
Fuel consumption and environmental effect of the new runway system are calculated based on simulation results.
Findings – According to different traffic density analyses the Omnidirectional Runway with Infinite Heading (ORIH) reduced fuel consumption and
CO2 emissions up to 46.97%. Also the total emissions of the ORIH concept, for the hydro carbon (HC), carbon monoxide (CO) and nitrogen oxides
(NOx) pollutants were lower than the total emissions with the conventional runway up to 83.13, 74.36 and 51.49%, respectively.
Practical implications – Free route airspaces bring many advantages to air traffic management and airline operations. Direct routes become
available from airport to airport thanks to free route airspace concept. However, conventional single runway structure does not allow aircraft
operations for every direction. The landing and take-off operations of a conventional airport with a single runway must be executed with only two
heading direction. This limitation brings a bottleneck direct approach and departure route usage as convenient with free route airspace concept. This
paper suggests and analyzes the omnidirectional runway with infinite heading (ORIH) as a solution for free route airspace.
Originality/value – This paper suggests a new and futuristic runway design and operation for the free route operations. This paper has its
originality from the suggested and newly created runway system.
Keywords Airport, Air traffic management, Fast time simulation, Aircraft exhaust emissions
Paper type Research paper
excessive demand for air transportation, and these cause a drop
in the efficiency of the air transport system. This situation leads
researchers to study these topics to overcome these negative
effects and improve the efficiency of air transportation in a
number of ways: fuel consumption (Turgut et al., 2014; Singh
and Sharma, 2015; Sahin, 2019), delay reduction (Samà et al.,
2015; Cai et al., 2017) and the minimization of emissions (Tian
et al., 2018; Pawlak et al., 2021). These studies, generally, focus
on conventional route structures and runway configurations.
However, there are some innovative ideas, such as free route
airspace (FRA[1]) (EUROCONTROL, 2008) as a procedural
approach and the endless runway (ER) concept (Hesselink
et al., 2013), which are futuristic concepts to improve
efficiency. These ideas require radical changes in the
procedures of air traffic flow management. However, today’s
technology is developing to support ideas such as these, as a
result, the day when they will be in use is approaching.
The free route airspace concept focuses on whole airspace
operations through member states in the ECAC (European
Civil Aviation Conference). Owing to its flexibility on route
choice between two points in an airspace, aircraft fly with more
direct routes. Hence, this will enable FRA to reduce 500,000
1. Introduction
Air transportation is the preferred choice among passengers
especially for long travel distance at present, and, as a result, the
demand for air transportation is increasing day by day. The
growth forecast given by EUROCONTROL for the year 2040
shows that total Instrument Flight Rules (IFR) traffic in
Europe will increase to 16.2 million, which is 53% greater than
the total number of IFR movements in 2017
(EUROCONTROL, 2018). However, after COVID-19
pandemic, all forecasts had to been revised. According to this
revision, the traffic level of 2019 can be reached again in 2024
(best case scenario), 2025 (mid case scenario) and 2029 (worst
case scenario). (EUROCONTROL, 2021a, 2021b) The
increasing demand on air transportation creates congestion in
airspace sectors and, likewise, at airports. This increase brings
some negative effects, such as environmental issues (noise,
emission, etc.), capacity problems and delays related to the
The current issue and full text archive of this journal is available on Emerald
Insight at: https://www.emerald.com/insight/1748-8842.htm
Aircraft Engineering and Aerospace Technology
94/7 (2022) 1180–1187
© Emerald Publishing Limited [ISSN 1748-8842]
[DOI 10.1108/AEAT-09-2021-0283]
Received 20 September 2021
Revised 11 December 2021
Accepted 8 February 2022
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nautical miles, 3,000 tons of fuel, 10,000 tones CO2 emissions
and e3m in fuel cost savings in a day after it is fully
implemented at European level (EUROCONTROL, 2008).
These improvements depend on predictions for an optimistic
scenario.
The ER concept aims to redefine airports and the runway as
a circle to improve air traffic flow at airports. ER supports
simultaneous airport operations with a new runway design.
Three aircraft may take off and land at the same time on an ER
(Dash et al., 2019). Additionally, it reduces delays and
emissions because it shortens taxi duration and eliminates abort
take-off and runway overruns (Chakraborty et al., 2020).
Despite these advantages, there are some disadvantages of this
concept, such as load factor during turning on the runway and
the requirement of a new aircraft design that supports the
circular runway concept.
It is clear that the future of air transportation will require
more direct routes and reduced carbon footprints. The ECAC
states should modify the approach procedures as convenient for
FRA in their airspace to take full advantage of FRA in the near
future. Full implementation of FRA will lead to more direct
routes in the en-route flight phase and even during approach.
Furthermore, concepts such as the endless runway should be
accelerated to help gain the full benefits of FRA
implementations. However, the aforementioned problems, of
load factors when turning on the ER and the requirement of a
new aircraft design to provide safe operations on ER, are still
significant millstones that will need to be overcome before the
endless runway concept can be implemented in the air
transportation system. In this study, the main idea behind the
ER concept is modified to define a new runway concept to
overcome the disadvantages and to provide the ability to use a
runway for landing and take-off operations from all directions.
It is called the Omnidirectional Runway with Infinite Heading
(ORIH) and uses the conventional runway shape. This paper
will introduce the concept of ORIH to support FRA operations,
and it enables airline operators to use runways in a way that is
far more similar to conventional procedures instead of the
challenging procedure of using ER, which require turning
during landing and take-off.
In the remainder of this article, previous studies about FRA
and ER will be given and then the concept of ORIH will be
introduced. A model and simulation of ORIH in the Airport
and Airspace Simulation Model (SIMMOD) tool, together
with its results, will be presented and compared with a
conventional runway for its approach and departure routes.
The operation times, fuel consumption, and exhaust emissions,
to consider the environmental impact, of the ORIH concept
and a conventional runway are then analyzed and compared in
the results and discussion section. Finally, the limitations of this
study and directions for future work are presented.
(ACCs) in Europe will have fully implemented the FRA
concept (EUROCONTROL, 2021a, 2021b). A number of
studies have been carried out on the implementation of FRA
(Nava Gaxiola and Barrado, 2016; Gaxiola et al., 2018; Vagner
and Ferencova, 2018; Pérez-Castan et al., 2020). Gaxiola et al.
(2018) and Pejovic et al. (2019) studied the deployment of
FRA in the Northern European FRA in terms of safety
concerns. The results of Gaxiola et al. (2018) show that the
FRA deployment in the North of Europe would not make a big
change in safety in terms of two indicators: loss of aircraft
separation and airspace complexity. In another analysis in the
Northern European Free Route Airspace was carried out by
Pejovic et al. (2019), in which their aim was to analyze the effect
of cross border FRA implementation in terms of safety
performance. The results show that FRA implementation
reduces the potential loss of separation by 35%. Additionally,
there have been some studies carried out for the Southwest
Functional Airspace Block (FAB). One case study by Xie et al.
(2017) showed that the implementation of FRA may reduce
the workload of controllers in the Manila FIR. However, Bruno
et al. (2018), who carried out a study on the work of 34 air
traffic controllers in the Zagreb Area Control Centre, stated
that controllers’ workload increased with the FRA
environment. As has been stated earlier, FRA uses direct routes
between two points in an airspace; therefore, it is important to
compare its benefits to traditional route-based operations.
Kuenz (2018) compared direct route operations to route-based
operations and evaluated the potential benefits of the
implementation of the free route concept. The results show that
the FRA implementation reduced the average route distance by
more than 9% when compared to route-based operations. This
is another valuable outcome of FRA in addition to its safety
performance that was discussed in Gaxiola et al. (2018) and
Pejovic et al. (2019). It is clear that FRA implementation has
some benefits in reducing flight distance with more direct
routes, which leads to lower fuel consumption, reduced carbon
footprints of the aircraft and lower costs for airlines in terms of
both money and time. Moreover, it reduces the loss of
separation among aircraft, but there are different conclusions
concerning controller workload.
Enhancing the airspace capacity with more direct routes
through the use of FRA is not enough to enhance the overall
capacity. Airport runway capacities should also be considered
and enhanced. In addition to new procedures, such as the FRA
implementation, there are some innovative ideas to improve
airport runway capacity. One of these innovative ideas is the
ER. The ER is a new runway concept that aims to overcome the
effect of wind changes, especially tailwind and crosswind.
Hence, Hesselink et al. (2013) presented this new runway
concept that enables aircraft to land/take off from/in any
direction. This will help aircraft shorten their global trajectory
since this new concept always enables aircraft to operate with a
headwind. Because the shape of the runway is a circle, there is
also no concern about runway overrun. The ER is expected to
be used at large airports to enable the runway to handle a
sufficient number of operations, two candidates are Roissy
Charles de Gaulle and Palma de Mallorca. The researchers also
conducted some simulation studies to test the ER concept and
determine the level of compatibility with the current aircraft
design. Hesselink et al. (2013) and Dupeyrat et al. (2014)
2. Related work
The concept of FRA was defined by EUROCONTROL, and it
supports more direct routes in air traffic flow to reduce delays,
fuel consumption, and the carbon footprints of aircraft
(EUROCONTROL, 2008). In total, 55 area control centers
either fully or partially implemented FRA by the end of 2019.
At the end of 2030, it is expected that all Area Control Centers
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underlined some concerns about the possible implementation
of the ER at the present time. If aspects such as terminal
buildings and passenger areas are overlooked, there are two
main concerns about the ER concept. The first of these is the
effect of load factor during accelerating/decelerating on the
runway due to the banked and circular runway. Load factor is
the same as the load factor when an aircraft is turning left/right
in the air, and this will affect the aircraft dynamics and
passenger comfort on the aircraft. Even though some
simulation experiments made by these researchers (Hesselink
et al., 2013; Dupeyrat et al., 2014), it is still a concern in terms
of lateral and axial load on the gear during manual piloting
(Chakraborty et al., 2020). The second issue that was also
underlined in Hesselink et al. (2013) is the non-negligible risk
of contact between the outer engine and the banked and
circular runway. It is also another negative side of the ER
concept especially as it depends heavily on the pilot’s skills. The
take-off/landing field length was also evaluated as being longer
than the conventional length in the same research. It has been
mentioned in Dupeyrat et al. (2014) that some key features of
aircraft design need to change to be compatible with the ER
concept, these are connected with the fuselage, wingspan,
location of engines and the control surfaces. However, some of
these requirements are opposite to the expected future of
aircraft design that is expected to have a higher aspect ratio as
stated in Hesselink et al. (2013).
When all the studies and concerns of the ER concept have
been evaluated in detail, it is clear that this concept would be
able to remove tailwind and crosswind problems, however, it
would also create some problems especially related to areas
such as aircraft performance, piloting skills, passenger comfort
and the complexity of runway structure, which is banked and
circular runway. Therefore, in this study, we aimed to develop a
new runway concept which supports landing/take off in every
direction on a flat runway surface which eliminates the
disadvantages of the banked and circular runway.
In the following section, the proposed runway design, the
ORIH, will be introduced and then a comparison between the
performance of a conventional runway and the ORIH will be
given.
Figure 1 Single runway airport
The ORIH enables the airport to serve all directions. Hence, it
may present some solutions to solve the heading limitation
problem and work harmoniously with FRA. Furthermore,
airline companies will be able to continue to operate the same
fleet as today without the concerns of ER requirements. This
prevents the additional costs to upgrade the fleet for the airline
operators. The fleet upgrade or change cost includes not only
the aircraft costs but also the aircraft related costs such as
operation and maintenance tools, and costs for the
maintenance technician and their training for new fleet etc.
This is one of the most useful advantages of the ORIH. The
ORIH concept and expected connections between the runway
and the terminal are shown in Figure 2.
The ORIH is a 360-degree runway, which can overcome
wind uncertainty during any day or operations. The ORIH
allows multiple and infinite approach and take-off directions
supporting the future FRA airspace concept. This type of
runway would be 3000-m wide and 3000-m long in order for it
to be used in any direction that the wind allows aircraft to
operate. It would be designed as a flat surface to overcome the
banked runway problems found with the circular runways. As
the wind direction may change dynamically, four groups of
gates would be built to serve aircraft landed from any direction.
It is expected that all landing aircraft would taxi to the closest
available gates. One of the benefits of ORIH will be shorter taxi
distance, which results in a considerable decrease in fuel
consumption while taxiing, which also results in a reduction of
carbon emissions during the approach, rolling and taxiing
phases. However, this benefit is only possible if there is an
available gate, which has the shortest distance from runway exit
point. An important step is to determine the terminal area that
would serve the passengers. With ORIH, the terminal buildings
would be constructed four different blocks to decrease the
passenger transfer time for each approach direction from gates
to terminal buildings. After parking an aircraft, the passengers’
connection from gate to the related terminal building would be
made by an electric bus/tram system to support effectiveness
3. The omnidirectional runway with infinite
heading
Conventional runways allow landing and take-off operation of
aircraft for only two headings because of their rectangular
shape. Even for multiple runway configuration such as two
perpendicular crossing runways, the arrival and departure
directions are limited with the constructed runways headings.
This brings capacity problems and usage limits of the runway
under crosswind conditions and cannot be used at all when
there are heavy crosswinds. The two runway headings require
Standard Instrument Departure (SID) and Standard Terminal
Arrival Route (STAR) procedures to merge air traffic to proper
fix points according to approach or take-off directions. The
usage limitation of conventional runways using only these two
headings prevents the full advantage of FRA for all directions
from being realized. An example illustration for a single runway
airport can be seen in Figure 1.
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Figure 2 The omnidirectional runway with infinite heading, gates and terminal area connections
and greener airports. The expected benefits of this runway
design are summarized in Expected benefits of the ORIH
concept:
ORIH will enable more direct routes, from airport to
airport. Hence, it will support the future trend of the free
route airspace concept in Europe and it will reveal the full
advantages of FRA.
ORIH shortens approach and departure routes by
allowing take-off and landing operations for all headings.
It will reduce the fuel consumption of aircraft, and so
reduce exhaust emissions.
The environment of the airport will be more eco-friendly
according to emission level.
Contrary to the ER concept, ORIH will require no specific
aircraft designs or procedural difficulties.
becomes shorter with ORIH. The taxi times for departure
aircraft are also decreased with the ORIH concept. Therefore, a
decrease in the amount of approach and taxi distance results in
less fuel consumption and emissions. The decrease in fuel
consumption brings not only economical savings but also
environmental protection. It will support the use of the same
aircraft design that is used, as there is no need to make
structural changes to the aircraft.
ORIH and a conventional airport with a single runway were
modeled and analyzed in SIMMOD, this is presented in the
following section. ORIH and the conventional airport
configuration were compared with the same traffic mix in terms
of approach distance, approach duration, taxiing duration, fuel
consumption and exhaust emissions.
The FRA route structure will be allowed to continue without
any interruption caused by the SID or STAR requirements of
the conventional runway concept which aim to merge aircraft
into a common fix in the direction of the runway headings.
With ORIH, aircraft can take off and land using the most
suitable heading depending on their flight route. This presents
a twofold advantage to the system; it shortens the duration of
approach and sustains the FRA concept which is expected to be
in use by the end of 2030. It allows the chance to approach from
any direction that the wind enables; hence, it reduces approach
distance and removes the additional maneuver to align to the
runway heading. After landing, the aircraft taxi distance
4. Fast-time simulation modeling
Fast-time simulation models of the ORIH structure and the
conventional airport with a single runway were carried out in
the SIMMOD Fast Time Simulation environment. The
conventional airport was modeled as a baseline scenario with a
single runway configuration with 16 available gates at the
terminal building. Figure 3 shows the structure of the modeled
conventional airport. The ORIH was modeled as an alternative
scenario using the same entry and exist locations as the baseline
scenario. Even though the ORIH concept can be used with
infinite headings, it was modeled with only 32 different
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The route structure of both models can be seen in Figures 6
and 7. There are 16 entry and exit points located at the same
coordinates for both models. The route structure was
configured based on conventional SID and STAR procedures
for the conventional airport. The arrival and departure
routes for runway 36 were modeled as shown in Figure 6. The
ORIH concept has much more convenient and direct routes
from/to entry/exit points thanks to its infinite heading property.
As it can be seen in Figure 7, direct routes were modeled for
each 16 entry and exit points. In this way, arrival traffic directly
starts its approach procedure after their enroute phase with the
same heading used in their free route plan. Similarly, departure
traffic can use the most appropriate heading to allow them to
use the free route plan more efficiently owing to the advantages
of the ORIH concept.
Arrival and departure traffic density and distribution were
generated for three different analyses. Analysis 1 includes 16
arrival and 16 departure traffic that were uniformly distributed
for the entry points. Analysis 2(3) includes 64 arrival and 64
departure traffic that were uniformly (exponentially)
distributed for the entry points. For each analysis the chosen
aircraft type for all flights was the Boeing 737–800 whose
engine is CFM56-7 series engines to eliminate the impact of
Figure 3 Conventional runway
headings for analysis because of modeling limitations. The gate
and terminal building locations for the ORIH structure are the
same as defined for the concept in Figure 2. The modeled
airport and runway structure of the ORIH can be seen in
Figure 4. The illustration that shows the gates and taxiways of
the ORIH can be seen in Figure 5.
Figure 6 Conventional route structure
Figure 4 The ORIH concept
Figure 7 The ORIH concept route structure
Figure 5 Gate and taxiways configurations of the ORIH
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aircraft performance among different scenarios. Each arrival
flight continued as a departure after the deboarding and
boarding process. During the simulation, the traffic used all 16
different entry and exit points. The entry points of the arrival
flights were also used as the exit points for the subsequent
departure. It was planned that each departure would return
using the same point as it had entered during its arrival phase.
All other parameters, except the route structure, runway
configuration and gate locations, were modeled identically for
the baseline and the alternative scenarios. The number of gates
for each scenario were assumed to be enough to meet the total
traffic demand.
Table 2 shows the total amount of emissions at the airport
when using the ORIH concept and a conventional runway for
different scenarios. The total amount of each pollutant is given
in kilograms, and HC, CO and NOx were selected to represent
performance in terms of emission. All calculations of emissions
were completed according to the ICAO aircraft engine
emission database (ICAO, 2021) and equation (2) (ICAO,
2015), given by the ICAO. TIM, FF, EI and Ne represent time
in mode, fuel flow, emission index and number of engines
respectively. The indices i, j and k represent pollutant, aircraft
and aircraft operation mode, respectively. TIM (min)
corresponds to the total duration of all aircraft and was
provided by the SIMMOD results. It covers the duration in the
phases of approach and taxi-in, for arrivals and taxi-out for
departures. FF (kg/sec) and EI (g/kg) were obtained from the
ICAO aircraft engine emission database for the appropriate
engine type of the aircraft used in the SIMMOD simulation.
The FF and EI values that were used in calculations can be seen
in Table 3.
The emission calculations for the arrivals include the final
approach and taxi-in phases. Emission calculations for
departure include taxi-out phase:
5. Results and discussion
The fast-time simulation results were used for fuel
consumption and exhaust emission analysis and calculations.
Fuel consumption calculations were performed according to
Base of Aircraft Data (BADA) fuel consumption calculation
methods as it is shown in the equation (1). In this equation h
represents the altitude in feet, Cf3 and Cf4 represent the 1st and
2nd descent fuel flow coefficients in (kg/min) and (feet),
respectively. The calculations were carried out for every 100
feet cumulatively from top of descent to touchdown. The
consumed fuel for each 100 feet level were calculated with
multiplication of fmin with descent duration of that 100 feet.
The CO2 emission calculations were carried out by multiplying
the fuel consumption with 3.16 (ICAO, 2018). The total
consumed fuel and the CO2 emissions for the ORIH concept
and the conventional runway configuration can be seen in
Table 1:
h
(1)
fmin ¼ Cf 3 1 Cf 4
Eij ¼
X
ðTIMjk 60Þ FFjk EIijk Nej
The enhancement of the emission is decreasing with the
increasing traffic density and distribution among the Analysis 1
to 3. It is clear that the ORIH concept is better than the
conventional runway in terms of emission in Analysis 1 and
Analysis 2. However, in Analysis 3, the departure emission
values for the ORIH is worse than the conventional runway.
The main reason for that is the increasing departure queue
waiting times for the ORIH with the exponentially distributed
traffic demand.
The fuel consumption and emission enhancements achieved
by using an ORIH system mainly result from the free route
adaptability of the ORIH concept. All traffic can choose and
use the most appropriate runway heading from the infinite
headings available with the ORIH concept in contrast to
the single runway heading with a conventional runway. These
enhancements make the ORIH concept an innovative future
solution for the future free route concept with its
environmentally friendly operations.
The ORIH concept reduced fuel consumption and CO2
emission for Analysis 1, Analysis 2 and Analysis 3 by 46.97,
44.77 and 16.08%, respectively. This means that a
considerable amount of fuel can be saved by taking advantage
of ORIH. This reduction in fuel consumption as a result of
using the ORIH concept support the goal of decreasing the
total aircraft emissions at airports. The amount of emissions at
the airport, comparing the use of the ORIH concept and a
conventional runway are given in the following table.
Table 1 Fuel consumption and CO2 emissions for the approach phases of the ORIH and conventional runway
Analysis 1
Total fuel consumption, kg
CO2, kg
Analysis 2
Total fuel consumption, kg
CO2, kg
Analysis 3
Total fuel consumption, kg
CO2, kg
The
ORIH
Conventional runway
1453.00
4591.48
The
ORIH
6184.00
19541.44
The
ORIH
8841.00
27937.56
2740.00
8658.40
Conventional runway
11198.00
35385.68
Conventional runway
10536.00
33293.76
1185
Enhancement
(%)
46.97
Enhancement
%
44.77
Enhancement
%
16.08
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Volume 94 · Number 7 · 2022 · 1180–1187
Table 2 Emission values of ORIH and the conventional runway
Analysis
Arrivals
Analysis 1
Conventional runway
The ORIH
Enhancement %
Analysis 2
Conventional runway
The ORIH
Enhancement %
Analysis 3
Conventional runway
The ORIH
Enhancement %
HC, kg
7.24
1.22
83.15
HC, kg
29.00
4.96
82.90
HC, kg
28.75
5.28
81.64
Departures
CO, kg
107.86
27.66
74.36
CO, kg
434.08
115.01
73.50
CO, kg
424.94
144.00
66.11
NOx, kg
57.39
27.84
51.49
NOx, kg
233.96
118.26
49.45
NOx, kg
221.59
167.29
24.50
HC, kg
4.46
0.95
78.63
HC, kg
25.38
8.78
65.41
HC, kg
21.09
25.29
-19.93
CO, kg
50.30
10.75
78.63
CO, kg
286.21
99.01
65.41
CO, kg
237.88
285.29
-19.93
NOx, kg
4.41
0.94
78.61
NOx, kg
25.11
8.69
65.41
NOx, kg
20.87
25.03
-19.93
Table 3 Emission index and fuel flow coefficients (ICAO, 2021)
HC EI App
(g/kg)
0.08
HC EI Idle
(g/kg)
CO EI App
(g/kg)
CO EI Idle
(g/kg)
NOx EI App
(g/kg)
NOx EI Idle
(g/kg)
Fuel Flow App
(kg/sec)
Fuel Flow Idle
(kg/sec)
3.84
5.03
43.31
8
3.8
0.268
0.094
6. Limitations and future work
with the ORIH concept. Also, the safety concern for
overflying the terminal buildings must be studied in the
further researches.
For future work, solutions can be investigated to solve these
aforementioned limitations of the ORIH concept.
As well as the listed and analyzed advantages of the ORIH
concept, there are also some limitations of its implementation.
First and foremost is the environmental effects of the ORIH
construction. The ORIH requires a huge construction area
which is about 9 km2 for only runway surface area. This
required area brings high constructional and operational costs.
Also, it affects the habitat around the ORIH. Another
limitation is the wind concern with ORIH. Even though the
ORIH concept supports the use of infinite headings, the wind
direction and speed are the main concern for operational ATC
procedures. Over limit wind speeds can enforce some
limitations for the determination of usable headings with the
ORIH concept for operations. As a result, ORIH becomes
similar to generic runway due to wind concerns. However, as is
one of the main benefits of ORIH, there is no crosswind
concern because of the infinite runway headings that it offers.
The ORIH concept allows the use of the runway with any wind
direction as the runway configuration can easily be planned and
changed according to the wind direction, unlike a conventional
runway.
Navigation equipment and their working principles are other
limitations of the ORIH concept. As there are multiple and
infinite runway headings that can be used, navigation
equipment must be redesigned to support the operation of the
ORIH concept, in particular directional guidance equipment
such as ILS, VOR and DME must be developed to support the
ORIH concept.
ATC procedures and applications must also be redesigned
according to the principles of the ORIH concept, such as
separation methods, separation minimums, infinite heading
runway usage, arrival and departure routes.
The physical infrastructure is another limitation of the
ORIH concept. The location of gates, runway markings and
lighting, taxiway markings and lighting, terminal buildings
and other similar facilities must all function conveniently
Note
1 FRA stands for “Free Route Airspace” in the remaining of
the paper
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Further reading
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(BADA) revision 3.6 EUROCONTROL”, (September
2004).
Corresponding author
Emre Aydo
gan can be contacted at: emreaydogan@
eskisehir.edu.tr
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