U.S. patent application number 10/059766 was filed with the patent office on 2002-08-22 for airplane ground location methods and systems and airplanes.
Invention is credited to Sadler, Lance Richard.
Application Number | 20020116127 10/059766 |
Document ID | / |
Family ID | 24841252 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020116127 |
Kind Code |
A1 |
Sadler, Lance Richard |
August 22, 2002 |
Airplane ground location methods and systems and airplanes
Abstract
Airplane ground location methods and systems are described.
Airplane ground location methods and systems are described. In one
embodiment, ground locations for one or more airplanes are
electronically determined and a determination is made as to whether
there is a likelihood of a runway incursion based on determined
locations. In yet another embodiment, one or more airplanes have
one or more transmitters that are configured to wirelessly
communicate with one or more interrogators positioned about an
airfield. The transmitters are configured to transmit, while its
associated airplane is on the ground, wireless communication that
can be used by a computer to ascertain locations of associated
airplanes and determine, based on the locations, whether there is a
likelihood of a runway incursion between airplanes that are also on
the ground.
Inventors: |
Sadler, Lance Richard;
(Spokane, WA) |
Correspondence
Address: |
Lance R. Sadler
2014 E. Westminster Lane
Spokane
WA
99223
US
|
Family ID: |
24841252 |
Appl. No.: |
10/059766 |
Filed: |
January 28, 2002 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10059766 |
Jan 28, 2002 |
|
|
|
09707329 |
Nov 6, 2000 |
|
|
|
6381541 |
|
|
|
|
Current U.S.
Class: |
701/301 ;
340/961; 342/29 |
Current CPC
Class: |
G08G 5/0013 20130101;
G08G 5/0043 20130101; G08G 5/045 20130101 |
Class at
Publication: |
701/301 ;
340/961; 342/29 |
International
Class: |
G08G 005/04 |
Claims
1. An airplane ground location method comprising: receiving
wireless communication from one or more airplanes that are located
on the ground at an airfield; processing the wireless communication
with one or more computers to ascertain the location of
communicating airplanes; and determining whether there is a
likelihood of a runway incursion.
2. The method of claim 1 further comprising displaying indicia
associated with the locations of the airplanes on the ground.
3. The method of claim 1 further comprising polling one or more
airplanes on the ground and, responsive to said poling, receiving
wireless communication from the one or more airplanes from which
airplane locations can be determined.
4. An airplane ground location method comprising: electronically
determining ground locations for one or more airplanes on the
ground at an airfield; and determining whether there is a
likelihood of a runway incursion based on the determined
locations.
5. The method of claim 4 further comprising if there is a
likelihood of a runway incursion, implementing a remedial measure
to reduce the likelihood of a runway incursion.
6. The method of claim 5, wherein said act of implementing is
performed by a computer.
7. The method of claim 4, wherein said act of electronically
determining comprises receiving wireless communication from the one
or more airplanes and using the communication to determine ground
locations.
8. The method of claim 7, wherein said act of receiving wireless
communication is performed using a single interrogator that is
configured to receive the communication from the airplanes.
9. The method of claim 7, wherein said act of receiving wireless
communication is performed using multiple interrogators that are
configured to receive the communication from the airplanes.
10. The method of claim 9, wherein said multiple interrogators are
positioned along active runways and taxiways.
11. The method of claim 4, wherein said act of electronically
determining comprises transmitting wireless communication to the
one or more airplanes and, responsive to said transmitting,
receiving wireless communication from the one or more airplanes and
using the received wireless communication to determine ground
locations.
12. The method of claim 11, wherein said act of transmitting
wireless communication is performed using a single interrogator
that is configured to poll the airplanes.
13. The method of claim 11, wherein said act of transmitting
wireless communication is performed using a multiple interrogators
that are configured to poll the airplanes.
14. The method of claim 13, wherein said multiple interrogators are
positioned along active runways and taxiways.
15. The method of claim 4, wherein said act of determining the
likelihood of a runway incursion comprises doing so
electronically.
16. One or more computer-readable media having instructions which,
when executed by one or more computers, cause the one or more
computers to implement the method of claim 4.
17. A system comprising: one or more airplanes; one or more
transmitters, individual transmitters being disposed on individual
airplanes; said one or more transmitters being configured to
wirelessly communicate with one or more interrogators positioned
about an airfield; said one or more transmitters being configured
to transmit, while its associated airplane is on the ground,
wireless communication that can be used by a computer to: ascertain
locations of associated airplanes; and determine, based on the
locations, whether there is a likelihood of a runway incursion
between airplanes that are also on the ground.
18. The system of claim 17, wherein said one or more transmitters
comprise one or more transceivers.
19. The system of claim 18, wherein said one or more transceivers
are configured to be polled by the one or more interrogators.
20. The system of claim 18, wherein said one or more transceivers
are configured to be polled by the one or more interrogators, the
interrogators being positioned about the airfield's runway(s).
Description
RELATED APPLICATIONS
[0001] This is a continuation application of, and priority is
claimed to U.S. patent application Serial No. 09/707,329, the
disclosure of which is incorporated by reference herein
TECHNICAL FIELD
[0002] This invention relates to runway collisions avoidance
systems, and more particularly, to systems and methods for
detecting the presence and location of aircraft on the ground on
and near airport runways.
BACKGROUND
[0003] In 1991, a commuter plane taxied onto a runway that was
supposed to be clear for landings. In the maze of planes,
controllers didn't see it and neither did the pilot of an incoming
jetliner. The two planes collided in a sea of crunching metal. In
January of 1997, a DC-9 that was cleared to land at
Cleveland-Hopkins International Airport on runway 5R noticed a
commuter plane taxi into it path The pilot of the DC-9 was able,
just in time, to abort the landing and avoid colliding with the
commuter plane. That near miss, known in aviation language as a
"runway incursion", was caused by simple pilot confusion. The
commuter's pilot had become confused, taken a wrong turn, and
strayed onto the wrong runway. In the Fall of 2000, a Singapore
Airlines jumbo jet crashed in Taipei during a heavy rainstorm. The
plane had apparently tried to take off on the wrong runway and
slammed into construction equipment being used to repair the strip
The jetliner crashed killing 81 of the 179 people aboard Flight
SQ006 from Taipei to Los Angeles.
[0004] These are just three examples of a large number of runway
incursions that happen every year. In two instances, the incursion
was deadly, in another, loss of life was avoided only because of a
pilot's alert reaction.
[0005] One additional variable that adds to the possibility of a
runway incursion is the visibility at the time of the incursions.
Specifically, rain and fog can obscure pilot visibility thus
increasing the chance of a mishap on the ground. Human factors can
also contribute to ground mishaps. For example, perhaps an air
traffic controller inadvertently gives erroneous instructions to a
pilot, or, perhaps a pilot misunderstands the instructions or takes
a wrong turn
[0006] Whatever the cause, the potential loss of life due to runway
incursions is huge. Such incursions are potentially devastating
because of the numbers of passengers involved--two sets of
passengers, one from each plane. During the late 1990's, runway
incursions increased some 50%, according to at least one source.
The problem of runway incursions will necessarily continue grow as
air traffic in airports is expected to double in the coming
years.
[0007] Accordingly, this invention arose out of concerns associated
with providing systems and methods for detecting the presence of
and locating aircraft on the ground at airports.
SUMMARY
[0008] Airplane ground logon methods and systems are described. In
one embodiment, wireless communication is received from one or more
airplanes that are located on the ground at an airfield. The
wireless communication is processed with one or more computers to
ascertain the location of communicating airplanes and a
determination is made as to whether there is a likelihood of a
runway incursion.
[0009] In another embodiment, ground locations for one or more
airplanes are electronically determined and a determination is made
as to whether there is a likelihood of a runway incursion based on
determined locations.
[0010] In yet another embodiment, one or more airplanes have one or
more transmitters that are configured to wirelessly communicate
with one or more interrogators positioned about an airfield. The
transmitters are configured to transmit, while its associated
airplane is on the ground, wireless communication that can be used
by a computer to ascertain locations of associated airplanes and
determine, based on the locations, whether there is a likelihood of
a runway incursion between airplanes that are also on the
ground.
BRIEF DESCRIPTON OF THE DRAWINGS
[0011] FIG. 1 is an overhead view of an exemplary airfield in which
the described embodiments can be employed
[0012] FIG. 2 is an overhead view of an exemplary airfield in which
the described embodiments can be employed.
[0013] FIG. 3 is a block diagram of an exemplary system in
accordance with one described embodiment.
[0014] FIG. 4 is a block diagram of an exemplary location
transceiver that can be utilized in connection with one or more
described embodiments.
[0015] FIG. 5 is an overhead view of an exemplary airfield in which
the described embodiments can be employed
[0016] FIG. 6 is an overhead view of an exemplary airfield in which
the described embodiments can be employed.
[0017] FIG. 7 is a flow diagram that describes steps in a method in
accordance with the described embodiment.
[0018] FIG. 8 is a table that describes one aspect of one or more
described embodiments.
[0019] FIG. 9 is a block diagram of an exemplary system in
accordance with the described embodiment.
[0020] FIG. 10 is an overhead view of an exemplary airfield in
which the described embodiments can be employed.
[0021] FIG. 11 is an overhead view of an exemplary airfield in
which the described embodiments can be employed.
[0022] FIG. 12 is a view of an exemplary display that can be
provided in accordance with one or more embodiments.
DETAILED DESCRIPTION
[0023] Exemplary Airport Facility
[0024] FIG. 1 shows an exemplary airport facility 10 that includes
a taxiway 12, an active runway 14 and an entry/exit way 16 through
which planes can ingress and egress the taxiway or active runway.
In the present example, a number of planes (undesignated) are lined
up on taxiway 12, with one plane 18 waiting on the so-called
hammerhead to take the active runway for takeoff. Another plane 20
is waiting on entry/exit way 16 to cross over to the taxiway 12. A
plane 22 is shown "on approach" and is about to land. Typically, in
this situation, all of the planes will hold their position until
plane 22 has landed and proceeded to a position where movement of
the other planes can resume. This, however, is not always the case.
Sometimes, a pilot, because of confusion, poor visibility,
erroneous instructions and the like, will venture into an area
where they should not be. This can have disastrous consequences as
in the case of the Singapore Airliner mentioned in the "Background"
section.
[0025] As an example, consider FIG. 2. There, plane 18 has ventured
onto the active runway 14 before plane 22 has been able to land. If
the pilot of plane 22 does not visually see plane 18 blocking its
path and take corrective action at the right time, a collision will
likely occur.
[0026] Air traffic controllers typically move aircraft around by
giving instructions on where the aircraft should proceed and when.
Thus, the air traffic controller would typically tell the pilot of
airplane 18 when it was time to take the active runway. If,
however, the pilot of airplane 18 or, one of the airplanes waiting
on the entry/exit way becomes disoriented, they can fail to follow
the controller's directions thus leading to disaster
[0027] Exemplary Ground Location System
[0028] FIG. 3 shows a high level view of a ground location system
generally at 300 in accordance with one embodiment and includes one
or more location transmitters or transceivers 302-306, and a ground
location evaluator 308. In the illustrated example, location
transmitters or transceivers 302-306 are shown to be mounted on,
other otherwise incorporated in airplanes. Ground location
evaluator 308 includes, in this example, one or more receivers or
interrogators 310 that are configured to either or both of receive
communication from one or more of the location transmitters or
transceivers 302-306, or send and receive communication from the
location transmitters or transceivers. Evaluator 308 also includes
one or more processors 312, e.g. microprocessors, memory 314, a
database 316, and one or more displays 318. All of these components
can be operably coupled together for communication via a suitable
bus (not specifically designated).
[0029] In one embodiment, aspects of the methods that are described
below are implemented, at least in part, by software modules or
programs stored in memory 314 and executable on processor(s) 312.
To this extent, the invention includes all forms of
computer-readable media that can contain instructions thereon
which, can executed by one or more processors. Such media includes,
without limitation, ROM, RAM, CD ROMs, floppy disks, and the
like.
[0030] Each location transmitters or transceiver is preferably able
to wirelessly communicate with the ground location evaluator 308
and can provide information as to its location on the ground about
the area of the airport, or information that can be used by the
ground location evaluator 308 to derive an accurate location. Each
location transmitters or transceiver can have a unique ID so that
the location evaluator 308 knows which entity (e.g. aircraft) is
sending the communication
[0031] Any suitable type of transmitter, transponder or transceiver
can be used to implement location transmitters or transceivers
302-306.
[0032] For example, each location transceiver 302 can include
circuitry such as described in U.S. Pat. Nos. 5,914,671, 6,101,375,
6,097,301, 6,078,791, 6,045,652, 6,024,285, 6,013,949, 5,983,363,
and 5,974,078 and incorporated herein by reference. The devices
302-306 can be implemented as intelligent radio frequency
identification devices or remote intelligent communications (RIC)
devices which communicate at microwave frequencies.
[0033] FIG. 4 shows but one example of a device 302, in the form of
an intelligent radio frequency identification device integrated
circuit 400. The integrated circuit 400 includes a transmitter, a
receiver, a microprocessor, and a memory. The housing for the
device 302 shown in FIG. 4 can be any suitable housing made of any
suitable material. The device 302 further includes a send/receive
antenna 401 coupled to the integrated circuit 400. Any suitable
antenna can be used. Exemplary antennas are described in one or
more of the U.S. Patents incorporated by reference above. Each
device 302 can be powered by a power source that is on-board the
vehicle on which it is mounted. Alternately, the device 302 can be
battery powered. Examples of suitable battery powered devices are
described in U.S. Pat. No. 5,914,671, the disclosure of which is
incorporated by reference.
[0034] In principle, transmitters on each airplane, whether
implemented as transmitters, transceivers or the like, are able to
provide information or data pertaining to their location about the
runway. This information is electronically received by the ground
location evaluator 308 (FIG. 3) which then makes database entries
for each of the airplanes and analyzes the plane locations to
ascertain whether there is a likelihood of a runway incursion. The
ground location evaluator is also provided with information as to
the status of various inbound planes so that it can incorporate
those statuses into its evaluation, as will become apparent below.
The transmitter on each plane can be configured to provide its
information periodically, at regular intervals so that the ground
location evaluator can continually monitor the ground state or
location of each of the planes. Additionally, to visually assist
the air traffic controllers, a display (318) can be provided in the
control tower to indicate the location of various planes that are
being tracked by the system. This way, air traffic controllers can
ascertain, at a glance, where a potential incursion has been
identified by the system. This display can advantageously be a real
time display that is continually updated as the status or locations
of the ground-tracked planes changes.
[0035] Forbidden and Allowed Locations
[0036] In one embodiment, the concept of forbidden and allowed
locations is utilized. A forbidden location is a location which, as
computed by processor 312 and for a given airfield state, has a
high degree of likelihood of experiencing a runway incursion. An
allowed location is a location in which, for a given airfield
state, there is little or no likelihood of experiencing a runway
incursion. For each plane having a location transmitter or
transceiver, the information that is received by the ground
location evaluator 308 is processed and a determination is made as
to whether the airplane is in a forbidden or allowed location. If a
airplane is in a forbidden location, preventative measures can be
taken. Examples of this are given below.
[0037] Consider for example FIG. 5 which shows a runway in which
various so-called windows, forbidden locations and allowed location
have been designated. Consider also that there are typically two
periods of time when runway incursions are likely--on landing and
on take off. For each designated window there are associated
forbidden and allowed locations on the runway. If a subject plane
enters a particular designated window and another plane happens to
be positioned within a forbidden location for that window, then
preventative measures can be taken
[0038] As an example and in accordance with one embodiment,
consider the following: When a plane is on approach to land,
various windows are defined that can, at any one time, contain the
subject plane. As an example consider an approach window 500 and a
landing window 502. When a plane enters the approach window 500 it
is still in the air and is slated to land in a short period of
time. The approach window 500 might extend from the hammerhead to
1/4 mile out. When the approach window is occupied by a plane on
approach, a forbidden location 504 is defined and in which no other
planes are allowed to be located. The illustrated forbidden
location can extend from the hammerhead down the runway for any
suitable distance. In a very conservative implementation, the
forbidden location can extend the entire length of the runway so
that when a plane is within the approach window 500, no other
planes are allowed within the forbidden location 504. Alternately,
the forbidden location 504 can be defined to allow other planes to
cross the active runway at some distance down the runway. One of
the aspects of the inventive embodiments is that the various
windows and forbidden and allowed locations are adjustable to
accommodate different airport traffic conditions. For example, in
crowded airports the forbidden locations might be adjusted to
accommodate movement of the planes on the ground while planes are
within the approach window (albeit in a safe manner). In smaller
airports where traffic congestion is not a problem or issue, the
forbidden locations might be adjusted so that no other planes are
allowed to cross an active runway when a plane is within the
approach window.
[0039] Additionally, landing window 502 can be provided and is
defined when a plane has previously been within the approach window
500 on approach but has now touched down. When a plane is within
the landing window 502 after having been within the approach window
500, one or more forbidden locations can be defined on the runway.
For example, a forbidden location 506 can be defined to run the
entire length of the runway when a plane that has just landed is
within the landing window 502.
[0040] Consider also FIG. 6. There, a takeoff window 600 is
defined. The takeoff window is occupied by a plane when it takes
the active runway preparing for takeoff. When a plane is within the
takeoff window 600, one or more forbidden locations, such as
location 602 are defined and within which other planes are not
allowed to enter. It should be noted that the takeoff window 600
and the landing window 502 can have portions that coincide. In some
implementations, they may even constitute the same window differing
in name based only on the state of a plane just prior to entering
the window, e.g. if the state of the plane just prior to entering
the window was "In the approach window" then the window 600 is the
landing window. Alternately, if the state of the plane just prior
to entering window 600 was "on the ground", then the window is the
takeoff window.
[0041] FIG. 7 is a flow diagram that described steps in a method in
accordance with the described embodiment. The steps in this method
can be implemented in any suitable hardware, software, firmware, or
combination thereof. In one embodiment, the method is implemented,
at least in part, in software.
[0042] Step 700 defines one or more windows proximate a runway.
Exemplary windows are given above in the form of approach windows,
landing windows, and takeoff windows. It is possible, however, to
have other windows. For example, windows might be defined at a
lower level of granularity, e.g. there may be 2 or more sub-windows
within the landing window, or 2 or more windows within the approach
window. Step 702 defines one or more forbidden locations relative
to the window(s) that are defined in step 700. Step 704 defines one
or more allowed locations relative to the window(s) that are
defined in step 700. Exemplary forbidden and allowed locations are
given above. Step 706 determines the locations of one or more
planes on the ground. Examples of how this can be done are given
below. It is to be appreciated, however, that any suitable way of
determining the locations can be used. The plane locations can be
stored in a database, such as database 316 (FIG. 3). Examples of
how that can be done are given below. Step 708 determines whether
any planes are within any of the defined windows. If there are no
planes within the defined windows, the method can branch back to
step 706 to again determine the location of the planes on the
ground. By looping back to continually determine the locations of
the planes on the ground, the method can ensure that at all times
steps are being taken to maintain, as accurate as possible, the
location of every appropriate plane that is on the ground. If, one
the other hand, step 708 determines that there are one or more
planes within a window or windows, step 710 determines whether any
of the plane locations (determined by step 706) coincide with any
of the forbidden locations. If none of the plane locations coincide
with a forbidden location, the method branches back to step 706 to
determine again the locations of all of the planes. If, however,
step 710 determines that a plane location coincides with a
forbidden location, then step 712 can implement remedial
measures.
[0043] Exemplary Remedial Measures
[0044] FIG. 8 is a chart the describes exemplary remedial measures
that can be implemented when a plane location coincides with a
forbidden location and a different plane is within the window
associated with that forbidden location.
[0045] The first condition that might occur (condition 800) is that
the approach window is occupied by a plane on approach, and the
forbidden location is occupied by a plane on the ground. In this
instance the remedial measure can be to issue a "go around" command
to the plane on approach. Accordingly, the plane on approach will
not land and there will hopefully be enough time to rectify the
situation on the ground. Another condition that can occur is that
the landing window can be occupied by a plane while a forbidden
location is occupied by another plane (condition 802). In this
instance, there might be a couple of different remedial measures
that can be implemented depending on the state and location of both
planes. A first redial measure will be to issue a "clear active
runway" command immediately to the plane that is in the forbidden
location. Additionally, if the plane that has entered the landing
window just recently entered the landing window, i.e. say its
wheels just touched down, a "go around" command can be issued to
that plane within the landing window so that it can take off and go
around. A third condition that can occur (condition 804) can take
place when a plane enters the takeoff window and another plane is
within a forbidden location for the takeoff window. In this case, a
"clear active runway" command can be immediately issued.
Additionally, if the plane that has entered the takeoff window has
not yet begun its takeoff roll, the takeoff can be simply delayed
until the ground situation is cleared up. If the plane in the
takeoff window has just begun its takeoff roll, and it can safely
do so, it can abort its takeoff.
[0046] Single Interrogator Embodiment
[0047] In one embodiment, a single interrogator is provided and can
poll, at regular intervals, all of the location transceivers in the
appropriate operating environment. The location transceivers
receive the interrogation signal and then respond with information
that can be used by the ground location evaluator 308 to ascertain
the location of all of the appropriate airplanes on which the
transceivers are mounted. Alternately, the interrogator can be
configured as a passive interrogator (i.e. receiver) in that it
simply receives data that is transmitted from each transceiver or
transmitter at regular intervals.
[0048] FIG. 9 shows an exemplary system that can be utilized in a
passive interrogator embodiment. Location transmitter 304 is
coupled with a location provider 900 that is programmed to
determine, within a desired degree of precision, the location of
the airplane on the ground. Location provider can be any suitable
location provider that is capable of providing location
information. For example, the location provider might be
implemented by a GPS module that is able to triangulate position
based upon information received from satellites. Exemplary GPS
information is described in U.S. Pat. No. 5,894,266, the disclosure
of which is incorporated by reference above. Alternately, other
systems can be used. For example, such systems might be tied
directly to a plane's navigation instrumentalities.
[0049] As the location provider develops information as to its
location, transmitter 304 transmits such information to the ground
location evaluator 308 (FIG. 3). The ground location evaluator 308
then tracks the plane's location in database 316. As the ground
location evaluator 308 receives updates of the plane's location,
the database is updated. As information is received from the
various planes, processor(s) 312 process the information to
ascertain whether there is a likelihood of any ground incursions,
as described above.
[0050] In another so-called "active interrogator" embodiment, a
single interrogator is provided and actively interrogates planes to
ascertain their location on the ground. When a location transceiver
on a plane is interrogated by the interrogator 310 (FIG. 3), it
provides location information based upon the input from the
location provider 900 to the ground location evaluator 308, which
then processes the information to ascertain whether any problem
situations are likely to occur based upon the positions of the
other airplanes.
[0051] FIG. 10 diagrammatically illustrates a single interrogator
embodiment where a single interrogator 1000 is provided in or on
the control tower. As the interrogator interrogates the planes on
the airfield, each plane answers and transmits its location to the
interrogator.
[0052] Multiple Interrogator Embodiment
[0053] In another embodiment, multiple interrogators are provided,
each having zones within which they transmit and receive. The
interrogators monitor these zones by continually polling for any
planes that may have entered the zone. When a plane enters the
zone, its transceiver receives a transmitted signal from the
associated interrogator and transmits a reply. The reply can simply
only contain a unique identifier associated with that plane. This
is because the position of each interrogator is fixed and known.
Thus, any plane responding to a particular interrogator must be
within the interrogator's polling zone. The interrogators then
relay the identifiers of the planes within their zones to the
ground location evaluator 308 which can then track the planes as
described above.
[0054] Consider, for example, FIG. 11. There, multiple
interrogators 1100-1110 are shown positioned along the active
runway and the taxiway. Each of the interrogators can interrogate
an area within a defined zone. In this example, the zones are for
an interrogator are designated with the suffix "a". Thus, for
example, the zone associated with interrogator 1100 is designated
at 1100a, and so on
[0055] Air Traffic Controller Display
[0056] In one embodiment, a visual display is provided in the
control tower so that air traffic controllers can immediately
ascertain the state of the airfield at a given time. The display is
preferably integrated directly with the ground location evaluator
308 (FIG. 3) so that it displays, in a real time manner, the
current state of the airfield. The display is preferably a simple,
color-coordinated display that can immediately convey the state of
the airfield.
[0057] FIG. 12 shows an exemplary display 1200 which is similar in
appearance to the layout of the airfield as shown in FIG. 11.
Airplanes that are determined to be in allowed locations are
displayed as green lights, while airplanes that are determined to
be in forbidden locations are displayed as red lights. In the
illustrated example, one plane can be seen to be in a forbidden
location on the active runway. In this way the system provides a
two-fold safety system. First, the automated, electronic tracking
system automatically determines the state of the airfield at any
given instant in time. It is able, through continuous analysis, to
maintain up-to-the-minute information on the locations of airplanes
around the airfield. This then supplements an air traffic
controller's job of ensuring that ground safety is maintained. The
described system can increase response times by greatly reducing
the time between when a unsafe condition has occurred and when, in
fact, those individuals who need to be notified are notified.
Consider, for example, a situation on a foggy night when air
traffic controllers have a busy airfield with low visibility. The
present system does not depend on visibility in order for it to
keep track of the ground location of the airplanes for which it is
responsible. When a plane enters a forbidden location for a given
airfield state, the controllers can be immediately notified that
there is a condition that is likely to lead to a runway incursion
if a remedial measure is not put in place. If the controllers were
to rely only on their own visibility and the ability of the pilots
to accurately communicate their location and not get lost on the
runway, it might be too late for any remedial measures to be put in
place. The utility of the inventive systems and methods can most
recently be appreciated in light of the terrible tragedy of the
Singapore Airliner mentioned above. With the present system,
regardless of how the pilot came to be situated on the wrong
runway, this information would be automatically ascertained at the
instant the pilot entered an area where the plane should not be.
Second, by providing a simple visual display for the air traffic
controllers that quickly and accurately reflects the ground
location of all of the airplanes on the airfield, the controllers
can not only be notified of a potential problem, but can easily
ascertain, at a glance, where a violation of a forbidden location
has occurred. This can greatly increase remedial response
times.
[0058] Although the invention has been described in language
specific to structural features and/or methodological steps, it is
to be understood that the invention defined in the appended claims
is not necessarily limited to the specific features or steps
described. Rather, the specific features and steps are disclosed as
preferred forms of implementing the claimed invention.
* * * * *