Patent Publication Number: US-8977413-B2

Title: Methods for derated thrust visualization

Description:
BACKGROUND OF THE INVENTION 
     In contemporary aircraft, a pilot prior to flight may manually select a takeoff thrust for the engines of the aircraft being flown. Many takeoffs are done at full or rated thrust. When a takeoff is performed at less than full thrust, it is referred to as a derated takeoff. Such derated takeoffs involve the pilot actively selecting to perform a takeoff maneuver with less than full thrust to at least one of, and typically to all of, each aircraft engine available. Currently a majority of takeoff maneuvers that could be performed at derated thrust are performed at full thrust because the perceived risk of performing the maneuver at a derated thrust outweighs any perceived benefit. Pilots are currently developing such risk assessment based on anecdotal information or gut-feelings and at best a pilot may be presented with a text statement describing the amount of runway they will have left at the derated thrust setting. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, a method of illustrating a derated takeoff on a flight display in a cockpit of an aircraft includes displaying a runway representation on the flight display of a runway on which the aircraft is to takeoff and displaying a takeoff indicia referenced to the runway representation, with the takeoff indicia representing a location along the runway where the aircraft is airborne for a thrust setting, which is less than a full thrust setting. 
     In another embodiment, a method of illustrating a derated takeoff on a flight display in a cockpit of an aircraft includes displaying a runway representation on the flight display of a runway on which the aircraft is to takeoff, displaying a takeoff indicia referenced to the runway representation, with the takeoff indicia representing a location along the runway where the aircraft is airborne for a thrust setting, which is less than full thrust, and displaying a cost indicia corresponding to a takeoff at the thrust setting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view of a portion of an aircraft cockpit with a flight display on which a derated takeoff may be illustrated according to embodiments of the invention. 
         FIG. 2  is a schematic view of an illustration of a derated takeoff according to a first embodiment of the invention. 
         FIG. 3  is a schematic view of an illustration of a derated takeoff according to a second embodiment of the invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
       FIG. 1  illustrates a portion of an aircraft  10  having a cockpit  12 . While a commercial aircraft has been illustrated, it is contemplated that embodiments of the invention may be used in any type of aircraft allowing for derated engine thrust. A first user (e.g., a pilot) may be present in a seat  14  at the left side of the cockpit  12  and another user (e.g., a co-pilot) may be present at the right side of the cockpit  12  in a seat  16 . A cockpit instrument panel  18  having various instruments  20  and multiple multifunction flight displays  22  may be located in front of the pilot and co-pilot and may provide the flight crew with information to aid in flying the aircraft  10 . 
     The flight displays  22  may include either primary flight displays or multi-function displays and may display a wide range of aircraft, flight, navigation, and other information used in the operation and control of the aircraft  10 . The flight displays  22  may be capable of displaying color graphics and text to a user. The flight displays  22  may be laid out in any manner including having fewer or more displays and need not be coplanar or the same size. A touch screen display or touch screen surface  24  may be included in the flight display  22  and may be used by one or more flight crew members, including the pilot and co-pilot, to interact with the systems of the aircraft  10 . It is contemplated that one or more cursor control devices  26  and one or more multifunction keyboards  28  may be included in the cockpit  12  and may also be used by one or more flight crew members to interact with the systems of the aircraft  10 . 
     A controller  30  may be operably coupled to components of the aircraft  10  including the flight displays  22 , touch screen surface  24 , cursor control devices  26 , and keyboards  28 . The controller  30  may also be connected with other controllers (not shown) of the aircraft  10 . The controller  30  may include memory and processing units, which may be running any suitable programs to implement a graphical user interface (GUI) and operating system. These programs typically include a device driver that allows the user to perform functions on the touch screen surface  24  such as selecting options, inputting commands and other data, selecting and opening files, and moving icons through the touch screen surface  24 . 
     The controller  30  may include a computer searchable database of information (not shown) or may be operably coupled to a database of information. For example, such a database may be stored on an alternative computer or controller. It will be understood that the database may be any suitable database, including a single database having multiple sets of data, multiple discrete databases linked together, or even a simple table of data. A pilot may have the ability to upload preferential cockpit configuration data upon system startup such as through a flight guidance or flight mode select control panel that may be displayed on the touch screen surface  24 , the cursor control devices  26 , and/or the multifunction keyboards  28 . The default cockpit configuration may take into consideration regulatory requirements e.g., FAA, airline company or aircraft operator, operations manual or specifications requirements and also pilot preference for cockpit configuration of thrust modes, instrument and display layouts, company, airfield, and regulatory recommended, best practices and pilot optioned best practices for start-up, taxi, takeoff, departure procedures, climb, cruise, descent, arrival procedures, approach procedure selection, landing, reverse thrust usage, and taxi techniques. The database may also include runway data, aircraft performance data, engine performance data, runway surface conditions, current outside weather conditions, historical takeoff performance, and current fuel prices. It is contemplated that such a database may be located off the aircraft  10  at a location such as airline or flight operations department control (not shown) or another location and that the controller  30  may be operably coupled to a wireless network (not shown) over which the database information may be provided to the controller  30 . This database may include pilot preferential data inputted via electronic means i.e. flash memory, internet, WiFi, LAN, SatComm or other electronic delivery means. 
     During operation, the controller  30  may utilize inputs from the pilot, the database, and/or information from airline control or flight operations department to present a graphic depiction of the predicted takeoff performance of the aircraft  10 . The pilot may be able to use the input device to adjust the derated setting of the thrust of the engines of the aircraft  10  and the controller  30  may update the flight display  22  based on the selection. Once the pilot has determined that a suitable selection has been made, the pilot may use the input device to accept and activate the takeoff parameters. 
     Referring now to  FIG. 2 , a first embodiment showing the illustration of several derated takeoff settings  34  and  36  for the aircraft  10  is shown. The derated takeoff setting  34  correlates to a setting having 80% of the full thrust available and the derated takeoff setting  36  correlates to a setting having 70% of the full thrust available. It is contemplated that the entire climb profile, including multiple segments thereof may be illustrated. 
     A runway representation  38  of the runway on which the aircraft  10  is to takeoff is displayed on the flight display  22 . It will be understood that the runway representation  38  may be graphically illustrated in a variety of ways and that various aspects of the runway may be illustrated on the flight display  22  to better aid the pilot in making decisions with respect to the derated takeoff thrust setting. For example, the runway representation  38  may be made  3 D, may illustrate various characteristics of the runway including the centerline and slope. By way of further example, the runway representation  38  includes an undulation indicator  40  where a dip is located in the runway. 
     Takeoff indicia for the derated takeoff settings  34  and  36  are also displayed in reference to the runway representation  38 . The takeoff indicia may represent a location along the runway where the aircraft  10  is airborne for a corresponding thrust setting, which is less than a full thrust setting. For example, a first takeoff indicia  42  represents where the aircraft  10  will be airborne for the derated takeoff setting  34  and a second takeoff indicia  44  represent where the aircraft  10  will be airborne for the derated takeoff setting  36 . 
     The illustration may also give an indication of where the aircraft  10  may takeoff under a full thrust setting to give the pilot a basis to make a comparison. For example, a full thrust setting  46  has been illustrated with takeoff indicia  48 . While the flight display  22  has been illustrated as displaying multiple takeoff indicia, it will be understood that only a single derated takeoff setting and its corresponding takeoff indicia may be shown at a time either with or without the full thrust setting illustrated for comparison. Further, the takeoff indicia may take many forms to illustrate the point where the aircraft  10  will be airborne. For example, the takeoff indicia may include but is not limited to marking at least the point of takeoff of the aircraft  10  or may include a bar or zone representing the takeoff distance ending at the takeoff point. 
     The takeoff indicia  42  and  44  for each of the illustrated derated takeoff settings  34  and  36  may represent a variety of things including the location at which all wheels of the aircraft  10  are predicted to be out of contact with the runway. The takeoff indicia  42  and  44  may also represent the location at which the aircraft  10  will clear any known obstacles, such as the obstacle  50 , beyond the runway at the derated takeoff setting. Such obstacle information may be available from a terrain database. The takeoff indicia  42  and  44  may also illustrate a predicted distance needed for the aircraft  10  to takeoff at the derated takeoff setting. The takeoff indicia  42  and  44  may illustrate any combination of such takeoff information on the flight display  22 . The illustration may also give an indication of the effect of a loss of an engine at some point during takeoff and it may be indicated that the aircraft may continue to climb at the derated thrust after that point on one engine. The illustration may also show required changes to the thrust when an engine is lost and it may be shown whether such changes may be implemented automatically by the controller  30 . Further, the illustration may also give some indication of any procedural thrust setting changes along the profile (e.g., normal power reduction, or power reduction required by noise abatement). Further still, the illustration may also give some indication of the effects of inoperative equipment such as inoperative anti-skid or the use of emergency braking. 
     It will be understood that the location of the takeoff indicia  42  and  44  may be predicted based on at least one of: runway data, aircraft performance, engine performance, runway surface conditions, and current outside weather conditions. That is the controller  30 , or a computer located off the aircraft  10 , may determine the location of takeoff of the aircraft  10  based on a variety of information available to it. Runway data may include information related to the structure of the runway including its shape, location, length, non-standard climb gradients, and slope. Such information may come from a runway database. Aircraft performance may include aerodynamics of the aircraft  10  and engine performance may include precision performance characteristics of the engines on the aircraft  10 . Runway surface conditions may include information related to the type of material forming the runway, as well as weather the runway is currently slick or icy. Current outside weather conditions may include, among other things, air temperature, wind direction, and wind speed. The location of the takeoff indicia  42  and  44  may also take into consideration the weight and balance of the aircraft itself. 
     A takeoff trajectory for each of the illustrated derated takeoff settings may also be displayed. For example, a first takeoff trajectory  52  for the derated takeoff setting  34  and a second takeoff trajectory  54  for the derated takeoff setting  36  are shown. The illustration of the takeoff trajectories  52  and  54  are with reference to the runway representation and may be particularly useful where there are known obstacles such as the obstacle  50 . 
     Cost indicia  56  corresponding to the takeoffs at the derated takeoff settings may also be displayed. Such indicia may illustrate a cost savings of the takeoff at the derated takeoff settings relative to a takeoff at the full thrust setting. For exemplary purposes, the cost indicia  56  illustrate the cost savings for each derated takeoff setting in dollars. The cost indicia  56  may be illustrated in other manners both graphically and in terms of what information is provided. For example, the cost indicia  56  could alternatively indicate the pounds of fuel that will be saved at the derated takeoff setting or give information related to some pilot incentive related to the derated takeoff setting. 
     Braking indicia  58  with reference to the runway representation  38  may be included and may illustrate the location beyond takeoff indicia  42  at which the aircraft  10  is predicted to stop after aborting the takeoff. It is contemplated that the braking indicia  58  may illustrate at least the location at which the aircraft  10  will stop on the runway under full braking after aborting the takeoff at the location indicated by the takeoff indicia  42 . Similarly, braking indicia  60  is shown for the corresponding takeoff indicia  44 . 
       FIG. 3  illustrates a second embodiment of an exemplary flight display  22  illustrating a derated takeoff setting  134 . The second embodiment is similar to the first embodiment; therefore, like parts will be identified with like numerals increased by 100, with it being understood that the description of the like parts of the first embodiment applies to the second embodiment, unless otherwise noted. The derated takeoff setting may have been selected by the pilot and illustrated on the flight display  22  to give the pilot information regarding the derated thrust. The controller  30  may update the flight display  22  with runway information, savings information, and performance information. Like the earlier embodiment a runway representation  138 , takeoff indicia  142 , takeoff trajectory  152 , cost indicia  156 , and braking indicia  158  have been included for the derated takeoff setting  134 . Unlike the first embodiment the takeoff indicia  142  has been illustrated as zone, which represents the takeoff distance ending at the takeoff point. Further, the takeoff trajectory  152  has been shown as having different characteristics. 
     Unlike the first embodiment, historical takeoff indicia  170  has also been included and illustrates the location along the runway for prior aircraft takeoffs at the same derated takeoff setting. The prior aircraft takeoff information considered in determining the historical takeoff indicia may be for the current aircraft  10  that is being flown, for the same or similar type of aircraft as the current aircraft  10  being flown, or a combination of the two. The historical takeoff indicia may illustrate a variety of historical information regarding the prior aircraft takeoffs. For example, the historical takeoff indicia  170  may include an average of all of the takeoffs, a running average, a sliding average, etc. Such information may allow the pilot to see how previous flights performed at such a derated takeoff setting. It is contemplated that upon takeoff, the aircraft&#39;s takeoff performance data may be stored to a data repository to be accessible by future flights in determining the historical takeoff indicia  170 . It is contemplated that the historical database may pick out trends of the historical data and that the historical takeoff indicia  170  may shift or grow as more information is available. Historical indicia may be included for any of the other indicia given on the flight display  22  including for the braking indicia and may be determined by the use of FDM, FOQA or other historical database tracking system. 
     Further, safety indicia  172  has also been included for the derated takeoff setting  134 . Such safety indicia  172  may indicate a safety margin for a takeoff at the derated takeoff setting  134 . The safety margin indicated by the safety indicia  172  may be determined by the airline operator and may include a set amount of length at the end of the runway, such as 2,000 feet, that the airline operator wishes to maintain as a safety barrier for safety issues such as malfunctioning or sub-functioning brakes. Further, it is contemplated that the pilot may include a custom safety margin such as the airline control margin plus an additional percentage or factor due to runway conditions, equipment malfunctions or regulatory requirements. 
     It is also contemplated that error indicia  174  illustrating the potential error in other various information may be displayed on the flight display  22 . For example, error indicia  174  has been given with respect to the braking indicia  158 . In the exemplary instance the error indicia  174  indicates the error in the calculation of the braking indicia  158 . It is contemplated that if the error indicia  174  indicates that the braking indicia  158  overlaps with the safety indicia  172  then the pilot may be instructed to select a different derated takeoff setting or an indication of such an overlap may be given on the flight display  22 . Error indicia may be included for any of the indicia given on the flight display  22  and may be determined in by the use of FDM, FOQA or other historical database tracking system. 
     It is contemplated that the controller  30  may be capable of autocorrecting the pilot selection of the derated takeoff setting if the error indicia  174  or the historical takeoff indicia  170  indicate that braking of the aircraft  10  may not occur before the safety margin. The auto-correction of the takeoff derated selection utilizes historical FOQA or FDM type data to determine error indicia with automatic resetting of takeoff power done by comparing data gathered to airline, company or regulatory requirements for takeoff power selection. 
     It is also contemplated that additional information may be displayed on the flight display  22  with respect to the derated takeoff setting  134 . For example, if a pilot derates the thrust of the engines by 20%, resulting in over 2000 ft. of runway remaining when they actually takeoff, the pilot will be presented with a list of runways that this accurately correlates with when taking off at full thrust. It is assumed that such a correlation will provide the pilot with reassurance that performing the 20% derated thrust is physically identical to operating at full thrust on another runway and the pilot will be more likely to operate under the derated thrust accordingly. In this manner it may be conveyed to the pilot that while the aircraft  10  may run a little longer on the given runway as it is not as difficult of a runway to takeoff on. Further, it will be understood that any portion of the described indicia in the embodiments above may be used on the flight display  22  and that any of the functionality of the two embodiments described above may be combined with each other in any manner. It is also contemplated that indicia may be included to show the effects of the takeoff on the long-term reliability of the aircraft; for example, indicia to illustrate the effects of the thrust setting on engine wear and tear may be included. 
     The above described embodiments provide a variety of benefits including that the pilot may make a more accurate assessment of the results of a derated takeoff setting. The technical effect of the embodiments of the invention being that the pilot is presented with a graphical representation of the predicted takeoff performance when performed with derated thrust of the engines and may aid in alleviating pilot concerns regarding runway length. This may subsequently result in an increase in the likelihood of the pilot performing the derated takeoff maneuver. The selection of the derated takeoff setting saves a significant amount of fuel and extends the life of the engines on the aircraft by reducing stress on life-limited components, greatly reducing the operating costs of the airline and other flight operators. As fuel represents the single greatest cost to such operators a reduction would provide an immediate benefit. Further, the crew of the aircraft may be provided with additional helpful information such as predicted remaining runway or stopping time for the aircraft which may result in improved operation of the aircraft. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.