Abstract:
The device for checking speed intended for an aircraft ready to land on deck on a moving vehicle, the aircraft having a current vertical speed, called the first speed, and a threshold value of vertical downward speed relating to the vertical speed of the moving vehicle, called the “low threshold”, the ship having an absolute vertical speed, called the second speed, comprises a display and means for receiving data originating from the aircraft, notably its vertical absolute speed. The device includes a calculator making it possible to generate on the display a graduated speed gauge including a fixed cursor indicating the first vertical speed and a second moving cursor indicating the speed of the ship, a third moving cursor indicating the low threshold, the graduation being centred around the value of the first vertical speed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to foreign French patent application No. FR 0905264, filed on Nov. 3, 2009, the disclosure of which is incorporated by reference in its entirety. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to the field of devices for generating data displayed in a display intended for controlling and monitoring the manoeuvres of an aircraft when landing. More particularly, the devices of the invention relate to the monitoring and control of pilotless aircraft manoeuvring in phases of landing on a deck of a moving platform such as a ship. 
       BACKGROUND 
       [0003]    Generally, pilotless aircraft control and monitoring missions may be of various kinds. Notably, they may relate to the monitoring of the takeoff or landing phases or else the monitoring of the proper following of the flight plan during the navigation of such an aircraft. 
         [0004]    An operator usually has a display system at his disposal, allowing him to monitor the behaviour of the aircraft and to take decisions, for example a mission cancellation decision, if need be. 
         [0005]    In the course of the takeoff or landing phases, the operator must be reactive. In the event of incidents, the mission must be rapidly interrupted so as to provide for the safety, firstly, of the onboard personnel in proximity to the landing zone and secondly, of the apparatus itself. 
         [0006]    When the landing or takeoff zone is moving, a drawback resides in the difficulty of controlling the manoeuvres of a remotely controlled aircraft while guaranteeing maximum safety in the vicinity. 
         [0007]    Typically, when the landing takes place on a ship, the swell, the wind and the relative vertical motions of the aircraft and of the ship may comprise risks in the execution of the manoeuvres. 
         [0008]    The vertical speed of the aircraft, during a deck landing for example, must always be compared and measured in relation to the vertical speed of the ship. 
         [0009]    A current solution consists in displaying the two items of information previously introduced: the absolute vertical speed of the aircraft and the absolute vertical speed of the ship in two distinct indicators. 
         [0010]    An embodiment of the prior art proposes two graduated displays which represent vertical speed gauges, respectively for an aircraft and for a ship. 
         [0011]      FIG. 1  represents such gauges which allow an operator to monitor the landing of an aircraft on the deck of the ship. 
         [0012]    A first gauge makes it possible to indicate the vertical speed V 1  of the aircraft during a deck-landing phase or deck-landing preparation phase. A second gauge makes it possible to indicate the vertical speed V 2  of the ship. 
         [0013]    The speeds of the aircraft and of the ship are represented in two indicators, formed by the gauges, independently of one another. This solution allows an operator to follow the variations of the various speeds. However this solution possesses drawbacks. 
         [0014]    First of all, the items of information are represented in different indicators, they are therefore difficult to monitor simultaneously. 
         [0015]    Thereafter this solution proposes only independent monitoring of the two speeds. It does not allow the operator to appraise the impacts of the dynamics of the ship on the aircraft, especially at the time of the deck-landing when the aircraft is approaching the deck where the least error can constitute an imminent danger. The two indicators become a drawback in respect of monitoring since the operator&#39;s attention must be focused on two gauges. 
         [0016]    Indeed, during the takeoff and deck-landing phases, the aircraft&#39;s movements do not take place within a fixed reference frame but within a moving reference frame. The combination of the two speeds therefore influences the decision that must be taken by the operator. This dependency is not currently represented. This may therefore result in the operator taking a decision too late. 
       SUMMARY OF THE INVENTION 
       [0017]    The invention alleviates the aforementioned drawbacks. 
         [0018]    The invention makes it possible to ensure the monitoring of the deck-landing or landing manoeuvres when items of information originate from two moving systems such as an aircraft and a ship whose dynamics are different. 
         [0019]    The invention makes it possible to generate indicators allowing representation of the absolute vertical speeds of the aircraft and of the ship ensuring a unique monitoring point. The invention makes it possible to monitor a criterion generated so as to rapidly and flawlessly detect a speed value that could threaten the mission. 
         [0020]    Advantageously, the device for checking speed intended for an aircraft ready to land on deck on a moving vehicle, the aircraft having a current vertical speed, called the first speed, the moving vehicle having a vertical speed, called the second speed, a first setpoint being defined, the said setpoint corresponding to the desired limit of vertical downward speed of the aircraft in relation to the vertical speed of the moving vehicle, comprises a display and means for receiving data originating from the aircraft, notably its vertical absolute speed. 
         [0021]    Advantageously, the device comprises a calculator making it possible to generate on the display a graduated speed gauge comprising a first fixed cursor indicating the value of the first speed and a second moving cursor indicating the value of the second speed, a third moving cursor indicating the first setpoint, the graduation being centred around the value of the first vertical speed. 
         [0022]    Advantageously, a first zone lying between the second and the third cursor comprises a first noteworthy graphical element allowing an operator to check that the first speed is not situated below the said zone. 
         [0023]    Advantageously, the first graphical element is a colour. 
         [0024]    Advantageously, a second zone situated below the third cursor comprises a second noteworthy graphical element. 
         [0025]    Advantageously, the second graphical element is a different colour from the first graphical element. 
         [0026]    Advantageously, a predefined high threshold is generated in the form of a fourth cursor in the gauge corresponding to a maximum limit speed of the aircraft. 
         [0027]    Advantageously, a predefined low threshold is generated in the form of a fifth cursor in the gauge corresponding to a minimum limit speed of the aircraft. 
         [0028]    Advantageously, a zone is situated beyond the fourth or the fifth cursor and it comprises a third noteworthy graphical element indicating a danger zone. 
         [0029]    Advantageously, the third graphical element is a colour. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    Other characteristics and advantages of the invention will become apparent with the aid of the description which follows, given in conjunction with the appended drawings which represent: 
           [0031]      FIG. 1 : two speed indicators of the prior art; 
           [0032]      FIG. 2 : an indicator of the relative speed of the invention between an aircraft and a ship in a first typical case; 
           [0033]      FIG. 3A ,  3 B,  3 C,  3 D: four configurations of an indicator of the relative speed of the invention between an aircraft and a ship in a second typical case; 
           [0034]      FIG. 4A ,  4 B,  4 C,  4 D: four configurations of an indicator of the relative speed of the invention between an aircraft and a ship in a third typical case. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]      FIG. 2  represents a configuration in which the invention applies. It involves a typical case where an aircraft  10  is in position ready to land on the deck of a ship  11 . The control tower  14  receives information originating from the aircraft  10 , notably as to its speed V 1 . The operator must be able to check throughout the descent of the aircraft  10  that its vertical speed V 1  with respect to the ship&#39;s vertical speed V 2  caused notably by the swell  13  remains within a certain limit. 
         [0036]    The discrepancy between the vertical speed of the aircraft and that of the ship must adhere to a certain limit beyond which the risks of a violent landing may cause damage or be detrimental to the safety of the ship&#39;s crew. 
         [0037]    The invention makes it possible to check in one and the same indicator that the relative speed of V 1  with respect to the speed V 2  remains within a certain predefined limit. 
         [0038]      FIG. 3  represents an indicator  30  representing a graduated gauge whose graduations represent speed units. The invention makes it possible to generate on one and the same indicator  30  the values of the two vertical speeds, respectively of the ship and of the aircraft, so as to provide for the checking of the vertical relative speed of the aircraft with respect to that of the ship. 
         [0039]    The vertical speed of the aircraft is represented by the cursor  32 , the absolute vertical speed of the ship is represented by the cursor  22 . 
         [0040]    The cursor  24  represents a first predefined setpoint representing the desired limit of the vertical speed of the aircraft in relation to the vertical speed of the ship. This entails a cursor representing a relative datum. 
         [0041]    It is important that the aircraft does not possess too great a descent speed while the ship has an upward speed caused by the swell. A risk of violent landing could then arise. 
         [0042]    An advantage of the invention is that the cursor representing the vertical speed of the aircraft is fixed in the indicator  30 . Depending on the relative speed of the aircraft with respect to that of the ship, the zone  31  may then move towards the zone  21  or towards the zone  23 . 
         [0043]    In a particular embodiment, the indicator  30  can represent a delimitation such as the cursor  24  and below which a danger zone is visually noteworthy. 
         [0044]      FIG. 3B  illustrates this embodiment. The zone  23 ′ which is situated below the cursor  24  can comprise a colour code or a representation which allows the operator to rapidly pinpoint the danger zone. 
         [0045]    An advantage for the operator is to be able to have at his disposal a single indicator  30 , thereby making it possible to be reactive regarding the changes in the relative speed. The invention therefore allows an operator to detect rapidly and without error an excessive value of the relative vertical speed of the aircraft  10  in the moving reference frame tied to the ship  11 . 
         [0046]      FIGS. 3A and 3B  make it possible to represent the indicator  30  making it possible to read the absolute vertical speed of the aircraft by way of the cursor  32 . In one embodiment, a symbol  20  can comprise a triangle pointing at the ordinate corresponding to the vertical speed of the aircraft. This triangle is therefore fixed in the indicator  30 . 
         [0047]    An advantage of the invention is that the set of graduations represent a moving scale, which scrolls according to the speed of the aircraft. 
         [0048]    In this case, inside the indicator  30  is a moving scale whose graduations are the possible speed values. This scale translates vertically. The value of the vertical speed of the aircraft is indicated by the symbol  20  which is aligned with the cursor  32 . 
         [0049]    In the example of  FIG. 3A , the absolute vertical speed of the aircraft is 1 m/s downwards, the vertical speed of the ship is 0 m/s and the first setpoint is 2 m/s downwards. 
         [0050]      FIG. 3C  represents the indicator  30  while the aircraft has a vertical speed of 1 m/s downwards. On the other hand, the ship has a vertical speed of between 1 and 2 m/s upwards, its speed being represented by the cursor  22 . 
         [0051]    It is realized straight away by reading the information of the indicator  30  that the cursor  32  representing the vertical speed of the aircraft is in the danger zone  23 . 
         [0052]    The operator can then undertake corrective measures very rapidly as soon as he observes such a situation. 
         [0053]      FIG. 3D  represents the indicator  30  while the aircraft has a vertical speed of 1 m/s downwards. On the other hand, the ship has a vertical speed of between 2 and 3 m/s downwards, its speed being represented by the cursor  22 . 
         [0054]    It is realized straight away that the cursor  32  representing the vertical speed of the aircraft is beyond the danger zone  23 , the operator can for example undertake manipulations aimed at restoring the position of the cursor  20  below the vertical speed of the ship so as to land the aircraft on the deck of the ship. 
         [0055]    In the embodiments of  FIGS. 3A ,  3 B,  3 C and  3 D, the discrepancy is constant between the absolute speed of the ship represented by the cursor  22  and the first setpoint represented by the cursor  24 . In the examples of  FIGS. 3A ,  3 B,  3 C and  3 D, this discrepancy is 2 m/s. 
         [0056]    The invention makes it possible to configure this discrepancy as a function of the missions and contexts of flight. This discrepancy represents, in  FIGS. 3A ,  3 B, C and  3 D, a zone  31  corresponding to an authorized range of speeds for the aircraft while the zone  23 ,  23 ′ represents an a priori prohibited range of speeds of the aircraft. 
         [0057]    When the aircraft has a speed beyond the cursor  22 , it is not in a danger configuration. On the other hand, it is not in a commenced phase of the landing. This range can correspond to a landing preparation phase. 
         [0058]    This representation makes it possible to present in a permanent manner the vertical speed of the aircraft  32 , centred and fixed in the indicator  30 . The speed ranges representing a danger or the authorized speed ranges shift vertically in the indicator  30 . The vertical shift of the graduation and therefore of the speed ranges previously mentioned is dependent on the absolute speeds of the ship and of the aircraft. 
         [0059]    The invention makes it possible to represent in an intuitive manner the entry of the absolute vertical speed of the aircraft into the non-authorized speed range. For this purpose, it suffices that the aircraft&#39;s absolute speed cursor lies in an unauthorized zone whose colour code may be noteworthy. An alarm is then raised. 
         [0060]    The various configurations represented in  FIGS. 3A ,  3 B,  3 C and  3 D are summarized. 
         [0061]    The configuration of  FIG. 3A  is:
       Absolute vertical speed of the aircraft: 1 m/s downwards   Absolute vertical speed of the ship: 0 m/s   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: 2 m/s downwards   No speed alarm is triggered       
 
         [0066]    The configuration of  FIG. 3B  is:
       Absolute vertical speed of the aircraft: 1 m/s downwards   Absolute vertical speed of the ship: 0 m/s   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: 2 m/s downwards   No speed alarm is triggered       
 
         [0071]    The configuration of  FIG. 3C  is:
       Absolute vertical speed of the aircraft: 1 m/s downwards   Absolute vertical speed of the ship: 1.7 m/s upwards   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: 0.3 m/s downwards   A speed alarm is triggered       
 
         [0076]    The configuration of  FIG. 3D  is:
       Absolute vertical speed of the aircraft: 1 m/s downwards   Absolute vertical speed of the ship: 2.3 m/s downwards   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: 4.3 m/s downwards   No speed alarm is triggered       
 
         [0081]    Just like for numerous flight parameters, the vertical speed of the aircraft is limited to a domain of predefined acceptable speeds. 
         [0082]      FIG. 4A  represents a typical case where the speed of the aircraft is close to the acceptable maximum limit represented by a cursor  41 . 
         [0083]    The moving cursor  41  symbolizes the aircraft&#39;s maximum limit of absolute vertical speed desired. Beyond the cursor  41 , the speed range defines a zone  42  in which the aircraft incurs a risk. 
         [0084]      FIG. 4B  represents a typical case where the speed of the aircraft is close to the acceptable minimum limit represented by a cursor  43 . 
         [0085]    The moving cursor  43  symbolizes the aircraft&#39;s minimum limit of absolute vertical speed desired. Below the cursor  43 , the speed range defines a zone  44  in which the aircraft incurs a risk. 
         [0086]    The dynamics of the reference frame tied to the ship within which the aircraft is travelling may be represented by the indicator  30 . The cursors  41  and  43  indicate the thresholds of acceptable speed of the absolute speed of the aircraft upwards and downwards referred to the moving reference frame tied to the ship. 
         [0087]    In the example of  FIG. 4A , the aircraft&#39;s acceptable upward vertical speed threshold indicates the speed of 15 m/s upwards. And in the example of  FIG. 4B , the aircraft&#39;s acceptable downward vertical speed threshold indicates the speed of 15 m/s downwards. 
         [0088]      FIGS. 3A ,  3 B,  3 C and  3 D do not represent the maximum and minimum limit values since the aircraft&#39;s absolute speed is not close to these limits. 
         [0089]    The generation of these thresholds  41  and  43  in the indicator  30  may be combined with an alarm device. The alarm device may be integrated into the indicator by way of a colour code making it possible to differentiate the acceptable zone from the vertical speed zones which are unacceptable for the aircraft. 
         [0090]    At any instant the speed cursor must be inside the zone defined by the two thresholds  41  and  43  so as to remain in the safe flight domain. In the event of departure from the safety zone, an alarm is raised. Advantageously, the zones  42  and  44  have an inherent colour representing a danger zone so as to make it easier for an operator to read. 
         [0091]      FIGS. 4C and 4D  represent two configurations where the cursor representing the vertical speed of the aircraft is in one prohibited zone  42 ,  44 . In these typical cases, an alarm is raised indicating the imminence of a danger. 
         [0092]    The configuration of  FIG. 4A  is:
       Absolute vertical speed of the aircraft: 14 m/s upwards   Limit vertical speed of the aircraft upwards: 15 m/s   Absolute vertical speed of the ship: not represented   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: not represented   No speed alarm is triggered       
 
         [0098]    The configuration of  FIG. 4B  is:
       Absolute vertical speed of the aircraft: 14 m/s downwards   Limit vertical speed of the aircraft downwards: 15 m/s   Absolute vertical speed of the ship: not represented   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: not represented   No speed alarm is triggered       
 
         [0104]    The configuration of  FIG. 4C  is:
       Absolute vertical speed of the aircraft: 16 m/s upwards   Limit vertical speed of the aircraft upwards: 15 m/s   Absolute vertical speed of the ship: not represented   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: not represented   A speed alarm is triggered       
 
         [0110]    The configuration of  FIG. 4D  is:
       Absolute vertical speed of the aircraft: 16 m/s downwards   Limit vertical speed of the aircraft downwards: 15 m/s   Absolute vertical speed of the ship: not represented   The limit acceptable relative vertical speed of the aircraft in the ship moving reference frame: not represented   A speed alarm is triggered       
 
         [0116]    The invention comprises numerous advantages. Notably the representation of the vertical speeds when landing an aircraft on the deck of a ship in motion may be controlled on the basis of a unique indicator. The indicator comprises various cursors generated and arranged so as to make it easier to analyze and to read sensitive data. 
         [0117]    Moreover the invention makes it possible to generate an indicator correlating first speed information and danger zones. 
         [0118]    Finally the invention makes it possible to generate alarms when certain limit speeds are crossed.