Contact detecting system and method for air refueling tanker equipped with air refueling boom system

Abstract

A contact detecting system for an air refueling tanker equipped with an air refueling boom, the system comprising a boom refueling nozzle comprising a valve to allow the exit of fuel, a latch to engage the refueling nozzle, a first contact detecting mechanism configured to transmit a signal when the refueling nozzle is in a contact position, a second contact detecting mechanism configured to detect the position of the latch and to transmit a signal when the latch is latched, and a third contact detecting mechanism configured to detect the position of the valve and to transmit a signal when the valve is open. The system further comprises a computing device configured to receive the signals from the first, second and third contact detecting mechanisms and to provide an output signal of the contact status of the refueling nozzle.

Claims

1. A contact detecting system for an air refueling tanker equipped with an air refueling boom configured to be introduced into a receptacle of a receiver aircraft, the system comprising a boom refueling nozzle comprising: a valve configured to allow the exit of fuel to the receiver aircraft, a latch configured to engage the refueling nozzle to the receptacle of the receiver aircraft, a first contact detecting mechanism configured to transmit a positive signal when the refueling nozzle achieves a contact position in the receptacle of the receiver aircraft and a negative signal when the refueling nozzle does not achieve the contact position, a second contact detecting mechanism configured to detect a status of the latch and configured to transmit a positive signal when the latch is in a latched status and negative when the latch is in a not latched status, a third contact detecting mechanism configured to detect a position of the valve and configured to transmit a positive signal when the valve is in an open state and negative when the valve is in a closed state, wherein the system further comprises a computing device which receives the signals from each of the first, second and third contact detecting mechanisms and analyzes the signals in combination and provides an output signal of the contact status of the refueling nozzle to the tanker aircraft.

2. The contact detecting system according to claim 1, wherein the computing device is configured to generate an output signal to the tanker aircraft for aborting the refueling operation when the received signal from the third contact detecting mechanism is negative and at least the received signal from the first or the second contact detecting mechanism is also negative.

3. The contact detecting system according to claim 1, further comprising a recording device for recording the analyzed data.

4. The contact detecting system according to claim 1, wherein the computing device is configured to provide an output signal triggering a maintenance signal when the received signal from the third contact detecting mechanism is positive and at least the received signal from the second or the first detecting mechanism is negative.

5. The contact detecting system according to claim 1, wherein the computing device is configured to provide an output signal triggering a maintenance signal when the received signal from the third contact detecting mechanism is negative and the received signal from the second contact detecting mechanism and the received signal from the second and the first contact detecting mechanisms are positive.

6. The contact detecting system, according to claim 1, wherein the first contact detecting mechanism comprises an induced coil configured to transmit the positive signal when the refueling nozzle achieves a contact position.

7. The contact detecting system, according to claim 1, further comprising two latches and two contact detecting mechanisms each for latch, the computing device being configured for firstly analyzing the signals coming from each latch in the following way: if both signals from the latches are positive, the latches status will be positive (latched), if one or more of the signals from the latches are negative the latches status will be negative.

8. The contact detecting system, according to claim 1, wherein the second contact detecting mechanism comprises: two plaques isolated between each other and isolated from the nozzle, a third plaque located apart from the two plaques and isolated from the nozzle, which third plaque is configured to not be in contact with the two plaques if the latch is not in a latched state and for being in contact with the two plaques if the latch is in a latched state, a first and a second cable connecting respectively each two plaques with the computing device, the two plaques, the third plaque, the first and second cable and the computing device being configured such that when the plaques are in contact there is continuity between the computing device, the cable connected to the first plaque and the third plaque, the second plaque, the cable connected to the second plaque and finally to the computing device.

9. The contact detecting system, according to claim 1, wherein the third contact detecting mechanism comprises a load cell configured to measure a force exerted by a spring configured to be compressed when the valve is in an open position.

10. A refueling tanker aircraft comprising a contact detecting system for the air refueling tanker equipped with an air refueling boom configured to be introduced into a receptacle of a receiver aircraft, the contact detecting system comprising a boom refueling nozzle comprising: a valve configured to allow the exit of fuel to the receiver aircraft, a latch configured to engage the refueling nozzle to the receptacle of the receiver aircraft, a first contact detecting mechanism configured to transmit a positive signal when the refueling nozzle achieves a contact position in the receptacle of the receiver aircraft and a negative signal when the refueling nozzle does not achieve the contact position, a second contact detecting mechanism configured to detect a position of the latch and configured to transmit a positive signal when the latch is in a latched status and negative when the latch is in a not latched status, a third contact detecting mechanism configured to detect a position of the valve and configured to transmit a positive signal when the valve is in an open state and negative when the valve is in a closed state, wherein the system further comprises a computing device which receives the signals from each of the first, second and third contact detecting mechanisms and analyzes the signals in combination and provides an output signal of the contact status of the refueling nozzle to the tanker aircraft.

11. A contact detecting method for an air refueling tanker equipped with an air refueling boom capable of being introduced into a receptacle of a receiver aircraft, wherein a boom refueling nozzle comprises a valve configured to allow an exit of fuel to the receiver aircraft, a latch configured to engage to the receptacle of the receiver aircraft, a first contact detecting mechanism configured to transmit a positive signal when the refueling nozzle achieves a contact position in the receptacle of the receiver aircraft and a negative signal when the refueling nozzle does not achieve the contact position, a second contact detecting mechanism configured to detect a position of the latch and configured to transmit a positive signal when the latch is in a latched state and a negative signal when the latch is not in a latched state, a third contact detecting mechanism configured to detect the position of the valve and configured to transmit a positive signal when the valve is in an open state and a negative signal when the valve is in a closed state, the contact detecting method comprises the following steps: reading and transmitting a signal from the first contact detecting mechanism when the refueling nozzle achieves a contact position in the receptacle of the receiver aircraft, reading and transmitting a signal from the second contact detecting mechanism detecting the position of the latch, reading and transmitting a signal from the third contact detecting mechanism detecting the position of the valve, receiving the signals by a computing device, analyzing the signals by the computing device in combination, and providing an output signal from the computing device to the tanker aircraft of the contact status of the nozzle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. The drawings form an integral part of the description and illustrate preferred embodiments of the invention. The drawings comprise the following figures.

(2) FIG. 1 shows a block diagram according to an embodiment of the invention.

(3) FIG. 2 shows a perspective view of a boom refueling nozzle according to an embodiment of the invention.

(4) FIGS. 3A and 3B show a perspective view of an embodiment of a contact detection mechanism located in a latch of the nozzle.

(5) FIG. 4 shows the embodiment of the contact detection mechanism located in a latch of the nozzle in a no contact position.

(6) FIG. 5 shows the embodiment of the contact detection mechanism in a latch of the nozzle of FIG. 4 in a contact position.

(7) FIG. 6 shows an embodiment of the contact detection mechanism located in the valve of the nozzle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) FIG. 1 represents a block diagram of an embodiment of the invention. The nozzle (1) is equipped with the three contact detection mechanisms (3, 5, 14) that are configured to transmit first, second and third signals (20, 25, 26, 30) respectively to the computing device (50). The computing device (50) is configured to compute the combined information and to provide an output signal (60) comprising the connect status of the nozzle (1). The computed status will be either contact or no contact.

(9) The computing device (50) of the embodiment, digital or analog computer, is remotely located from the boom nozzle (1), based on wiring logic, receiving the signals (20, 25, 26, 30) from the contact detection mechanisms (3, 5, 14) implemented into the nozzle (1). The computing device (50) will receive and process these signals (20, 25, 26, 30) in combination, and will provide an output computed signal (60) of Nozzle Contact Status to the rest of tanker aircraft systems and hence to the boom operator. Therefore, real time information is provided to the tanker aircraft or to the boom operator about the status of the system.

(10) As shown in FIG. 2, the end of the tube or nozzle (1) comprises some latches (5). On the other side, the receptacle of the receiver aircraft comprises some triggers (not represented), normally activated by hydraulic mechanisms, the triggers having the purposes of attaching and blocking the nozzle (1) of the telescoping tube by means of the clamps on the tube. Once the nozzle (1) makes contact and connects to the receptacle, the boomer may commence the transfer of fuel from the tanker aircraft to the receiver aircraft in a safe manner

(11) One embodiment of the invention comprises a system comprising a boom refueling nozzle (1) provided with:

(12) An induced coil (3) which transmits a pulse signal (20) when the nozzle (1) achieves the contact position.

(13) One or more contact detection mechanisms implemented in the latches (5) of the nozzle (1). In the depicted embodiment, one contact detection mechanism will be implemented on each of the two latches (5).

(14) FIGS. 3A, 3B, 4 and 5 disclose an embodiment of the contact detection mechanism for the latches (5) that will detect the contact of a roller (12) of the receptacle onto the latch (5), and, as consequence, will indicate that the nozzle (1) is inserted and secured into the receptacle.

(15) The contact detection mechanism of the shown embodiment comprises two plaques (7) and (8), isolated from one another and isolated from the nozzle body (1). An isolating material (11) surrounds the two plaques (7, 8) for that purpose. A third plaque (6) is located apart from and above them, not in contact with them in the nozzle no contact condition. The third plaque (6) is additionally isolated from the nozzle body (1). This third plaque (6) will be directly in contact with the rollers (12) of the receptacle. Two cables (9) and (10) connect the first and second plaques (7, 8), respectively and independently, to the computing device (50) that will analyze the information (pulse, voltage, mA) received. The resulting signals (25, 26) sent to computing device (50) will be for the first and for the second latch (5).

(16) When the nozzle (1) is inserted into the receptacle, the rollers (12) of the receptacle will be in contact with the latches (5) of the nozzle (1), and as a consequence, directly with the third plaque (6). The rollers (12) will exert a force on the latches (5) in order to maintain the nozzle (1) secured within the receptacle. As the rollers (12) are in contact with the latches (5), they will exert a force on the third plaque (6), and this third plaque will then be moved into contact simultaneously with the first and second plaques (7, 8), allowing thus continuity successively between the computing device (50), cable (9) connected to the first plaque (7), the third plaque (6), the second plaque (8), cable (10) connected to the second plaque (8) and finally to the computing device (50). This represents a closed circuit. As a consequence, this device will actuate as a switch. A current will be circulating in that circuit, allowing the computing device (50) to consider the circuit as closed, and therefore the nozzle (1) as in contact position with the receptacle. Once the nozzle (1) is removed from the receptacle, the rollers (12) no longer exert any force on the latches (5) and the third plaque (6), so that the first and second plaques (7, 8) will no longer be in contact with the third plaque. The circuit will be open, no current will be circulating, and the computing device (50) will consider the nozzle as not in contact.

(17) One or more contact detection mechanisms (14) detect the poppet valve (4) state.

(18) In the embodiment shown in FIG. 6 there is shown a load cell (14) that will measure the force of the poppet spring (13) and determine the position of the nozzle (1) within the receptacle, until it is fully inserted and secured. The resulting signal (30) will be transmitted to the computing device (50) through dedicated wiring.

(19) When the nozzle (1) is inserted into the receptacle, the poppet valve (4), which is a mobile part equipped with a spring (13), will be in contact with a fixed part of the receptacle. The poppet valve (4) will then open, and the spring (13) will be compressed, exerting a force on the load cell (14) on which the spring is seated. When the nozzle (1) is fully inserted into the receptacle and secured by the latches (5), the poppet valve (4) is opened and its displacement is the maximum, as well as the force exerted by the spring (13) on the load cell (14). From now on the maximum displacement will be called Xmax and the maximum force exerting by the spring will be called Fmax. The signal (30) from this load cell (14) will be transmitted to the computing device (50), which will detect a contact status of the nozzle (1) into the receptacle when the force read reaches a threshold, the threshold being equal or close to Fmax (to be determined by experimental testing). As soon as the nozzle (1) is removed from the receptacle, the poppet valve (4) will travel in the opposite direction, will leave the Xmax position and the spring (13) tension will decrease from Fmax. As consequence, the load cell will read a lower force, transmitted to computing device (50), which will declare a no contact status.

(20) The resulting contact signal (30) from the poppet valve (4) will be processed by the computing device (50) in combination with the rest of the signals.

(21) The computing device (50) will firstly analyze the signals (25, 26) coming from the latching state sensors (25, 26) that will be voted in order to obtain the latched status in the following way:

(22) If both signals from the latching state sensors (25, 26) are positive the latched status will be positive (latched).

(23) If one or more of the signals from the latching state sensors (25, 26) are negative the latched status will be negative.

(24) Then the computing device (50) will analyze the signal (20) from the first contact detecting mechanism, the latched status and the signal (30) from the valve (4) in accordance with the following table to produce the computed status (60):

(25) TABLE-US-00001 TABLE 1 Computed status after receiving the signals. Contact of the nozzle Latched Valve status (20) status (30) Computed status (60) Positive Positive Positive [60.1]: Positive/Contact (Pulse (latched) (Poppet Nozzle connected nominal received) valve condition. open) Negative [60.2]: Positive/Contact (Poppet Nozzle connected. Poppet valve valve shall be open and the signal closed) status [30] is considered failed. Maintenance action shall be done after the flight to restore the signal [30]. Negative Positive [60.3]: Negative/No contact (unlatched) (Poppet The nozzle is in the nominal valve position of connection and the open) poppet valve is fully open, but the latches cannot be latched. Therefore, a possible float out can occur. Although the refueling operation can be performed, additional precautions shall be taken by the boom operator. After the flight a maintenance action will be done to restore the system. Negative [60.4]: Negative/No contact (Poppet The nozzle is in a position close valve to the nominal contact, however, closed) the contact shall be aborted and new attempt shall be tried as a latching condition is not confirmed. Negative Positive Positive [60.5]: Positive/Contact (Pulse (latched) (Poppet This is considered a loss of pulse not valve signal, but the other signals are received) open) indicating that the contact is done. Operation can be done. Negative [60.6]: Negative/No contact (Poppet High probability of jammed valve nozzle. Emergency closed) disconnection shall be done. Negative Positive [60.7]: Negative/No contact (unlatched) (Poppet The nozzle is in the nominal valve position of connection but the open) latches cannot be latched. Therefore, a high probable float out can occur. Although the refueling operation can be performed, additional precautions shall be taken by the boom operator. After the flight a maintenance action will be done to restore the system Negative [60.8] Negative/No contact (Poppet Nominal no contact situation. valve closed)

(26) Table 1 identifies eight computed states which significantly improves the two states that the currently used systems can only discriminate.

(27) Therefore, there are output signals (60) to the tanker aircraft for aborting the refueling operation when the received signal from the third contact detecting mechanism are negative and at least the received signal between the first or the second contact detecting mechanisms are also negative.

(28) One of the advantages of the invention is that if the signals from the contact detecting mechanisms related to the latches (5) and the valve (4) are positive but the pulse coming from the coil (3) is negative, the computing device (50) will identify a failure in capturing the pulse but the contact status can be declared based on the rest of the contact detecting mechanisms. This way the system can transition from no-contact to contact, allowing the dispense operation in a safe condition. In the existing systems when the pulse is lost but the contact is really done, this would lead to an unsafe condition as the boom control system has wrong information, and the control laws cannot be adapted accordingly. Therefore, the present invention provides higher level of safety.

(29) Another advantage of the invention can be observed when the contact detection mechanisms related to the latches (5) provide a negative signal while the pulse received from the coil (3) is positive. In this case the output signal (60) can be used to advise the crew and/or the control system of a potential float out condition, giving the opportunity to make corrective actions, while the existing systems will consider this situation as a nominal contact. Therefore, the present invention increases the safety level of the refueling system.

(30) Another further advantage of the invention, which is not solved by any of the prior art documents, can be observed in the states in which the pulse and latch (5) signals are positive while the valve (4) signal is negative and the state in which the pulse and latch (5) signal are negative and the valve (4) signal is positive. With these states relevant information for diagnosis of the failure can be recorded, reducing the time of the subsequent maintenance actions, which in turn, reduce the maintenance costs.

(31) In this circumstance the tanker operator applies a protocol allowing the refueling operation but being prepared to react if the nozzle suddenly disconnects.

(32) While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.