Cross-Reference to Related Application

[0001] This application claims the benefit of priority to U.S. provisional patent application serial number 61/600,608, filed on February 18, 2012.

Field of the Invention

[0002] The present invention relates to systems for gathering and recording data regarding the operation of an aircraft. The invention may be used to outfit an existing aircraft with a new data recording system. Background of the Invention

[0003] Many aircraft operate flight data recorders ("FDRs") that are designed to accept analog data signals provided according to the ARINC 542A standard. An FDR that is configured according to ARINC 542A is a single-box recorder system that is able to accept analog signals directly from the instruments that produce the information signals. Unlike other FDRs, ARINC 542A FDRs do not require a separate flight data acquisition unit ("FDAU") for the acquisition and conversion of the analog signals. Instead, the ARINC 542A FDR includes its own internal analog-to-digital converter, thereby enabling the single- box solution.

[0004] Other aircraft operate FDRs that are designed to accept flight data signals provided by an FDAU, and many of those are configured according to the ARINC 573/717 standards. The ARINC 573/717 FDRs are digital systems, but many of these systems do not include features of more modern FDR systems.

[0005] Despite their limitations, these FDRs are used in a wide range of aircraft types, including airline, corporate, regional, and military transport aircraft. A significant limitation of these systems is the number of parameters that can be monitored. For example, the F1000 PN S703 and S903 FDRs, which operate according to ARINC 542A, have a maximum of 25 parameters that can be monitored via the analog signals. In addition, existing digital systems such as ARINC 573/717 are limited by the number of signals they can accept. There is a need in many aircraft to record information provided by additional signals, and those additional signals may be analog or digital. This need to record information provided by additional signals may arise from a desire to capture additional information for engineering and/or maintenance use, or may arise from modified regulatory requirements.

[0006] Also, production of ARINC 542A FDR systems has ceased. When an existing

ARINC 542A FDR is replaced with a more modern system, the new FDR system may be configured according to ARINC 573, 717, or 747 standards. Modern FDRs that are based on the ARINC 573, 717, or 747 standards are able to record many more parameters than an ARINC 542A FDR, but those modern FDRs are not a direct replacement for the older

ARINC 542A systems. Instead, upgrading an aircraft to an ARINC 573, 717 or 747 system currently requires modification of the aircraft in order to install a separate FDAU. Creating a new mounting location for the new FDAU is costly.

[0007] For example, some existing solutions to replace ARINC 542A FDRs require installation of a digital flight data acquisition unit ("DFDAU") and a solid state flight data recorder ("SSFDR"), each requiring its own mounting tray. As such, the single mounting tray used for an ARINC 542A FDR is not sufficient, and at least one new mounting tray is required by existing replacement systems. By requiring two mounting trays, such replacement systems require aircraft modification and consequently higher costs to the operator.

[0008] It would be useful to have a device that could be used to replace an ARINC

542A FDR and also that could be used to replace an ARINC 573/717 FDR, while also providing the ability to accept additional information signals. Having a single device that is suitable for replacing both types of FDRs without requiring the installation of a new mounting tray would enable easier, more efficient and lower cost replacement of aging FDRs.

Summary of the Invention

[0009] The invention may be embodied as an interface device (sometimes referred to as an "FDAIU" - Flight Data Acquisition Interface Unit). The interface device has (i) a footprint surface sized to fit the mounting tray, (ii) an inbound surface oriented substantially perpendicular to the footprint surface, (iii) an outbound surface substantially parallel to the inbound surface, and (iv) a platform surface substantially parallel to the footprint surface and sized to accept an FDR. The footprint surface may be shaped to match aspects of the mounting tray so that a close fit is achieved between the interface device and the mounting tray.

[0010] One or more receiving connectors may extend through the inbound surface, and these may be used to deliver information signals to electronics that are part of the interface device. One or more transmitting connectors may extend through the outbound surface, and these may be used to deliver information signals to the FDR.

[0011] The interface device may include at least one side surface oriented substantially perpendicular to the footprint surface and extending beyond the platform surface so as to form a receiving tray. Alternatively, the interface device may include at least one boundary surface extending substantially perpendicularly from the platform surface so as to form the receiving tray.

[0012] The interface device may include electronic circuitry. The electronic circuitry may have an analog-to-digital converter and/or a programmable microprocessor. The electronic circuitry may reside between the footprint surface and the platform surface. Or, electronic circuitry may reside between the inbound surface and the outbound surface. Or, electronic circuitry may reside in both of these locations.

[0013] The invention may be embodied as a flight data processing system having (a) a mounting tray, (b) an interface device supported by the mounting tray, and (c) an FDR supported by the interface device. The interface device may have the features described in the preceding paragraph. In this arrangement, the interface device resides between the mounting tray and the FDR.

Brief Description Of The Drawings [0014] For a fuller understanding of the nature and objects of the invention, reference should be made to the accompanying drawings and the subsequent description. Briefly, the drawings are:

Figure 1A and IB are each a schematic showing aspects of an interface device according to the present invention;

Figure 2 is an exploded side view showing an FDR, an interface device and a mounting tray;

Figure 3 is side view showing an FDR, an interface device and a mounting tray;

Figure 4 is a side view showing an FDR and an interface device;

Figure 5 is a rear view of an interface device;

Figure 6 is a front view of an interface device;

Figure 7 is a front view of an interface device with an FDR mounted

to the interface device;

Figure 8 is a front view of an interface device;

Figure 9 is a front view of an interface device with an FDR mounted

to the interface device;

Figure 10 is a schematic of an interface device depicting components

housed within the various surfaces of the interface device; and

Figures 11 A, 1 IB and 11C are each an oblique view of the interface

device shown in Figure 3.

Further Description of the Invention

[0015] The invention includes an interface device 10, which allows for the upgrade of existing and obsolete FDRs, while avoiding the need to make aircraft modifications. Using an interface device 10 according to the invention, it is possible to record information from a variety of sources, such as analog instruments, ARINC 429 buses, and ARINC 573/717 buses. To do so, an interface device 10 according to the invention receives information carried by inbound signals and derived from aircraft instruments, and assembles that information into an outbound signal that is sent to the FDR. The outbound signal provided by the interface device 10 may be configured according to ARINC 573/717. In this manner, the outbound signal from the interface device 10 may deliver information sourced from all of the inbound signals, including those signals that were handled by the previous FDR as well as signals that were not handled by the previous FDR.

[0016] Figures 1A and IB are schematics depicting aspects of an embodiment of an interface device 10 that is in keeping with the invention. The interface device 10 is capable of accepting many types of inbound signals 11, which may include: (a) signals from an analog ARINC 542A aircraft FDR installation 13A, (b) signals from an ARINC 429 bus 13B, and (c) signals from an ARINC 573/717 bus 13C. With reference to Figures 1A and IB, parameters provided by a previously existing system, which was configured to convey information according to an ARINC 717 data frame, are extracted, retained, and

supplemented with additional parameters, which may be provided via analog or ARINC-429 information signals. A new ARINC 717 data frame 16 is then created and transmitted in the form of an outbound signal 17 to a digital FDR 19, such as an ARINC 717 FDR or CVFDR (Cockpit Voice Flight Data Recorder).

[0017] An interface device 10 according to the invention, in combination with a replacement FDR 19 (such as a Model FA2100 flight data recorder manufactured by L3 Communications) can take the place of an ARINC 542A FDR or ARINC 573/717 FDR. Consequently, such an interface device 10 addresses the problem presented by the unavailability of ARINC 542A FDRs, and some ARINC 573/717 FDRs, as well as the un- supportability of existing FDRs due to parts obsolescence. Perhaps more importantly, the invention can be implemented using the existing mounting tray 22 that was previously used by the ARINC 542A FDR. The interface device 10 and new FDR 19 can be configured to have a "footprint" that is substantially the same or smaller than the footprint of the systems they replace.

[0018] For example, the interface device 10 may be configured to connect to the existing mounting tray 22, and to a new SSFDR 19 (designed to the ½ ATR short case dimensions) may be directly connected and mounted to the interface device 10. In this manner, the interface device 10 provides a physical interface between the existing FDR mounting tray 22, connectors 25 and analog wiring with a new digital FDR 19. Furthermore, the interface device 10 provides an electrical interface between the existing FDR mounting tray 22 and the new digital FDR 19. In this manner, the invention may provide a direct replacement for the ARINC 542A-capable FDR system by providing a system having the same or smaller dimensions as the FDR that is being replaced. Consequently, changes to the aircraft itself are either not needed, or are very minor.

[0019] Figure 2 is an exploded schematic showing a mounting tray 22, and interface device 10 according to the invention, and an FDR 19. Figure 3 shows these three components in a non-exploded format. Figure 4 shows the interface device 10 and FDR 19 of Figure 3 without the mounting tray 22. The interface device 10 has a footprint that is sized to fit in the existing mounting tray 22 of the aircraft, and provides a platform on which the new FDR 19 may be placed and/or mounted. When the FDR 19 is attached to the interface device 10, the external dimensions of the combined devices does not exceed the external dimensions of the FDR that is being replaced.

[0020] The specific arrangement depicted in Figures 2 and 3 uses an interface device

10 having a footprint that fits a ½ ATR 404 Long, and has a platform surface 28 similar to a ½ ATR short case. In order to receive inbound signals, one or more conductive receiving connectors 31 of the interface device 10 are positioned and configured to mate with conductive connectors 25 of the mounting tray 22. Also, in order to provide outbound signals, one or more conductive transmitting connectors 34 of the interface device 10 are positioned and configured to mate with the conductive connectors of the FDR 19. In this manner, the interface device 10 may be easily plugged into the mounting tray connectors 25, and the new FDR 19 may be easily plugged into the transmitting connectors 34 of the interface device 10. As such, the interface device 10 establishes a communications link between the existing mounting tray connectors 25 and the FDR 19. Thus, the interface device 10 receives the signals from the various aircraft instruments and provides

corresponding signals to the FDR 19. [0021] The interface device 10 may include a plurality of surfaces. Figures 2, 6 and 7 show a particular arrangement of these surfaces. Figures 11 A, 1 IB and 11C further illustrate the arrangement. When installed in a mounting tray 22, a footprint surface 37 of the interface device 10 may reside in close proximity to the mounting tray 22. [0022] An inbound surface 40 of the interface device 10 may be substantially perpendicular to the footprint surface 37. Conductive connectors, which may be the receiving connectors 31 of the interface device 10, may extend through the inbound surface 10, and these may be used to deliver information signals from aircraft instruments to the interface device 10. Although referred to herein as the "inbound surface", it should be noted that the signals and conductive connectors that cross the inbound surface 10 need not carry information to the interface device 10. The term "inbound surface" is used herein as a reminder that signals from aircraft instruments to the electronics 55 are delivered to the interface device 10 primarily at a location on the inbound surface 40 of the interface device 10. In most applications of the invention, the inbound surface 10 will face a portion of the mounting tray 22 that previously faced the FDR that is being replaced.

[0023] Fault status outputs, which indicate whether the FDR is functioning properly, may be provided on the inbound surface 40 of the interface device 10 in order to retain an existing FDR fault status indication in the aircraft. It should be noted that this is an example of an instance in which a signal being provided from the interface device 10 is made available at the inbound surface 40 of the interface device 10. In situations where an existing ARINC 542A installation utilizes pneumatic signals for altitude and airspeed parameters, pitot and static pressure connectors may be provided by the interface device 10 at a location that facilitates connection with the existing pitot and static lines.

[0024] An outbound surface 43 of the interface device 10 may be substantially parallel to the inbound surface 40. Conductive connectors which may be the transmitting connectors 34 of the interface device 10 may extend through the outbound surface 43, and these may be used to deliver information signals from the interface device 10 to the FDR 19. Although referred to herein as the "outbound surface", it should be noted that the signals and conductive connectors that cross the outbound surface need not carry information from the interface device 10. The term "outbound surface" is used as a reminder that signals from the electronics 55 to the FDR 19 are delivered primarily at a location on the outbound surface 43 of the interface device 10. Also, in most applications of the invention, the outbound surface 43 will face a portion of the new FDR 19.

[0025] A platform surface 28 of the interface device 10 may be substantially parallel to the footprint surface 37. Such an arrangement allows the interface device 10 to be placed in the mounting tray 22, and then slid in a direction substantially parallel to the orientation of the receiving connectors 31 of the interface device 10 so that the receiving connectors 31 are mated with conductive connectors of the mounting tray. Such an arrangement also allows the new FDR 19 to be placed on the platform surface 28 of the interface device 10, and then slid in a direction substantially parallel to the orientation of the transmitting connectors 34 of the interface device 10 so that the transmitting connectors 34 mate with the conductive connectors of the FDR 19. Consequently, installation of the interface device 10 and FDR 19 is accomplished easily, quickly, and by utilizing space that was previously used during installation of the previous FDR. In this manner, the aircraft need not be modified in order to accommodate installation and operation of the interface device 10 and the new FDR 19.

[0026] Figures 8 and 9 show an interface device 10 having two side surfaces 46, which are oriented substantially perpendicular to the footprint surface 37. A portion of each side surface 46 may extend beyond the platform surface 28. The portion of each side surface 46 that extends beyond the platform surface 28 is referred to herein as a boundary surface 49. The platform surface 28, outbound surface 43, and boundary surfaces 49 provide an area that receives the FDR 19, enables the FDR 19 to be properly aligned so that the transmitting connectors 34 are aligned with conductive connectors of the FDR 19 prior to mating those sets of connectors, and the boundary surfaces 49 keep the FDR 19 from moving in a side-to- side fashion, thereby serving to limit movement of the FDR 19 relative to the interface device 10 when the aircraft is moving. The area formed by the platform surface 28, outbound surface 43 and boundary surfaces 49 may be thought of as a receiving tray 52 that holds the FDR 19 in a proper position. [0027] In an alternative embodiment of the invention (see Figs. 6 and 7), the boundary surfaces 49 may be integral with the platform surface 28 rather than the side surfaces 46. In this embodiment, a receiving tray 52 for holding the FDR 19 in a proper position is formed by the platform surface 28, the boundary surfaces 49, and the outbound surface 43. In that arrangement, the boundary surfaces 49 extend substantially

perpendicularly from the platform surface 28, and an external surface of a side surface 46 may be flush with part of a boundary surface 49 so as to provide a smooth transition between the side surfaces 46 and boundary surfaces 49.

[0028] The interface device 10 may be configured to comply with standard ARINC

542A and ARINC 573 specifications for both physical and electrical specifications, including all pneumatic, discrete, AC inputs, and DC inputs. In such an interface device 10, electronic circuitry 55 may be provided for processing received signals from instruments on the aircraft. The electronic circuitry 55 may include an analog-to-digital converter 58, which accepts existing analog instrument information signals and performs an analog-to-digital conversion of the received signals. The digital signals produced by the electronic circuitry 55 of interface device 10 and provided to the FDR 19 may be formatted according to ARINC 717. The electronic circuitry 55 in the interface device 10 (that accepts signals via the receiving connectors 31, transforms the received signals, and provides the transformed signals via the transmitting connectors 34) may be located between the footprint surface 37 and the platform surface 28, or between the inbound surface 40 and the outbound surface 43, or both.

[0029] The electronic circuitry 55 in the interface device 10 may include a programmable microprocessor 61, which can be used to tailor a particular interface device 10 to a particular aircraft. For example, if an aircraft has the ability to provide a global positioning signal to the interface device 10, then the interface device 10 may be programmed using the microprocessor 61 to accept the global position information provided by the signal, and programmed to include that information in the outbound signal that is provided to the FDR 19. [0030] In addition, the inbound signals delivered to the interface device 10 may be sampled by the interface device 10 at much higher rates than those specified in ARINC 542A. Higher sample rates may be desired for high performance aircraft in order to provide much higher resolution for parameters such as stick movement, acceleration parameters, pitch and roll, as well as other parameters.

[0031] Size and weight of the interface device 10 in combination with the

replacement FDR may be configured to be no greater than the size and weight of an existing ARINC 542A FDR. Toward this end, the interface device 10 may provide a mounting location for the FDR 19 that is similar to that provided by standard ½ ATR Short case configurations, and thereby afford the use of commercially available ("off the shelf) FDRs 19 in conjunction with the interface device 10 in an aircraft without needing to replace the existing mounting tray 22 or making modifications to the aircraft in order to accommodate the new FDR. It will now be recognized that for most orientations of the aircraft, the mounting tray 22 physically supports the interface device 10, and the interface device 10 physically supports the FDR 19.

[0032] Although the present invention has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present invention may be made without departing from the spirit and scope of the present invention. Hence, the present invention is deemed limited only by the appended claims and the reasonable interpretation thereof.