Patent Publication Number: US-10764747-B2

Title: Key management for wireless communication system for communicating engine data

Description:
PRIORITY CLAIM 
     The present application claims the benefit of priority of U.S. Provisional Patent Application No. 62/356,633, entitled “KEY MANAGEMENT FOR WIRELESS COMMUNICATION SYSTEM FOR COMMUNICATING ENGINE DATA,” filed Jun. 30, 2016, which is incorporated herein by reference for all purposes. 
    
    
     FIELD 
     The present subject matter relates generally to aviation systems. 
     BACKGROUND 
     An aerial vehicle can include one or more engines for propulsion of the aerial vehicle. The one or more engines can include and/or can be in communication with one or more electronic engine controllers (EECs). The one or more EECs can record data related to the one or more engines. If the data resides on the EECs, then it can be difficult for a ground system to use the data. Automated engine data transfer replaces manual data retrieval and increases the availability of data at the ground system. 
     BRIEF DESCRIPTION 
     Aspects and advantages of embodiments of the present disclosure will be set forth in part in the following description, or may be learned from the description, or may be learned through practice of the embodiments. 
     One example aspect of the present disclosure is directed to a wireless communication unit configured to be located in a nacelle associated with an engine of an aerial vehicle. The wireless communication unit can include one or more memory devices. The wireless communication unit can include one or more processors. The one or more processors can be configured to generate a pair of keys, wherein one of the pair of keys is a private key, and wherein one of the pair of keys is a public key. The one or more processors can be configured to transmit the public key to a first remote computing device, wherein the first remote computing device transmits the public key to a second remote computing device. The one or more processors can be configured to receive a host key from the first remote computing device, wherein the first remote computing device received the host key from the second remote computing device. The one or more processors can be configured to access the second remote computing device using the private key. The one or more processors can be configured to verify a request from the second remote computing device using the host key. 
     Other example aspects of the present disclosure are directed to systems, methods, aircrafts, engines, controllers, devices, non-transitory computer-readable media for recording and communicating engine data. Variations and modifications can be made to these example aspects of the present disclosure. 
     These and other features, aspects and advantages of various embodiments will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the related principles. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Detailed discussion of embodiments directed to one of ordinary skill in the art are set forth in the specification, which makes reference to the appended figures, in which: 
         FIG. 1  depicts an aerial vehicle according to example embodiments of the present disclosure; 
         FIG. 2  depicts an engine according to example embodiments of the present disclosure; 
         FIG. 3  depicts a wireless communication system according to example embodiments of the present disclosure; 
         FIG. 4  depicts a flow diagram of an example method according to example embodiments of the present disclosure; 
         FIG. 5  depicts a computing system for implementing one or more aspects according to example embodiments of the present disclosure; and 
         FIG. 6  depicts a sequence diagram of an example method according to example embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Reference now will be made in detail to embodiments, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the embodiments, not limitation of the embodiments. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
     As used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. The use of the term “about” in conjunction with a numerical value refers to within 25% of the stated amount. 
     Example aspects of the present disclosure are directed to methods and systems for recording and communicating engine data on an aerial vehicle. The aerial vehicle can include one or more engines for operations, such as propulsion of the aerial vehicle. The one or more engines can include and/or be in communication with one or more electronic engine controllers (EECs). 
     According to example embodiments of the present disclosure, the one or more engines and/or the one or more EECs can include and/or can be in communication with one or more wireless communication units (WCUs). During flight or other operation of the aerial vehicle, the one or more EECs can record data related to the one or more engines and can communicate (e.g., transmit, send, push, etc.) the data to the one or more WCUs, where the WCUs can store the data in a memory. Each EEC can communicate the data to its own associated WCU. In addition and/or in the alternative, each EEC can communicate data to a single WCU located on the aerial vehicle. Upon the occurrence of a particular trigger condition (e.g., flight phase transition), the one or more WCUs can communicate the data to a ground system over a wireless network, such as a cellular network. 
     In some embodiments, the WCU can be adaptable for communication with the EEC via an interface. The interface can be a Telecommunications Industry Association (TIA) TIA-485 interface, an Ethernet interface, an Aeronautical Radio INC (ARINC) 664 interface, an RS-232 interface, etc. The WCU can be adaptable for communication with the ground system via an antenna. The WCU can transmit information received from the EEC to the ground system. The ground system can use the information received from the WCU to determine a status (e.g., state, health, etc.) of an engine associated with the WCU. In addition, the WCU can be adaptable for communication with a portable maintenance access terminal (PMAT) for maintenance. 
     The WCU can have a need for a pair of encryption keys. For example, the WCU can be new and need a first pair of encryption keys. As another example, a pair of encryption keys currently stored by the WCU can expire. According to example embodiments of the present disclosure, the WCU can generate a pair of encryption keys. The pair of encryption keys can include a public key and a private key. The WCU can transmit (e.g., send, transfer, etc.) the public key to a secure key server. The secure key server can be addressable by a fixed Internet Protocol (IP) address. The WCU can login to the secure key server with a login and/or a password. 
     The secure key server can receive one or more server host keys from one or more destination servers. The one or more destination servers can communicate via Secure Shell (SSH) using the one or more server host keys and/or the pair of keys. The one or more destination servers can be addressable at one or more fixed IP addresses. The one or more destination servers can be protected with a password. The WCU can receive the one or more server host keys from the secure key server. The one or more destination servers can receive the public key from the secure key server using a transfer protocol that uses SSH to encrypt messages, such as Secure File Transfer Protocol (SFTP), Secure Copy (SCP), etc. 
     The WCU can transmit a Domain Name System (DNS) query to a DNS server. The DNS server can transmit a DNS response to the WCU. The WCU can receive an IP address for a closest destination server of the one or more destination servers. A determination of the closest destination server can be made based on a provided cell location. The WCU can access the closest destination server through a Secure Shell (SSH) tunnel with the private key. The WCU can use the server host key to verify the identity of the closest destination server. The WCU can log into a closest destination file transfer protocol (FTP) server with a username and/or a password. The WCU can receive a Login acknowledgement from the closest destination server. The WCU can initiate a bulk transfer of data to the closest destination server. The closest destination server can forward the data to a database. In an embodiment, any data transmitted to any of the one or more destination servers can be forwarded to the database. 
     One example aspect of the present disclosure is directed to a wireless communication unit configured to be located in a nacelle associated with an engine of an aerial vehicle. The wireless communication unit can include one or more memory devices. The wireless communication unit can include one or more processors. The one or more processors can be configured to generate a pair of keys, wherein one of the pair of keys is a private key, and wherein one of the pair of keys is a public key. The one or more processors can be configured to transmit the public key to a first remote computing device, wherein the first remote computing device transmits the public key to a second remote computing device. The one or more processors can be configured to receive a host key from the first remote computing device, wherein the first remote computing device received the host key from the second remote computing device. The one or more processors can be configured to access the second remote computing device using the private key. The one or more processors can be configured to verify a request from the second remote computing device using the host key. 
     In an embodiment, the wireless communication unit is associated with an engine. In an embodiment, the wireless communication unit is associated with an aerial vehicle. In an embodiment, the first remote computing device is associated with a ground system. In an embodiment, the second remote computing device is associated with a ground system. In an embodiment, the first remote computing device is a secure key server addressable by a fixed Internet Protocol address. In an embodiment, the second remote computing device is a destination server addressable by a fixed Internet Protocol address. In an embodiment, the one or more processors of the wireless communication unit are further configured to initiate a bulk transfer of data to the destination server. In an embodiment, the destination server forwards the transferred data to a third remote computing device. In an embodiment, the third remote computing device includes a data lake. 
     One example aspect of the present disclosure is directed to a method for key management. The method includes generating, by one or more local computing devices configured to be located in a nacelle associated with an engine of an aerial vehicle, a pair of keys, wherein one of the pair of keys is a private key, and wherein one of the pair of keys is a public key. The method includes transmitting, by the one or more local computing devices, the public key to a first remote computing device, wherein the first remote computing device transmits the public key to a second remote computing device. The method includes receiving, by the one or more local computing devices, a host key from the first remote computing device, wherein the first remote computing device received the host key from the second remote computing device. The method includes accessing, by the one or more local computing devices, the second remote computing device using the private key. The method includes verifying, by the one or more local computing devices, a request from the second remote computing device using the host key. 
     In an embodiment, a wireless communication unit includes the one or more local computing devices. In an embodiment, the wireless communication unit is associated with an engine. In an embodiment, the wireless communication unit is associated with an aerial vehicle. In an embodiment, the first remote computing device is associated with a ground system. In an embodiment, the second remote computing device is associated with a ground system. In an embodiment, the first remote computing device is a secure key server addressable by a fixed Internet Protocol address. In an embodiment, the second remote computing device is a destination server addressable by a fixed Internet Protocol address. In an embodiment, the method further includes initiating a bulk transfer of data to the destination server. In an embodiment, the destination server forwards the transferred data to a third remote computing device. In an embodiment, the third remote computing device includes a data lake. 
     Another example aspect of the present disclosure is directed to a system for key management. The system can include a wireless communication unit configured to be located in a nacelle associated with an engine of an aerial vehicle. The wireless communication unit can include one or more memory devices. The wireless communication unit can include one or more processors. The one or more processors can be configured to generate a pair of keys, wherein one of the pair of keys is a private key, and wherein one of the pair of keys is a public key. The one or more processors can be configured to transmit the public key to a first remote computing device, wherein the first remote computing device transmits the public key to a second remote computing device. The one or more processors can be configured to receive a host key from the first remote computing device, wherein the first remote computing device received the host key from the second remote computing device. The one or more processors can be configured to access the second remote computing device using the private key. The one or more processors can be configured to verify a request from the second remote computing device using the host key. 
     In an embodiment, the wireless communication unit is associated with an engine. In an embodiment, the wireless communication unit is associated with an aerial vehicle. In an embodiment, the first remote computing device is associated with a ground system. In an embodiment, the second remote computing device is associated with a ground system. In an embodiment, the first remote computing device is a secure key server addressable by a fixed Internet Protocol address. In an embodiment, the second remote computing device is a destination server addressable by a fixed Internet Protocol address. In an embodiment, the one or more processors of the wireless communication unit are further configured to initiate a bulk transfer of data to the destination server. In an embodiment, the destination server forwards the transferred data to a third remote computing device. In an embodiment, the third remote computing device includes a data lake. 
     One example aspect of the present disclosure is directed to an aerial vehicle. The aerial vehicle includes a wireless communication unit. The wireless communication unit can include one or more memory devices. The wireless communication unit can include one or more processors. The one or more processors can be configured to generate a pair of keys, wherein one of the pair of keys is a private key, and wherein one of the pair of keys is a public key. The one or more processors can be configured to transmit the public key to a first remote computing device, wherein the first remote computing device transmits the public key to a second remote computing device. The one or more processors can be configured to receive a host key from the first remote computing device, wherein the first remote computing device received the host key from the second remote computing device. The one or more processors can be configured to access the second remote computing device using the private key. The one or more processors can be configured to verify a request from the second remote computing device using the host key. 
     In an embodiment, the wireless communication unit is associated with an engine. In an embodiment, the first remote computing device is associated with a ground system. In an embodiment, the second remote computing device is associated with a ground system. In an embodiment, the first remote computing device is a secure key server addressable by a fixed Internet Protocol address. In an embodiment, the second remote computing device is a destination server addressable by a fixed Internet Protocol address. In an embodiment, the one or more processors of the wireless communication unit are further configured to initiate a bulk transfer of data to the destination server. In an embodiment, the destination server forwards the transferred data to a third remote computing device. In an embodiment, the third remote computing device includes a data lake. 
       FIG. 1  depicts a block diagram of an aerial vehicle  100  according to example embodiments of the present disclosure. The aerial vehicle  100  can include one or more engines  102 . The one or more engines  102  can cause operations, such as propulsion, of the aerial vehicle  100 . An engine  102  can include a nacelle  50  for housing components. An engine  102  can be a gas turbine engine. A gas turbine engine can include a fan and a core arranged in flow communication with one another. Additionally, the core of the gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air is provided from the fan to an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gases through the turbine section drives the turbine section and is then routed through the exhaust section, e.g., to atmosphere. 
     The one or more engines  102  can include and/or be in communication with one or more electronic engine controllers (EECs)  104 . The one or more engines  102  and/or the one or more EECs  104  can include and/or be in communication with one or more wireless communication units (WCUs)  106 . The one or more EECs  104  can record data related to the one or more engines  102  and communicate (e.g., transmit, send, push, etc.) the data to the one or more WCUs  106 . The one or more WCUs  106  can communicate the data to a ground system, via, for instance, an antenna positioned and configured within the nacelle  50 . The one or more WCUs  106  can be located within a nacelle  50  housing an engine  102  or another location on the aerial vehicle  100 . 
       FIG. 2  depicts an engine  102  according to example embodiments of the present disclosure. The engine  102  can be one of the one or more engines  102  on the aerial vehicle  100  in  FIG. 1 . More particularly, for the embodiment of  FIG. 2 , the engine  102  is configured as a gas turbine engine, or rather as a high-bypass turbofan jet engine  102 , referred to herein as “turbofan engine  102 .” Those of ordinary skill in the art, using the disclosures provided herein, will understand that WCUs can be used in conjunction with other types of propulsion engines without deviating from the scope of the present disclosure, including engines associated with helicopters and propellers. 
     As shown in  FIG. 2 , the turbofan engine  102  defines an axial direction A (extending parallel to a longitudinal centerline  13  provided for reference), a radial direction R, and a circumferential direction (not shown) extending about the axial direction A. In general, the turbofan includes a fan section  14  and a core turbine engine  16  disposed downstream from the fan section  14 . 
     The exemplary core turbine engine  16  depicted generally includes a substantially tubular outer casing  18  that defines an annular inlet  20 . The outer casing  18  encases and the core turbine engine  16  includes, in serial flow relationship, a compressor section including a booster or low pressure (LP) compressor  22  and a high pressure (HP) compressor  24 ; a combustion section  26 ; a turbine section including a high pressure (HP) turbine  28  and a low pressure (LP) turbine  30 ; and a jet exhaust nozzle section  32 . A high pressure (HP) shaft or spool  34  drivingly connects the HP turbine  28  to the HP compressor  24 . A low pressure (LP) shaft or spool  36  drivingly connects the LP turbine  30  to the LP compressor  22 . Accordingly, the LP shaft  36  and HP shaft  34  are each rotary components, rotating about the axial direction A during operation of the turbofan engine  102 . 
     In order to support such rotary components, the turbofan engine includes a plurality of air bearings  80  attached to various structural components within the turbofan engine  102 . Specifically, for the embodiment depicted the bearings  80  facilitate rotation of, e.g., the LP shaft  36  and HP shaft  34  and dampen vibrational energy imparted to bearings  80  during operation of the turbofan engine  102 . Although the bearings  80  are described and illustrated as being located generally at forward and aft ends of the respective LP shaft  36  and HP shaft  34 , the bearings  80  may additionally, or alternatively, be located at any desired location along the LP shaft  36  and HP shaft  34  including, but not limited to, central or mid-span regions of the shafts  34 ,  36 , or other locations along shafts  34 ,  36  where the use of conventional bearings  80  would present significant design challenges. Further, bearings  80  may be used in combination with conventional oil-lubricated bearings. For example, in one embodiment, conventional oil-lubricated bearings may be located at the ends of shafts  34 ,  36 , and one or more bearings  80  may be located along central or mid-span regions of shafts  34 ,  36 . 
     Referring still to the embodiment of  FIG. 2 , the fan section  14  includes a fan  38  having a plurality of fan blades  40  coupled to a disk  42  in a spaced apart manner. As depicted, the fan blades  40  extend outwardly from disk  42  generally along the radial direction R. Each fan blade  40  is rotatable relative to the disk  42  about a pitch axis P by virtue of the fan blades  40  being operatively coupled to a suitable pitch change mechanism  44  configured to collectively vary the pitch of the fan blades  40  in unison. The fan blades  40 , disk  42 , and pitch change mechanism  44  are together rotatable about the longitudinal axis  13  by LP shaft  36  across a power gear box  46 . The power gear box  46  includes a plurality of gears for adjusting the rotational speed of the fan  38  relative to the LP shaft  36  to a more efficient rotational fan speed. More particularly, the fan section includes a fan shaft rotatable by the LP shaft  36  across the power gearbox  46 . Accordingly, the fan shaft may also be considered a rotary component, and is similarly supported by one or more bearings. 
     Referring still to the exemplary embodiment of  FIG. 2 , the disk  42  is covered by a rotatable front hub  48  aerodynamically contoured to promote an airflow through the plurality of fan blades  40 . Additionally, the exemplary fan section  14  includes an annular fan casing or outer nacelle  50  that circumferentially surrounds the fan  38  and/or at least a portion of the core turbine engine  16 . The exemplary nacelle  50  is supported relative to the core turbine engine  16  by a plurality of circumferentially-spaced outlet guide vanes  52 . Moreover, a downstream section  54  of the nacelle  50  extends over an outer portion of the core turbine engine  16  so as to define a bypass airflow passage  56  therebetween. 
     During operation of the turbofan engine  102 , a volume of air  58  enters the turbofan through an associated inlet  60  of the nacelle  50  and/or fan section  14 . As the volume of air  58  passes across the fan blades  40 , a first portion of the air  58  as indicated by arrows  62  is directed or routed into the bypass airflow passage  56  and a second portion of the air  58  as indicated by arrow  64  is directed or routed into the core air flowpath, or more specifically into the LP compressor  22 . The ratio between the first portion of air  62  and the second portion of air  64  is commonly known as a bypass ratio. The pressure of the second portion of air  64  is then increased as it is routed through the high pressure (HP) compressor  24  and into the combustion section  26 , where it is mixed with fuel and burned to provide combustion gases  66 . 
     The combustion gases  66  are routed through the HP turbine  28  where a portion of thermal and/or kinetic energy from the combustion gases  66  is extracted via sequential stages of HP turbine stator vanes  68  that are coupled to the outer casing  18  and HP turbine rotor blades  70  that are coupled to the HP shaft or spool  34 , thus causing the HP shaft or spool  34  to rotate, thereby supporting operation of the HP compressor  24 . The combustion gases  66  are then routed through the LP turbine  30  where a second portion of thermal and kinetic energy is extracted from the combustion gases  66  via sequential stages of LP turbine stator vanes  72  that are coupled to the outer casing  18  and LP turbine rotor blades  74  that are coupled to the LP shaft or spool  36 , thus causing the LP shaft or spool  36  to rotate, thereby supporting operation of the LP compressor  22  and/or rotation of the fan  38 . 
     The combustion gases  66  are subsequently routed through the jet exhaust nozzle section  32  of the core turbine engine  16  to provide propulsive thrust. Simultaneously, the pressure of the first portion of air  62  is substantially increased as the first portion of air  62  is routed through the bypass airflow passage  56  before it is exhausted from a fan nozzle exhaust section  76  of the turbofan, also providing propulsive thrust. The HP turbine  28 , the LP turbine  30 , and the jet exhaust nozzle section  32  at least partially define a hot gas path  78  for routing the combustion gases  66  through the core turbine engine  16 . 
     It should be appreciated, however, that the exemplary turbofan engine  102  depicted in  FIG. 2  is provided by way of example only, and that in other exemplary embodiments, the turbofan engine  102  may have any other suitable configuration. It should also be appreciated, that in still other exemplary embodiments, aspects of the present disclosure may be incorporated into any other suitable gas turbine engine or other propulsion engine. For example, in other exemplary embodiments, aspects of the present disclosure may be incorporated into, e.g., a turboprop engine, a turboshaft engine, or a turbojet engine. Further, in still other embodiments, aspects of the present disclosure may be incorporated into any other suitable turbomachine, including, without limitation, a steam turbine, a turboshaft, a centrifugal compressor, and/or a turbocharger. 
     According to example aspects of the present disclosure, the engine  102  can include an electronic engine controller (EEC)  104 . The EEC  104  can record operational and performance data for the engine  102 . The EEC  104  can be in communication with a wireless communication unit (WCU)  106 . The WCU  106  can be mounted on the engine  102 . The EEC  104  and the WCU  106  can communicate using wireless and/or wired communications. In some embodiments, the communication with the EEC  104  and the WCU  106  can be one-way communication (e.g., the EEC  104  to the WCU  106 ). In some embodiments, the communication with the EEC  104  and the WCU  106  can be two-way communication. The WCU  106  can be located on the engine or elsewhere on the aircraft. The nacelle  50  can include an antenna (not shown). In another aspect, the antenna can be integrated with the WCU  106 . In another aspect, the antenna can be located elsewhere on the aircraft and used by the WCU and optionally other devices. 
       FIG. 3  depicts a wireless communication system (WCS)  300  according to example embodiments of the present disclosure. The system  300  can include a wireless communication unit (WCU)  302 . The WCU  302  can be the WCU  106  of  FIGS. 1 and 2 . The WCU  302  can be in communication with an electronic engine controller (EEC)  304  over a suitable interface  306 . The EEC  304  can be the same as the EEC  104  of  FIGS. 1 and 2 . In some embodiments, the interface  306  can be, for instance, a Telecommunications Industry Association (TIA) TIA-485 interface  306 . 
     In particular implementations, the WCU  302  and the EEC  304  can communicate via a connection  308  with, for instance, the TIA-485 interface  306 . The connection  308  can, for example, accommodate other interfaces, such as an Ethernet connection, a wireless connection, or other interface. The connection  308  can be, for example, a wired connection, such as, for example, an Ethernet connection. The connection  308  can be, for example, a wireless connection, such as, for example, a BlueTooth® connection. The WCU  302  can transmit addressing (e.g., memory location, bit size, etc.) information and/or acknowledgements  310  to the EEC  304  via the connection  308 . The WCU  302  can receive data  312  from the EEC  304  via the connection  308  and can store the data in one or more memory device. The data  312  can be, for instance, continuous engine operation data, such as thrust level inputs, engine response to thrust level inputs, vibration, flameout, fuel consumption, ignition state, N1 rotation, N2 rotation, N3 rotation, anti-ice capability, fuel filter state, fuel valve state, oil filter state, etc. 
     The WCU  302  can be configured to communicate the data  312  over a wireless network via an antenna  314  upon the occurrence of one or more trigger conditions, such as trigger conditions based on signals indicative of an aircraft being on the ground or near the ground. In some embodiments, the antenna  314  can be integrated into the WCU  302 . In some embodiments, the WCU  302  can include a radio frequency (RF) interface  316 . In an embodiment, the antenna  314  can be in communication with the RF interface  316  via an RF cable  318 . In an embodiment, the antenna  314  can be placed in the nacelle  50  of an aircraft  102 . The nacelle  50  of an aerial vehicle  100  can be made of conductive materials, which can obstruct cellular reception and transmission. In some embodiments, the antenna can be a directional antenna that is oriented near one or more gaps in the nacelle  50  to permit the antenna  314  to communicate directionally outside of the nacelle  50  when the aerial vehicle  100  is landing or upon the occurrence of other trigger conditions. 
     In some embodiments, the WCU  302  can include an interface for communicating with a portable maintenance access terminal (PMAT)  320 . The access terminal can be implemented, for instance, on a laptop, tablet, mobile device, or other suitable computing device. The interface can be, for instance, a Generic Stream Encapsulation (GSE) interface  322  or other suitable interface. The PMAT  320  can be used by a maintenance person to calibrate, troubleshoot, initialize, test, etc. the WCU  302 . 
     The WCU  302  can communicate using wireless communication. The wireless communication can be performed using any suitable wireless technique and/or protocol. For example, the wireless communication can be performed using peer-to-peer communications, network communications, cellular-based communications, satellite-based communications, etc. As another example, the wireless communications can be performed using Wi-Fi, Bluetooth, ZigBee, etc. 
       FIG. 4  depicts a flow diagram of an example method ( 400 ) for key management. The method of  FIG. 4  can be implemented using, for instance, the WCU  302  of  FIG. 3 .  FIG. 4  depicts steps performed in a particular order for purposes of illustration and discussion. Those of ordinary skill in the art, using the disclosures provided herein, will understand that various steps of any of the methods disclosed herein can be adapted, modified, rearranged, or modified in various ways without deviating from the scope of the present disclosure. 
     At ( 402 ), a pair of keys can be generated. For instance, the WCU  302  can generate a pair of keys. The WCU  302  can be associated with an engine and/or an aerial vehicle. One of the pair of keys can include a private key. One of the pair of keys can include a public key. The public key can be a key obtainable and usable by any party for encrypting a message to the WCU  302 . The private key can be a key known only by the WCU  302  that is used to decrypt messages encrypted by the public key. At ( 404 ), the public key can be transmitted to a first remote computing device. For instance, the WCU  302  can transmit the public key to a key server. The first remote computing device can be associated with a ground system. The first remote computing device can be a secure key server addressable by a fixed Internet Protocol address. The first remote computing device can transmit the public key to a second remote computing device. The second remote computing device can be associated with a ground system. The second remote computing device can be a destination server addressable by a fixed Internet Protocol address. 
     At ( 406 ), a host key can be received from the first remote computing device. For instance, the WCU  302  can receive a host key from the key server. The host key can have been received by the first remote computing device from the second remote computing device. The host key can be a public key associated with the second remote computing device. At ( 408 ), the second remote computing device can be accessed using the private key. For instance, the WCU  302  can access the second remote computing device using the private key. At ( 410 ), a request from the second remote computing device can be verified using the host key. For instance, the WCU  302  can verify a request from the second remote computing device using the host key. Optionally, a bulk transfer of data to the destination server can be initiated. For instance, the WCU  302  can initiate a bulk transfer of data to the destination server. In an embodiment, the destination server can forward the transferred data to a third remote computing device. In an embodiment, the third remote computing device can include a data lake. In an embodiment, the third remote computing device can include a data storage repository. In an embodiment, the third remote computing device can include a database. 
       FIG. 5  depicts a block diagram of an example computing system that can be used to implement a wireless communication unit (WCU)  500 , such as WCU  302 , or other systems according to example embodiments of the present disclosure. As shown, the WCU  500  can include one or more computing device(s)  502 . The one or more computing device(s)  502  can include one or more processor(s)  504  and one or more memory device(s)  506 . The one or more processor(s)  504  can include any suitable processing device, such as a microprocessor, microcontroller, integrated circuit, logic device, or other suitable processing device. The one or more memory device(s)  506  can include one or more computer-readable media, including, but not limited to, non-transitory computer-readable media, RAM, ROM, hard drives, flash drives, or other memory devices. 
     The one or more memory device(s)  506  can store information accessible by the one or more processor(s)  504 , including computer-readable instructions  508  that can be executed by the one or more processor(s)  504 . The instructions  508  can be any set of instructions that when executed by the one or more processor(s)  504 , cause the one or more processor(s)  504  to perform operations. The instructions  508  can be software written in any suitable programming language or can be implemented in hardware. In some embodiments, the instructions  508  can be executed by the one or more processor(s)  504  to cause the one or more processor(s)  504  to perform operations, such as the operations for recording and communicating engine data, as described with reference to  FIG. 4 , and/or any other operations or functions of the one or more computing device(s)  502 . 
     The memory device(s)  506  can further store data  510  that can be accessed by the processors  504 . For example, the data  510  can include data associated with engine performance, engine operation, engine failure, errors in engine performance, errors in engine operation, errors in engine behavior, expected engine behavior, actual engine behavior, etc., as described herein. The data  510  can include one or more table(s), function(s), algorithm(s), model(s), equation(s), etc. according to example embodiments of the present disclosure. 
     The one or more computing device(s)  502  can also include a communication interface  512  used to communicate, for example, with the other components of system. For example, the communication interface  512  can accommodate communications with the EEC  304 , the antenna  314 , the PMAT  320 , a ground control system, other WCUs  302 , a central computing device, any other device, and/or any combination of the foregoing. The communication interface  512  can include any suitable components for interfacing with one or more network(s), including for example, transmitters, receivers, transceivers, ports, controllers, antennas, or other suitable components. 
       FIG. 6  depicts a sequence diagram of an example method according to example embodiments of the present disclosure. At ( 612 ), the WCU  600  can have a need for a pair of encryption keys. For example, the WCU  600  can be new and need a first pair of encryption keys. As another example, a pair of encryption keys currently stored by the WCU  600  can expire. At ( 614 ), the WCU  600  can generate a pair of encryption keys. The pair of encryption keys can include a public key and a private key. The WCU  600  can transmit (e.g., send, transfer, etc.) the public key to a secure key server  602 . The secure key server can be addressable by a fixed Internet Protocol (IP) address. At ( 616 ), the WCU  600  can login to the secure key server  602  with a login and/or a password. 
     The secure key server  602  can receive one or more server host keys from one or more destination servers  606 ,  608 ,  610 . The one or more destination servers  606 ,  608 ,  610  can communicate via Secure Shell (SSH) using the one or more server host keys and/or the pair of keys. The one or more destination servers  606 ,  608 ,  610  can be addressable at one or more fixed IP addresses. The one or more destination servers  606 ,  608 ,  610  can be protected with a password. At ( 618 ), the WCU  600  can receive the one or more server host keys from the secure key server  602 . At ( 620 ), the one or more destination servers  606 ,  608 ,  610  can receive the public key from the secure key server  602  using a transfer protocol that uses SSH to encrypt messages, such as Secure File Transfer Protocol (SFTP), Secure Copy (SCP), etc. 
     At ( 622 ), the WCU  600  can transmit a Domain Name System (DNS) query to a DNS server  604 . Also at ( 622 ), the DNS server  604  can transmit a DNS response to the WCU  600 . At ( 624 ), the WCU  600  can receive an IP address for a closest destination server of the one or more destination servers  606 ,  608 ,  610 . A determination of the closest destination server  608  can be made based on a provided cell location. The WCU  600  can access the closest destination server  608  through a Secure Shell (SSH) tunnel with the private key. The WCU  600  can use the server host key to verify the identity of the closest destination server  608 . The WCU  600  can log into a closest destination file transfer protocol (FTP) server  608  with a username and/or a password. The WCU  600  can receive a Login acknowledgement from the closest destination server  608 . The WCU  600  can initiate a bulk transfer of data to the closest destination server  608 . At ( 626 ), the closest destination server  608  can forward the data to a data lake  628 . In an embodiment, any data transmitted to any of the one or more destination servers  606 ,  608 ,  610  can be forwarded to the data lake  628 . 
     Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the present disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing. Example aspects of the present disclosure are discussed with referenced to aerial vehicles. Those of ordinary skill in the art, using the disclosures provided herein, will understand that example aspects of the present disclosure can be used with other vehicles having engines 
     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 include 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.