UAS Beyond Line of Sight – Boeing Little Bird

The Boeing little bird (H-6U) is an unmanned helicopter based on the AH-I that allows for full autonomous flight capability (Figure 1). The platform provides over the horizon or beyond line of site functionality for surveillance, communications relay, re-supply, and other search related tasks (Boeing, 2016). The H-6U has a operates with a maximum ceiling of 20,000 feet and six hour endurance. Autonomous control is carried out through waypoint control from take-off to landing and reaches a maximum speed of 145 knots true airspeed. Navigation is executed either through a fixed land based station or sea based. The unique ability of the little bird is that the helicopter can be manned and flown by onboard pilots in addition to the platforms unmanned capability as determined by the mission type.

The little bird command link allowing beyond line of site operation utilizes the Ku-band Tactical Common Data Link specifically operated by the U.S. Military for sending secure data and streaming video links to ground stations from aerial platforms (Boeing, 2016). The Ku band used for for communication over the TCDL protocol is a primary method of satellite communications (Tech-FAQ, 2015). The Ku band is found within the 11.7 to 12.7 GHz and 14 to 14.5 GHz frequencies of the electromagnetic spectrum (Figure 2 and 3) for uplink and downlink communication. One of the advantages of the Ku band is that the communication frequency is not restricted by power, which can allow for a decrease in size of the receiving dishes (Tech-FAQ,2015). In addition, the Ku band uplink and downlink power can be increased further, decreasing dish size since the Tactical Common Data Link takes advantage of both directional and omnidirectional antennas to transmit and receive the Ku band signal (Skyware Technologies, 2015). The little bird is also STANAG 4586 compliant, which allows interoperability between other compliant tactical UAS systems amongst allied forces (Lockheed Martin, 2015).

A team is required for operation of the little bird consisting of the pilot, payload operator, and navigation/mission planner. Navigation is pre-planned prior to each mission utilizing waypoints however, changes can occur allowing for dynamic control input by the navigator and pilot. Managing missions based on predetermined flight paths determined by waypoints based on mission type, weather, and other interferences allows for more of a supervisory role by the team during flight to help reduce cognitive workload and stress. Most missions carried out by the platform involve preplanned flight paths for intelligence, surveillance, and reconnaissance. The ground control station is normally located at a fixed location, which can also be aboard a ship at sea (Figure 4).

Flight beyond the line of sight allows for greater ISR abilities but introduces numerous human factors issues. The greatest issue is situational awareness. Flying beyond the line of site restricts the platform operating team to rely on streaming video and flight telemetry data from the UAV to make decisions. Following the proper procedures for any and all emergency procedures is another critical element when flying BLOS. Lost link is a common issue with some UAV platforms that must be dealt with appropriately otherwise the outcome can be catastrophic, especially when flying over inhabited locations. The advantage when operating the little bird is that the platform has vertical take off and landing capability. VTOL allows for a more safely guided emergency landing in almost any location if the lost link procedures fail for any reason or if landing the vehicle in an emergency situation is required.

Each team member part of any unmanned aerial vehicle flying crew operating behind line of sight relies upon open communication, teamwork, and a pilot with strong leadership skills. The increased disconnect between crew and unmanned aircraft requires a higher level of crew resource management understanding, training, and commitment for safe flight operations in all environments when flying beyond line of sight.

References

Artes. (2015). ESPRIT - Artes Programme, Next Generation of Systems, Future Preparations. Retrieved from https://artes.esa.int/projects/esprit

Basu, P. Quora. Retrieved from https://www.quora.com/What-do-you-mean-by-C-band-extended-C-band-and-Ku-band-whats-the-difference-and-what-purpose-does-it-serve

Boeing. (2016). Unmanned Little Bird H-6U. Retrieved from http://www.boeing.com/defense/unmanned-little-bird-h-6u/#/feature-stories

Tech-FAQ. (2015). Ku Band. Retrieved from http://www.tech-faq.com/ku-band.html

Gardiner, G. (2013). Composites aid connectivity on commercial aircraft. Retrieved from http://www.compositesworld.com/articles/composites-aid-connectivity-on-commercial-aircraft

Lockheed Martin. (2015). STANAG 4586. Retrieved from http://www.lockheedmartin.com/us/products/cdl-systems/about-us/stanag-4586.html

Skyware Technologies. (2015). Ka vs. Ku – An Unbiased Review. Retrieved from http://www.skywaretechnologies.com/news/item/84-ka-vs-ku-an-unbiased-review

Unmanned GCS Human Factors Issues – Lockheed Martin mGCS

The research process for ground control stations was at first a bit challenging in finding specific details about each system for military applications. I discovered a good amount of information on the Lockheed Martin mobile ground control station which I feel will be more prevalent in the future due to the use of lower cost mini/small multi-rotor and fixed wing unmanned aircraft in both military and commercial applications. The mobile ground control station is optimized to be portable in all situations allowing for touch screen operation, and interface options with other laptops, tablets (Windows/Linux), or hand-held devices (Lockheed Martin, 2015). The system offers interoperability with numerous aircraft such as quad-copters, fixed wing, and other multi-rotor unmanned aircraft. Lockheed Martin is participating in the development of the NATO interoperability standard for UAV’s utilizing the STANAG4586 protocol (Lockheed Martin, 2016). The standard allows for commonality and the promotion of a protocol to help in the advancement of UAV interoperability. The smaller mobile system allows for quick and rapid deployment in the field with embedded touch screen, antenna, and power pack all in one unit (Lockheed Martin, 2013).

The hand held controller can act as a remote viewing terminal as well as the controls for the air vehicle. The mobile system was designed to be intuitive and simple as can be seen by the controller in Figure 1.

Figure 1. Adapted from http://www.lockheedmartin.com/us/products/cdl-systems/mgcs.html



The interactive map has been designed to help enhance situational awareness allowing for map toggle modes for viewing large-video/small map and small-video/large map options quickly and seamlessly. Setting waypoints, loiter points, and headings can be done by simply touching the desired point of interest. Flight modes include waypoint, fly by sensor, manual, loiter, launch, land, and return to home. Figure 3 and 4 show the interactive viewing map screen and a sample of the menu options.

Figure 3.  Adapted from http://www.lockheedmartin.com/us/products/cdl-systems/mgcs.html

Figure 4.  Adapted from http://www.lockheedmartin.com/us/products/cdl-systems/mgcs.html

The mobile GCS system was designed with simplicity in mind to allow the operator ease of operation. The disadvantages of a mobile ground control station are a reduction in sensory cues due to being in an outdoor environment versus indoors where distractions are minimized. The mobile hand-held controller, although convenient, only has visual display capability with little to no haptic or tactile feedback further reducing sensory cues and increasing the disconnect between operator and pilot. Audio and visual alarm cues might not be enough when an operator is controlling an air vehicle outdoors in more extreme environments. Some type of force feedback or vibration in addition to standard methods would be beneficial to ensure the operator is aware of specific flight conditions or issues. System warnings would include turbulence, weather changes, severe banking, and encroachment of other aircraft.

The mobile GCS could also suffer from viewing difficulties without the proper sun visor, shade, or other type of protection. This issue an easily be resolved but needs serious consideration based on the usage environment.

Issues with the human-machine interface include the user screen interface being slightly “busy” for the size of the hand-held controller. The interoperability of the GCS system is a major advantage however; the software should recognize the controller and remote terminal type and adjust the user interface based on screen size and resolution. The held-held controller is field friendly but the smaller screen size can be challenging visually, impact cognitive workload, and workload management (Hobbs, Alan, 2013). Also the smaller screen size can allow for “fat fingering” of a command. A fix for this would be either double tapping commands or a confirmation of specific commands to eliminate incorrect selections.

Lastly, when designing a mobile handheld GCS that only utilizes a single screen the human factors engineering processes must be firmly integrated to take into account all human machine interface concerns. The number of onscreen options, spacing, color schemes, picture in picture, joystick placement to reduce fatigue, and safety warnings that are audible and visual.




References

Hobbs, Alan. (2013). Human Factor Challenges of Remotely Piloted Aircraft. Retrieved from http://human-factors.arc.nasa.gov/publications/Hobbs_EAAP.pdf

Lockheed Martin. (2015). Mobile Ground Control Station. Retrieved from http://www.lockheedmartin.com/us/products/cdl-systems/mgcs.html

Lockheed Martin. (2016). mGCS Civil, Ground Control Operator Software for Commercial Applications. Retrieved from http://www.lockheedmartin.com/content/dam/lockheed/data/ms2/documents/cdl-systems/mGCS-Commercial-brochure.pdf

Lockheed Martin. (2016). mGCS, Mini and Small UAV Ground Control Operator Software. Retrieved from http://www.lockheedmartin.com/content/dam/lockheed/data/ms2/documents/cdl-systems/CDL_mGCS_Datasheet_080613.pdf

Lockheed Martin (2013). mGCS Capabilities Guide, Mini and Small UAV Ground Control Operator Software. Retrieved from http://www.lockheedmartin.com/content/dam/lockheed/data/ms2/documents/cdl-systems/mGCSCapabilitiesGuide-2013.pdf