UAS Beyond Line of Sight Operations

       Beyond line of sight (BLOS) operations can present a number of problems to an unmanned aerial system (UAS) operator that is not encountered when operating line of sight (LOS).  However, despite these problems, they can also present a number advantages.  From a technical aspect a number of command and communications problems arise when a UAS system is operated BLOS due to environmental conditions.  It is up the control system on board to take over in the event of a lost link situation, however, when not in a lost link situation, it is up the operator to provide full control or supervisory control.  While in control, a number of human factor issues can come in to play.

In 2013, a study was conducted by S. Giese, using 15 years of U.S. Air Force (USAF) data consisting primarily of “Predator” series statistics (Including MQ-1A and MQ-9). The study noted, “high in-service mishap rates for the RQ-1 Predator, RQ-5 Hunter and RQ-2 Pioneer of 32, 55 and 334 mishaps per 100,000 flight hours respectively,” (Giese, 2013).  This is high when compared the equivalent safety level of civil aviation of 1 in 100,000 hours, (Giese, 2013).  Aside, from these statistics, mishaps were broke down by times of error, “The highest percentage of human-related mishaps was connected to skill-based errors. As [15] had also found, most common in the present study were procedural errors, followed by checklist errors, inadvertent operation, overcontrol/undercontrol, and finally breakdown in visual scan… Skills have to be learned and practiced, thus the results suggest deficiencies in initial and recurring crew training. They could also imply that pilots recruited to control UASs are not ideal for the task, implicating issues with recruitment and selection processes,” (Giese, 2013).

            UAS are generally operated by aviators who at some point have flown a manned aircraft of some sort.  However, not all UAS developers are not traditional aircraft manufactures, “UASs are mainly developed by entities other than the traditional aircraft manufacturers and are not flown conventionally and thus do not necessarily follow the same design rules as manned aircraft. Therefore, GCSs can be quite dissimilar to manned aircraft cockpits, and in fact, the only comparable interface is that of Predator [15]. However, the Predator GCS has not changed fundamentally for 20 years,” (Geise, 2013).

“The results of this study support previous findings where the presence of perceptual and cognitive failures combined with perceptual and skill-based errors suggested pilot Situation Awareness (SA) had been compromised. Cognitive failures were mainly due to inattention, channelized attention and confusion. Misperception of operational conditions (such as altitude and speed) and expectancy were the most common perceptual failures. Hence primarily, the crew’s ability to make observations about the environment in time and space is affected,” (Giese, 2013).

With all of this in mind, it can be interpolated that ground control station (GCS) layouts when flying BLOS does not provide an aviator with data in a familiar format.  Additionally, a pilot can longer rely on tactile senses, which are sometimes referred to as the “seat of the pants” feeling that further reduces situational awareness (SA).  This is not to say that BLOS flights are dangerous due to a loss of SA, but that due to a reduction of SA other cues must be given to the operator in the GCS.  BLOS flights can in the private sector could provide a large market for delivery, transportation, surveying, traffic control/reports.

References

Giese, S., Carr, D., & Chahl, J. (2013). Implications for unmanned systems research of military UAV mishap statistics. Paper presented at the 1191-1196. doi:10.1109/IVS.2013.6629628. Retrieved from http://ieeexplore.ieee.org.ezproxy.libproxy.db.erau.edu/stamp/stamp.jsp?tp=&arnumber=6629628

UAS Integration in the NAS

       “FAA, collaborating with other federal agencies and the aviation industry, is implementing NextGen, an advanced technology air-traffic management system that FAA anticipates will replace the current ground-radar-based system,” (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  FAA’s Next Generation Air Transportation System (NextGen) consists of multiple programs including, Automatic Dependent Surveillance-Broadcast (ADS-B), Collaborative Air Traffic Management Technologies (CATMT), Data Communications (Data Comm), National Airspace System Voice System (NVS), NextGen Weather, and System Wide Information Management (SWIM), (NextGen Programs, 2016).  Through 2018, the NextGen program is expected to cost $18 billion, (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  Through the implementation of multiple programs the NextGen program will, “enhance safety, increase capacity, and reduce congestion in the national airspace system,” (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  While the NextGen program is made to make the National Airspace (NAS) more efficient, it could benefit remotely piloted vehicles (RPV) which are better known as unmanned aerial vehicles (UAVs).  “By determining how UAS flight operations and protocols may be different than those of traditional manned aircraft, informed decisions can be made concerning the data and interfaces required to accommodate routine UAS operations by NextGen automation systems, ultimately leading to safer and more efficient integration of UAS into non-segregated civil airspace,” (Paczan, 2012).

“ADS-B makes use of GPS technology to determine and share precise aircraft location information, and streams additional flight information to the cockpits of properly equipped aircraft,” (NextGen Programs, 2016).  Unmanned aircraft equipped with ADS-B will be able to share its location with aircraft and flight following services.  This will be helpful in the event of a lost link where the unmanned aircraft operator is unable to communicate commands to the unmanned vehicle.  When there is a lost link the operator is unable to continue to see and avoid, the unmanned systems typically have a failsafe in the event of a lost link, but with ADS-B the precise location of the unmanned system will be reported, enabling air traffic control to route aircraft around the lost link aircraft.

Data Comm, “will enable controllers to send digital instructions and clearances to pilots. Precise visual messages that appear on a cockpit display can interact with an aircraft's flight computer. Offering reduced opportunities for error, Data Comm will supplant voice communications as the primary means of communication between controllers and flight crews,” (NextGen Programs, 2016).  Data Comm could raise issues with unmanned systems, especially with plans to have it replace voice communications.  The Data Comm would have to be sent to the unmanned vehicle and then the instructions would be relayed to the ground control station (GCS).  In the event of a lost link where the unmanned vehicle and GCS are no longer able to communicate, this would mean that the Data Comm would no longer be able to be received by the operator.  This is no different than how voice communications with current unmanned systems currently work.  Currently Data Link plans to use digital radio frequencies, however, in theory, it could be connected to the internet, and could allow the operator to inform flight following services of a lost link.

“Once all planned programs are in place, FAA expects NextGen to deliver $134 billion in direct airline, industry, and passenger benefits (passenger value of time and carbon dioxide emissions) through 2030,” (NextGen Programs, 2016).  While, there is no deliberately stated goal of helping to integrate RPVs or UAVs through the implementation of the NextGen program, the unmanned industry can benefit from the integration of the NextGen systems and programs.

References

NextGen Programs. (2016 Apr 6). NextGen, Federal Aviation Administration. Retrieved from https://www.faa.gov/nextgen/programs/

Paczan, N. M., Cooper, J., & Zakrzewski, E. (2012). Integrating unmanned aircraft into NextGen automation systems. Paper presented at the 8C3-1-8C3-9. doi:10.1109/DASC.2012.6382440

United States. Federal Aviation Administration, & United States. Government Accountability Office. (2013). NextGen air transportation system: FAA has made some progress in midterm implementation, but ongoing challenges limit expected benefits : Report to congressional requesters. Washington, D.C.: U.S. Govt. Accountability Office. Retrieved from http://www.gao.gov/assets/660/653628.txt

UAS Integration in the NAS

            “FAA, collaborating with other federal agencies and the aviation industry, is implementing NextGen, an advanced technology air-traffic management system that FAA anticipates will replace the current ground-radar-based system,” (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  FAA’s Next Generation Air Transportation System (NextGen) consists of multiple programs including, Automatic Dependent Surveillance-Broadcast (ADS-B), Collaborative Air Traffic Management Technologies (CATMT), Data Communications (Data Comm), National Airspace System Voice System (NVS), NextGen Weather, and System Wide Information Management (SWIM), (NextGen Programs, 2016).  Through 2018, the NextGen program is expected to cost $18 billion, (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  Through the implementation of multiple programs the NextGen program will, “enhance safety, increase capacity, and reduce congestion in the national airspace system,” (United States. Federal Aviation Administration, & United States. Government Accountability Office, 2013).  While the NextGen program is made to make the National Airspace (NAS) more efficient, it could benefit remotely piloted vehicles (RPV) which are better known as unmanned aerial vehicles (UAVs).  “By determining how UAS flight operations and protocols may be different than those of traditional manned aircraft, informed decisions can be made concerning the data and interfaces required to accommodate routine UAS operations by NextGen automation systems, ultimately leading to safer and more efficient integration of UAS into non-segregated civil airspace,” (Paczan, 2012).

“ADS-B makes use of GPS technology to determine and share precise aircraft location information, and streams additional flight information to the cockpits of properly equipped aircraft,” (NextGen Programs, 2016).  Unmanned aircraft equipped with ADS-B will be able to share its location with aircraft and flight following services.  This will be helpful in the event of a lost link where the unmanned aircraft operator is unable to communicate commands to the unmanned vehicle.  When there is a lost link the operator is unable to continue to see and avoid, the unmanned systems typically have a failsafe in the event of a lost link, but with ADS-B the precise location of the unmanned system will be reported, enabling air traffic control to route aircraft around the lost link aircraft.

Data Comm, “will enable controllers to send digital instructions and clearances to pilots. Precise visual messages that appear on a cockpit display can interact with an aircraft's flight computer. Offering reduced opportunities for error, Data Comm will supplant voice communications as the primary means of communication between controllers and flight crews,” (NextGen Programs, 2016).  Data Comm could raise issues with unmanned systems, especially with plans to have it replace voice communications.  The Data Comm would have to be sent to the unmanned vehicle and then the instructions would be relayed to the ground control station (GCS).  In the event of a lost link where the unmanned vehicle and GCS are no longer able to communicate, this would mean that the Data Comm would no longer be able to be received by the operator.  This is no different than how voice communications with current unmanned systems currently work.  Currently Data Link plans to use digital radio frequencies, however, in theory, it could be connected to the internet, and could allow the operator to inform flight following services of a lost link.

“Once all planned programs are in place, FAA expects NextGen to deliver $134 billion in direct airline, industry, and passenger benefits (passenger value of time and carbon dioxide emissions) through 2030,” (NextGen Programs, 2016).  While, there is no deliberately stated goal of helping to integrate RPVs or UAVs through the implementation of the NextGen program, the unmanned industry can benefit from the integration of the NextGen systems and programs.

References

NextGen Programs. (2016 Apr 6). NextGen, Federal Aviation Administration. Retrieved from https://www.faa.gov/nextgen/programs/

Paczan, N. M., Cooper, J., & Zakrzewski, E. (2012). Integrating unmanned aircraft into NextGen automation systems. Paper presented at the 8C3-1-8C3-9. doi:10.1109/DASC.2012.6382440

United States. Federal Aviation Administration, & United States. Government Accountability Office. (2013). NextGen air transportation system: FAA has made some progress in midterm implementation, but ongoing challenges limit expected benefits : Report to congressional requesters. Washington, D.C.: U.S. Govt. Accountability Office. Retrieved from http://www.gao.gov/assets/660/653628.txt

UAS GCS Human Factors Issue

               In this research activity, the Walkera Runner 250 Advance ground control station (GCS) will be examined in depth.  The Walkera Runner 250 Advance is a 250mm quadcopter and is what is known as a First Person View (FPV) Racer.  It is manufactured by Chinese manufacture Wakera and is 250mm diagonally from motor to motor.  It transmits video via 5.8 GHz, is equipped with dual GPS module, and is capable of acrobatic flight, (Walkera Runner 250(R) Quick Start Guide, 2015).

                The Runner 250 Advance comes with an optional on screen display (OSD) for users that want to fly in a mode called FPV, where a spotter is used to keep the aircraft in line of sight (LOS) and the operator fly’s by looking at the screen.  The video is transmitted via 5.8 GHz and is only a 2 dimensional image, because of this the OSD is key when learning to fly FPV.

                Companies that manufacture these FPV Racer quadcopters are typically not aviation companies.  Thus, when someone that comes from the aviation community and tries to fly one, they can find the information provided by the OSD confusing.  Figure [1], comes from Walkera Runner 250(R) Quick Start Guide.  Instantly one can notice there is a plethora of information displayed.  Arguably there is too much information, and some information is not well placed.  For example, an aviator will notice the horizontal distance is in the top right corner under the time, however, on modern manned aircraft, distance measuring equipment (DME) is usually situated above and to the left of a compass card.  While DME and horizontal distance to the operator are different, they provide a similar function, because as a FPV flight is coming to an end, the user will want to fly back to their position, thus giving a similar use to DME readout.  Additionally, the Walkera OSD places the vertical speed indicator (VSI) above the horizontal speed indicator, rather than above the altitude read out.  Because of this, the user must shift their eyes from the right side of the screen to read the altitude, then to the opposite side to read the VSI.  If the two above mentioned items Distance and VSI were shifted this would give a similar readout that is found in most modern manned aircraft.  Additionally, latitude and longitude are listed on the bottom of the screen, this is a function of the GPS on the Runner 250 Advance.  The Runner 250 Advance is a “racer” and this is superfluous information that does not provide the operator with any additional situational awareness. 

Lastly, a sometimes controversial subject of units comes to light.  All units are in metric units of measure, this may not be an issue for most and can be adapted easily.  However, FPV racers typically fly close to the ground, and if the altitude readout were in feet, then the use of the OSD could facilitate a closer flight to the ground. These numbers could also read out in fractions of a meter but will ultimately add more digits to read an altitude, for this reason feet should be the accepted measure of altitude.

FIGURE [1]. Courtesy of Wakera Runner 250(R) Quick Start Guide.

                Overall, the Walkera Runner 250 Advance offers an entry level FPV Racer with many features, however, like most other sUAS they are not made by aviation companies and place information in places that are not intuitive the aviator.  Similarly to manned aviation, there are not standards in where information is placed but lots of research has been conducted in the realm of human factors and making sure information is easily accessible to the aviator.  The UAS community should learn from the manned community where there is not standard in information placement and units of measurements, and standardization should be adopted to make transitions from manned aircraft and between unmanned aircraft easier, additionally, this will make transitions from one manufacture to the other easier as well.

Reference

Walkera Runner 250(R) Quick Start Guide. (2015 Oct 20). Walkera.