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