MQ-9
BLOS
Many unmanned aerial systems (UAS) flying
today have such a high endurance rate that capable distances far exceed
communications distances. The MQ-9 Reaper is once such UAS. The MQ-9 flies off
of a communications data link provided that the aircraft has a viable link from
the ground station and global positioning satellites (GPS) overhead. Like many
military UAS, the Reaper operates in the encrypted Ku-band at the 12-18 GHz
range (Marshall, Barnhart, Shappee, & Most, 2016). Launch and recovery
operations of the Predator are conducted via line of sight (LOS) and then
transferred to beyond line of sight (BLOS) once the aircraft is airborne
(Marshall et al., 2016). MQ-9 remote command and control through BLOS links via
satellite communications (SATCOM) allows operators to not be co-located with
the launch and recovery team downrange (USAF, 2015). Positive hand off of the Reaper from the
launch and recovery team to the mission control team is a delicate process and
procedures are followed to ensure a secure hand-off.
Advantages
and Disadvantages
Line of sight
(LOS) operations can only be accomplished in so far as the radio frequencies
can reach the aircraft and back to the ground station. Once a LOS UAS passes
over the curvature of the Earth and the radio frequency diminishes, operations
become impossible. However, LOS operations for UAS are considered more reliable
since they are conducted using radio frequencies. BLOS can also be
unpredictable and lost link situations happen often with older UAS equipment.
BLOS operations can be very effective when flying at high altitudes or beyond
the horizon. Most military UAS are now upgrading their datalink technology to
operate on BLOS communication 100% of the time. BLOS communications for UAS has
the possibility to be better than LOS.
Human
Factors Issues
A huge disadvantage of UAS switching
from LOS to BLOS during operations is the fact that due to the many relays and
systems commands must travel though, communications with the UAS can be
interrupted or delayed (Marshall et al., 2016). This interruption or delay can
lead to the pilot’s visual displays being impaired and therefore losing full
situation awareness of the aircraft’s position. The effects of this sensory
isolation cannot be overstated given that human beings are used to being part
of the action. Mental workloads are already at a heightened states when
operating a UAS and the sudden drop off of visual cues could lead to diminished
reaction times by the operator. As technology advances, switching from LOS to
BLOS operations will have limited to no affect at all on the operators ability
to fly the aircraft.
Commercial
Applications
Today, the United States regulates beyond line
of sight operations for most all UAS. These regulations prevent the full
exploitation of the applications associated with BLOS (Marshall et al., 2016). In
2015, the Federal Aviation Administration (FAA) conducted tests on commercial
UAS BLOS operations. One of the big roadblocks for UAS to enter the national
airspace systems (NAS) is the unreliability of communications links. Many
companies seeking to use UAS for large scale agriculture surveying or package
delivery are restricted from doing so by law (UAS Vision, 2015). BLOS for sUAS
like the Precision Hawk could help with sense and avoid problems with manned
aircraft and allow it to take automatic action to avoid aircraft or land if
needed (UAS Vision, 2015).
References
Marshall,
D.M., Barnhart, R.K., Shappee, E., & Most, M.T. (2016). Introduction to Unmanned Aircraft Systems, Second Edition. Boca
Raton: CRC Press. Retrieved from https://ebookcentral.proquest.com/lib/erau/detail.action?docID=4710295
United
States Air Force. (2015). MQ-9 Reaper
Fact Sheet. Retrieved from http://www.creech.af. mil/About-Us /Fact-Sheets/Display/Article/669890/mq-9-reaper-fact-sheet/
UAS
Vision. (2015). FAA will test drone’s
ability to fly BLOS. Retrieved from http://www.uasvision.com/2015/11/18/faa-will-test-drones-ability-to-fly-blos/
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