Introduction
In
1903, the first controllable aircraft was made of fabric and the flight control
surfaces were controlled by cables. As technology advances, aircraft systems
are getting more complex. Today, commercial aircraft can climb up to 41,000
feet; cruise at 950 km/ h; fly between continents within few hours; and bring
passengers safely from one point to another. Interestingly, air transport is
still the safest mode of transport compared to the land and sea transports. One
of the reasons is the emphasis of ‘safe ‘culture in aviation industries from
the human factors perspective. In view of this, the concept of workload is
important because it is central to an understanding of pilot performance
leading to efficient operation of the aviation system (Orlady & Orlady, 2015)
Aircraft
Automation
According to authors, the definition
of workload involves several variables. Excessive workload leads to experiences
such as difficulty, discomfort and anxiety. In order to reduce pilot’s workload,
one of the solutions is automation of aircraft systems. There are few prominent
automation systems such as autopilots, auto-throttles and anti-skid, which are
widely used during critical flight phases such as takeoff and landing. In fact,
to accommodate two-person crew operation, aircraft systems and subsystems have
been simplified and automated gradually. These systems include aircraft
electrical; hydraulic; pneumatic and fuel systems.
Autopilot
of B787
Boeing B787 is one of the most
advanced commercial aircraft to date. The selling points are lower operating
costs, higher revenue potential and visionary designs such as electric-system
architecture; composite primary structure; passenger pleasing features;
advanced aerodynamics; optimized flight deck and modern efficient engines (Boeing, 2016) . Boeing B787
autopilot system is called auto flight function, which is an application
resides in flight control module. The auto flight function (AFF) operates on
the ground and in flight. The function calculates commands for flight phases
such as takeoff; climb; cruise; descent; approach, auto land, rollout and
go-around (Boeing, 2014) .
Level
of Autonomy during B787 Takeoff and Landing
During aircraft take-off phase, auto
flight function computes airspeed, pitch angle and thrust limits and displays
them on primary flight display and Engine Indication and Crew Alerting System
(EICAS). Still, pilot is required to control throttle lever for engine thrust
and control column to pitch aircraft during take-off phase. According to Barnhart,
Hottman, Marshall & Shappee (2016), they classified auto flight function
during take-off as low level autonomy. The pilot interaction is the main
component for final execution.
During landing phase, Boeing B787 is
capable of full auto land, also known as LAND 3 capability with high degree of
autonomy. The system performs redundancy, self-test and also monitors various
systems such as ground based Instrument Landing System (ILS) and CAT III
airborne and ground equipment. When combined with a properly trained flight
crew, LAND 3 allows landing approach to be conducted to visibility as low as
zero. The CAT III auto land is widely used in Europe during winter when heavy
snow and frequent fog reduced pilot’s visibility.
Level
of Autonomy during Predator Takeoff and Landing
Predator
follows a conventional launch sequence from a semi-prepared surface under
direct line-of-sight control. Pilot computes and inputs weight of aircraft and
payload, takeoff speed and length of runway into the system. The take-off and landing length is typically
2,000ft. The mission can be controlled through line-of-site data links or
through Ku-band satellite links to produce continuous video (Airforce-Technology.Com,
2016)
with mid-level of autonomy. The definition of mid-level autonomy refers to 50%
- 50% control ratio between pilot and autopilot system. The pilot provides
Predator with missions and goals. When ready, pilot must confirm and approve the
execution to be performed by Predator.
Conclusion
The
development of automation raises some concerns. From the human factors
perspective, does it compromise pilot’s ability to monitor aircraft critical
systems effectively? More crucially, how to determine the degree of automation
before safety is compromised. Do we allow given systems to shut off
automatically or changed without notifying pilot? In view of these concerns, it
is important that the automatic operation is accompanied by appropriate
feedback and immediate notification to alert pilots with visual, audio and
tactile sensory getters (Orlady & Orlady, 2015) .
Reference
Airforce-Technology.Com.
(2016, July 9th). Predator RQ-1 / MQ-1 / MQ-9 Reaper UAV, United States of
America. Retrieved from http://www.airforce-technology.com/projects/predator-uav/
Barnhart, R.
K., Hottman, S. B., Marshall, D. M., & Shappee, E. (2016). Introduction to
UAS. Baton Rouge: CRD
Boeing.
(2014). Electro-Avionics Systems 2. Singapore: SIAEC.
Boeing.
(2016, july 9th). 787 Dreamliner Family. Retrieved from
http://www.boeing.com/commercial/787/#/overview
Orlady, H.
W., & Orlady, L. M. (2015). Human Factors in Multi-Crew Flight
Operations. Surrey: Ashgate.
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