The auto-land system enables an aircraft to automatically carry out all required maneuvers during the approach and the landing phase of a flight. This function is carried out by the autopilot system.
Auto-land systems were introduced in 1968 and represented a remarkable achievement in the aviation industry on a Caravelle AIR INTER aircraft (Airbus, 2001). The purpose of auto-land systems is to allow operations in poor meteorological conditions that hinder the flight crew visual perception and thus achieving economical value and remarkable safety to the airline industry under such challenging conditions (Airbus, 2001).
On a manned aircraft like an Airbus A320, the auto-land function requires a number of systems to be operational, like the autopilot function, FMGS (Flight Management and Guidance System), auto-thrust, nose-wheel steering, and auto-breaks. The availability of all of these systems will allow fully automated landing, rollout on centerline, and braking of the airplane on an adequately equipped runway without any visual reference or pilot interference (Airbus, 2001).
Such approach is classified under CAT II or CAT III-A, B, and C. CAT II requires the acquisitions of minimal visual cues by the flight crew to assure the aircraft position prior to landing and maybe carried out with a only one auto-pilot, one FMGS, and without auto-thrust, nose-wheel steering, and auto-brake following the concept of a fail passive approach. CAT III-C requires all systems to be operative including a dual autopilot function to assure the safety of landing, even if some systems fail during the most critical phase of the landing following the concept of a fail operational approach. ICOA defines CAT III-C as “a precision approach and landing with no decision height and no runway visual range limitations” (Airbus, 2001).
The execution of auto-land incurs higher requirements compared to other approaches; adequate aircraft equipment, adequate runway landing ILS (Instrument Landing System) facility, adequate flight crew training, and appropriate certification of the operator by the state. Other restrictions include lower wind criteria, lower runway elevation, shallower approach gradient, and lower maximum landing weight compared to manual landings (Airbus, 2001).
The UAS (Unmanned Aerial Systems) readily exclude an onboard pilot. An approach and landing can be remotely piloted from a distant post utilizing line-of-sight or instrument readings presented on the control console. The dislocation of the pilot from the air vehicle removes most of the salient visual cues compared to landing a manned aircraft. This makes the introduction of auto-land and auto-takeoff systems for UAS a reasonable method for routine operations. UAS widely differ from manned aircraft on flying characteristics and performance aspects. Another difference is the operational theater may include unpaved runway strips and unpublished takeoff and landing procedures.
BAE systems developed an experimental UAS for testing FCS (Flight Control Systems) that will enable small UAS to carry out automated takeoff and landing. The autopilot system was installed on a wing type propelled aircraft for demonstration purposes. The navigation during takeoff and landing was carried out using a fusion of sensors like GPS receivers, laser altimeters, clinometers, and IMU (Inertial Measurement Unit). The landing and takeoff maneuvers required robust control inputs to precisely guide the aircraft on the required vertical and horizontal trajectories in the presence of rapidly varying winds. The basic navigation relies on waypoint to waypoint sequencing (Riseborough, 2004).
Airbus (2001). Getting to Grips with CAT II/ CAT III Operations. Retrieved from skybrary.aero/bookshelf/books/1480.pdf
Riseborough, P. (2004, July). Automatic take-off and landing control for small UAVs. In Control Conference, 2004. 5th Asian (Vol. 2, pp. 754-762). IEEE.
Auto-land systems were introduced in 1968 and represented a remarkable achievement in the aviation industry on a Caravelle AIR INTER aircraft (Airbus, 2001). The purpose of auto-land systems is to allow operations in poor meteorological conditions that hinder the flight crew visual perception and thus achieving economical value and remarkable safety to the airline industry under such challenging conditions (Airbus, 2001).
On a manned aircraft like an Airbus A320, the auto-land function requires a number of systems to be operational, like the autopilot function, FMGS (Flight Management and Guidance System), auto-thrust, nose-wheel steering, and auto-breaks. The availability of all of these systems will allow fully automated landing, rollout on centerline, and braking of the airplane on an adequately equipped runway without any visual reference or pilot interference (Airbus, 2001).
Such approach is classified under CAT II or CAT III-A, B, and C. CAT II requires the acquisitions of minimal visual cues by the flight crew to assure the aircraft position prior to landing and maybe carried out with a only one auto-pilot, one FMGS, and without auto-thrust, nose-wheel steering, and auto-brake following the concept of a fail passive approach. CAT III-C requires all systems to be operative including a dual autopilot function to assure the safety of landing, even if some systems fail during the most critical phase of the landing following the concept of a fail operational approach. ICOA defines CAT III-C as “a precision approach and landing with no decision height and no runway visual range limitations” (Airbus, 2001).
The execution of auto-land incurs higher requirements compared to other approaches; adequate aircraft equipment, adequate runway landing ILS (Instrument Landing System) facility, adequate flight crew training, and appropriate certification of the operator by the state. Other restrictions include lower wind criteria, lower runway elevation, shallower approach gradient, and lower maximum landing weight compared to manual landings (Airbus, 2001).
The UAS (Unmanned Aerial Systems) readily exclude an onboard pilot. An approach and landing can be remotely piloted from a distant post utilizing line-of-sight or instrument readings presented on the control console. The dislocation of the pilot from the air vehicle removes most of the salient visual cues compared to landing a manned aircraft. This makes the introduction of auto-land and auto-takeoff systems for UAS a reasonable method for routine operations. UAS widely differ from manned aircraft on flying characteristics and performance aspects. Another difference is the operational theater may include unpaved runway strips and unpublished takeoff and landing procedures.
BAE systems developed an experimental UAS for testing FCS (Flight Control Systems) that will enable small UAS to carry out automated takeoff and landing. The autopilot system was installed on a wing type propelled aircraft for demonstration purposes. The navigation during takeoff and landing was carried out using a fusion of sensors like GPS receivers, laser altimeters, clinometers, and IMU (Inertial Measurement Unit). The landing and takeoff maneuvers required robust control inputs to precisely guide the aircraft on the required vertical and horizontal trajectories in the presence of rapidly varying winds. The basic navigation relies on waypoint to waypoint sequencing (Riseborough, 2004).
References
Airbus (2001). Getting to Grips with CAT II/ CAT III Operations. Retrieved from skybrary.aero/bookshelf/books/1480.pdf
Riseborough, P. (2004, July). Automatic take-off and landing control for small UAVs. In Control Conference, 2004. 5th Asian (Vol. 2, pp. 754-762). IEEE.
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