Autopilot and Flight Director[PDF]
- 1 Introduction
- 2 Control Panel
- 3 Flight Director (F/D)
- 4 Autopilot (A/P)
- 5 Auto-speed management
- 6 Conclusion
- 7 See also
- 8 Reference
- 9 Author
In normal situations, computers have always been more precise than human pilots and their ability to determine rapidly the results of any necessary calculations have made them irreplaceable in our cockpits.
Since any automated systems require input parameters, your autopilot and the flight director will need such values as target attitude, speed, altitude, heading and so on.
Type of control panel
- the current pitch is maintained (PITCH)
- the wings are leveled (ROLL)
- pitch angle
- heading or track
On some autopilot systems, the pilot may be able to select the target altitude. The aircraft will reach this altitude by maintaining a specific pitch angle either selected by the pilot or given at autopilot engagement. Upon reaching the target altitude, aircraft shall establish a level flight.
Finally, if the aircraft is fitted with a heading/track selector coupled with a HSI for example, the pilot may select a specific course to be kept by the autopilot.
Flight Mode Annunciator
Flight Director (F/D)
The flight director is a display that appears above the attitude indicator (ADI, eADI or PFD for example) in order to indicate the position in which the pilot should bring his aircraft in order to accurately follow the flightpath he intended to fly using the flight modes he selected on his control panel.
Flight Path Vector
Regulations, rules and usage
There are not many regulations concerning the flight director.
- inside airspaces that require a PBN specification (RNAV10, RNAV5, RNAV/RNP1). The flight director must be switched on when there is no CDI to display the deviation of the route being tracked. Typically it happens in “MAP” mode.
- RNP AR procedures due to RF legs that cannot be flown correctly without instant computations.
- Raw data approaches for training purposes
- Visual approaches
The autopilot was made to relieve the pilot from hand flying on long flights. Then, with the increase in precision, it was also part of the certification process of high-precision approaches such as ILS CAT III.
Regulations, rules and usage
- Certification of single-pilot aircraft
- Operations in RVSM airspace
- ILS CAT I/II/III regulations
Certification of single-pilot aircraft
Some aircraft that are certified for single-pilot operations require that the autopilot must be operative in order to perform the flight. That may be due to the complexity to operate some aircraft systems while being able to fly the aircraft manually due to an autopilot failure.
Operations in RVSM airspace
ILS CAT I/II/III regulations
- Cat I: When the RVR is below 800m, autopilot must be engaged in single-pilot operations.
- Cat II: Autopilot must be switched on for the entire duration of the approach until DH.
- Cat III: This category finishes with an autoland which requires the autopilot to be engaged.
- Most autopilots have a limitation concerning its engagement:
- It must be engaged above a specified height for safety reasons.
- It must be engaged after a specified time following takeoff
- Always know your FMA when flying with the autopilot.
- Autopilot should never be engaged while applying a force on the flight controller.
- Autopilot should be engaged to decrease the workload when the aircraft is in a stable situation.
- Subsequently to a failure, if the autopilot did not disengage automatically and that the failure does not require doing so immediately: do not disconnect the autopilot intentionally.
An aircraft is supposed to:
- Climb using a fixed specific climb thrust
- Descend at fixed idle thrust
It seems difficult to design an aircraft without autopilot or autothrottle since it helped so much to increase the safety records of the last decades. However, it still represents a danger given the fact that the human understanding or the human trust in these systems can be too high and lead to accidents. These particular accidents have led to the creation of a specific branch in the human factor.
Whatsoever, real airline recurrent simulator trainings are organized as to maintain the manual flying skills of pilots whenever the automation fails or is not adapted to the situation.
- VID 150259 - Creation
- VID 450012 - Wiki Integration
DATE OF SUBMISSION
- 20:16, 19 January 2019
- This documentation is copyrighted as part of the intellectual property of the International Virtual Aviation Organisation.
- The content of this documentation is intended for aviation simulation only and must not be used for real aviation operations.