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b. ACs. An electronic copy of the following ACs can be downloaded from the internet at http://www.faa.gov/regulations_policies/advisory_circulars/ or our Regulatory and Guidance Library (RGL) at http://rgl.faa.gov/ .
Number Title AC 20-115B RTCA, Inc., Document RTCA/DO 178B [Radio Technical Commission for Aeronautics] AC 20-138B Airworthiness Approval of Positioning and Navigation Systems AC 20-152 Design Assurance Guidance for Airborne Electronic Hardware RTCA/DO 254 AC 25-7C Flight Test Guide for Certification of Transport Category Airplanes AC 25-11A Transport Category Airplane Electronic Display Systems AC 25-12 Airworthiness Criteria for the Approval of Airborne Windshear Warning Systems in Transport Category Airplanes AC 25.672-1 Active Flight Controls AC 25.1309-1A System Design and Analysis AC 25.1419-1A Certification of Transport Category Airplanes for Flight in Icing Conditions AC 25.1581-1 Change 1 Airplane Flight Manual AC 120-28D Criteria for Approval of Category III Weather Minima for Takeoff, Landing, and Rollout AC 120-29A Criteria for Approving Category 1 and Category II Landing Minima for FAR 121 Operators AC 120-41 Criteria for Operational Approval of Airborne Windshear Alerting and Flight Guidance Systems
Note: This table repr esents the latest version of each AC at the time of publication. These individual ACs may be updated in the future, such that this table may reference a specific version of an AC that has been superseded. The latest version of each AC should always be used, even though this document may reference a previous version of an AC.
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c. Related Industry Standards. The following documents are available from the Society of Automotive Engineers (SAE). These documents can be obtained from the Society of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, Pennsylvania, 15096 electronically from the SAE International website, http://www.sae.org/.
Number Title SAE ARP5366 Autopilot, Flight Director and Autothrust Systems SAE ARP4754 Certification Considerations for Highly Integrated or Complex Aircraft Systems SAE ARP4761 Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment SAE ARP5288 Transport Category Airplane Head Up Display Systems SAE AS8055 Minimum Performance Standards for Airborne Head Up Display
The following docum ents are available from the RTCA, Inc. These documents can be purchased by mail from the RTCA Inc., 1150 18th Street NW, Suite 910, Washington, DC 20036; by fax, after completing the Document Order Form and faxing to 202-833- 9434; or electronically from the RTCA online store at: http://www.rtca.org/onlinecart/.
Number Title RTCA DO-178B/
EUROCAE ED-12B Software Considerations in Airborne Systems and Equipment Certification RTCA DO-160E/
EUROCAE ED–14D Environmental Conditions and Test Procedures for Airborne Equipment RTCA DO-254/
EUROCAE ED-80 Design Assurance Guidance for Airborne Electronic Hardware
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d. FAA Documents. An electronic copy of the following FAA document can be downloaded from the Internet at http://www.faa.gov/aircraft/air_cert/design_approvals/csta/publications/ .
Title Federal Aviation Administration Human Factors Team Report on: The Interfaces Between Flight Crews and Modern Flight Deck Systems – Jun 18, 1996
An electronic copy of the following FAA Order can be downloaded from the Internet at http://rgl.faa.gov/. A paper copy may be ordered from the U.S. Department of Transportation, Subsequent Distribution Office, M-30, Ardmore East Business Center, 3341 Q 75th Avenue, Landover, MD 20795.
Number Title FAA Order 8260.3 United States Standard for Terminal Instrument Procedures
John Piccola Acting Manager, Transport Airp lane Directorate Aircraft Certification Service
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CONTENTS
Paragraph Page
Chapter 1. Background
11. General 13
a. Advisory Circular (AC) 25.1329-1A 13
b. Scope 13
12. Evolution of Flight Guidance Systems (FGS) 13
a. Complexity 13
b. Guidance Considerations 13 13 – 16. [RESERVED] 13
Chapter 2. Overview of Flight Guidance Systems (FGS)
17. Purpose of FGS 15
18. FGS Components 15
a. Included in Definition 15
b. Excluded from Definition 15
19. FGS Functions 15
a. Elements of FGS 15
b. Approach and Landing System 15
c. Flight Management System (FMS) 16
d. Design Philosophy 16
e. Description of FGS Behavior and Operation 16
20. Compliance with § 25.1329 16
a. General 16
b. Relevant Paragraphs 16 Table 2-1 Cross-References § 25.1329 Paragraphs to AC Chapters 17 21 – 26 [RESERVED] 22
Chapter 3. FGS Engagement, Disengagement, Indications, and Override
27. Autopilot Engagement, Disengagement, and Indications 23
a. Autopilot Engagement 23
(1) Single Switch Action 23
(2) Engagement Status of Autopilot 23
(3) Multiple Autopilots 23
(4) Acceptable Transients 23 1
Paragraph Page
(5) Flight Director (FD) Not Engaged 23
(6) FD Engaged 24
b. Autopilot Disengagement 24
(1) General 24
(2) Autopilot Disengagement Alerts 25
(3) Quick Disengagement Control 26
(4) Alternative Means of Autopilot Disengagement 26
(5) Flightcrew Pitch Trim Input 27
28. FD Engagement, Disengagement, and Indications 27
a. FD Engagement 27
(1) General 27
(2) Guidance Cue(s) 28
(3) Reactive Windshear Guidance System 28
b. FD Disengagement 29
29. Autothrust Engagement, Disengagement, and Indications 29
a. Autothrust Engagement 29
(1) Indication 29
(2) Accessibility of Controls 29
(3) Inadvertent Engagement/Disengagement 29
(4) Automatic Engagement 29
b. Autothrust Disengagement 30
(1) Indication of Disengagement 30
(2) Inadvertent Disengagement 30
(3) Consequence of Disengagement 30
(4) Autothrust Quick Disengagement Control 30
30. Override of the FGS 31
a. General 31
b. Autopilot Override 31
(1) With Automatic Disengagement 31
(2) Without Automatic Disengagement 31
c. Autothrust Override 32
(1) Force Required 32
(2) Response to Override 32
(3) Engagement Status with Override 32
31. FGS Engagement Mode Compatibility 33
a. FGS Mode Engagement Philosophy 33
b. Engagement Mode Compatibility 33 32 — 41. [RESERVED] 33
Chapter 4. Controls, Indications, and Alerts
Paragraph Page
42. General 35
a. Human-Machine Interface 35
b. Design of Controls, Indications, and Alerts 35
c. Evaluation of Information Provided by FGS 35
43. FGS Controls 35
a. General 35
b. Design Considerations 35
(1) Differentiation of Knob Shape and Position 35
(2) Design to Support Correct Selection of Target Values 36
(3) Commonality Across Aircraft Types 36
(4) Positioning of Controls and Related Indications 36
(5) Inadvertent Operation 36
44. FGS Mode Selection, Annunciation, and Indication 36
a. Annunciation of Engagement of the FGS 36
b. Description of FGS Modes 36
c. FGS Mode Annunciations 36
(1) Active and Armed Modes 36
(2) Location 37
(3) Discriminators 37
(4) Color 37
d. Mode Changes 37
(1) Operationally Relevant Mode Changes 37
(2) Attention-Getting Features 37
(3) Use of Alerts 38
e. Failure to Engage or Arm 38
f. FGS Mode Display and Indications 38
45. FGS Alerting, Warning, Caution, Advisory, and Status 38
a. General 38
(1) Alerting Provisions 38
(2) Determination of FGS Capability 38
b. Speed Protection Alerts 38
(1) Alerts to Crew 38
(2) Alert Specifications 39
(3) Consistency 39
(4) Nuisance Alerts 39
c. Loss of Autopilot Approach Mode 39
d. Awareness of Potential Significant Transient Condition (“Bark Before Bite”) 39
(1) General 39
(2) Flightcrew Alert(s) 39
(3) Situations to Consider for an Alert 40 3
Paragraph Page
(4) Automatic Disengagement 40
46. FGS Considerations for Head Up Displays (HUD) 41
a. General 41
b. Characteristics of HUD Guidance 41
(1) Supplemental Use Display System 41
(2) External Visual References 41
(3) Interference and Occlusion 41
(4) Display Criteria 42
(5) Conformal Symbology 42
(6) Low Visibility Approach 42
(7) Clutter 42
c. HUD/Head Down Display (HDD) Compatibility 42
(1) General 42
(2) Consistency and Compatibility 42
d. Alerting Issues 43
(1) Alerts Displayed on HUDs 43
(2) Monochrome HUDs 44
(3) Mulit-Color HUDs 44
(4) Single HUD Installation 44
(5) Dual HUD Installations 44
(6) Ground Proximity Warning System (GPWS)/Traffic Alert and Collision Avoidance System (TCAS) Alerts On HUD 44
e. Upset/Unusual Attitude Recovery Guidance 44
(1) Guidance Cues 44
(2) Orientation Cues 45 47 – 51. [RESERVED] 45
Chapter 5. Performance of Function
52. General 47
a. Intended Function 47
b. Effect of System Tolerances 47
53. Normal Performance 47
a. General 47
b. Conditions to Consider 47 Table 5.1 Examples of Normal Conditions 48
c. Level of Performance 49
(1) Significant Characteristics 49
(2) Configuration Changes 49
(3) Compliance Evaluation 49
(4) Prescribed Levels of Performance 49
(5) Equivalence of Performance 49
(6) Autopilot 49 4
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(7) Flight Director (FD) 49
(8) Autothrust 49
(9) Automatic Trim 49
54. Performance in Rare Normal Conditions 50
a. General 50
(1) Range of Conditions 50
(2) Effect on Performance 50
b. Conditions to Consider 50 Table 5-2 Examples of Rare Normal Conditions 51
c. Level of Performance 52
(1) Performance Standard 52
(2) Autopilot Authority Limit 52
(3) Masking of Potential Hazard 52
55. Icing Considerations in Normal and Rare Normal Conditions 52
a. Effect on Performance 52
b. Alerts 52
c. Effect on Speed Protection 53
56. Performance in Non-Normal Conditions 53
a. General 53
b. Considerations to Consider 53 Table 5-3 Examples of Non-Normal Conditions 54
c. Level of Performance 55
(1) Performance Standard 55
(2) Autopilot Authority Limit 55
(3) Masking of Potential Hazard 55
57. Speed Protection 55
a. General 55
(1) Speed Excursions 55
(2) Compliance with § 25.1329(h) 55
(3) Design Standard 56
b. Low Speed Protection 57
(1) General 57
(2) Factors to Consider 57
(3) Low Speed Protection During Approach Operations 57
(4) Windshear Recovery Guidance 59
c. High Speed Protection 59
(1) General 59
(2) Factors to Consider 59 58 – 61. [RESERVED] 60
Chapter 6. Characteristics of Specific Modes
Paragraph Page
62. General 61
63. Lateral Modes 61
a. Heading or Track Hold 61
b. Heading or Track Select 61
c. Lateral Navigation (LNAV) Mode 61
(1) Lateral Flight Path 61
(2) Automatic Mode Transitions 61
(3) Takeoff or Go-Around (TOGA) 62
64. Vertical Modes 62
a. Target Altitude Selection 62
b. Vertical Speed 62
c. Flight Path Angle 62
d. Indicated Airspeed (IAS)/Mach Hold [speed on elevator] 62
e. Indicated Airspeed (IAS)/Mach Select [speed on elevator] 62
f. Flight Level (FL) Change [speed on elevator] 63
g. Altitude Capture 63
(1) Mode Transition 63
(2) Guidelines for Altitude Capture Mode 63
h. Altitude Hold 64
(1) Entering Mode 64
(2) Mode Transition Annunciation 64
(3) Barometric Pressure Adjustment 64
i. VNAV 65
(1) FMS Path 65
(2) Climb or Descent 65
65. Multi-Axis Modes 66
a. Takeoff Mode 66
(1) Vertical Guidance 66
(2) Lateral Guidance 66
(3) Rotation Guidance 66
(4) Autothrust 66
(5) Operation and Performance 66
b. Go-Around Mode 67
(1) Vertical Elements 67
(2) Speed 67
(3) Autothrust 67
(4) Engagement 68
(5) All Engine and Engine Out Capability 68
c. Approach Mode 68
(1) Final Approach Path 68
(2) Mode Annunciations 68 6
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(3) Sub-Modes 68
(4) Mode Engagement Sequence 68
66. Autothrust Modes 68
a. Thrust Mode 68
b. Speed Mode 68
c. Retard Mode 69
67. Special Considerations for VNAV Approach Operations Related to Selecting a Target Altitude 69
a. Approach Operations 69
b. VNAV Path Operations 69
68. Control Wheel Steering (CWS) [control steering through the autopilot] 69
a. General 69
b. Design 69
(1) Control Forces 69
(2) Bank and Pitch Attitudes 70
(3) Control Behavior 70
(4) Stall and Stall Recovery 70
(5) Adjustments to Trim 70
(6) Takeoff and Landing 70
(7) Automatic Reversion to CWS Mode 70
c. Terminology 71
(1) Touch Control Steering (TCS) 71
(2) Supervisory Override 71
69. Special Considerations for the Integration of Fly-by-Wire Flight Control Systems and FGS 71
a. Speed Protection 71
b. System Degradation 71 70 – 74 [RESERVED] 71
Chapter 7. FGS Integration
75. General 73
76. System Integration Issues 73
a. Common and Cascading Failure Modes 73
b. Risk of Error 73
c. System Safety Analysis 73
77. Functional Interfaces 74
a. Interfacing Sensors 74
b. Potential Inconsistencies Between Systems 74
c. Function and Performance 74 78 – 82 [RESERVED] 74
Chapter 8. Safety Assessment
Paragraph Page
83. General 75
a. Basic Safety Requirements 75
b. Safety Assessment 75
c. Validation of Safety Assessment 75
d. Coordination with the FAA 75
84. FGS Failure Conditions 75
a. Functionality 76
b. Effect of Failure Condition 76
85. Type and Severity of Failure Conditions 76
a. Types of Failure Conditions 76
(1) Loss of Function 76
(2) Malfunction 77
b. Cause 77
c. Severity 77
d. Assessment of Failure Conditions 77
(1) Functional Failures 77
(2) Airframe Loads 77
(3) Assessing Total Effect of Failure 78
86. Mitigation of Failure Conditions 78
a. General 78
b. Identification of Methods 78
c. FGS De-Selection 78
87. Validation of Failure Conditions 78
a. General 78
b. Validation Options 79
c. Validation Methodology 79
88. Specific Considerations 79
a. FGS Action During Ground Operations 79
b. FGS Operations in Close Proximity to the Ground 79
(1) Takeoff 80
(2) Approach 81
c. Cruise Operations 82
d. Asymmetric Thrust During Autothrust Operation 82
89. Failure to Disengage the FGS 83 90 – 97 [RESERVED] 83