AC 29-2C, Chg 7 2/4/2016
(vii) Supporting Material. For those failure conditions whose aircraft behavior effects are not well defined, additional supporting material (e.g., simulation, studies, flight test) should be defined to validate the chosen classification.
(viii) Verification Method. For each failure condition, the applicant should determine how the aircraft or system design would satisfy the safety objective. Some example entries are provided in Figure AC 29 MG 21-1 such as detailed documents or report numbers used in the supporting material section.
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ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method 2211 Autopilot Computer Loss of autopilot. ALL The detection of the loss of system by the crew could be delayed long enough to significantly reduce the safety margins or functional capabilities.
Analysis and Flt Test Malfunction (hardover) in a single axis.
Hover, TO App/Lnd Aircraft responds with a rapid attitude change, resulting in a possible departure from stable flight, or impact with terrain or ground-based obstacles.
Substantial increase in aircrew workload to recover from the resulting unusual attitude.
Minimal effect on occupants as they will be required to be seated and belted during this phase of operation.
Analysis and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
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AC 29-2C, Chg 7 2/4/2016 Note: Not all ATA chapters or subchapters have been included. Also, the italicized entries are not usually included in the failure condition description but in the systems description or assumptions section.
ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Malfunction (hardover) in a single axis.
Cruise Aircraft responds with a rapid attitude change, resulting in a possible departure from stable flight Substantial increase in aircrew workload to recover from the resulting unusual attitude prior to departure from stable flight.
Unrestrained occupant injuries resulting from the abrupt attitude changes of the aircraft.
Analysis and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
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ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Malfunction (slowover) in a single axis.
Hover, TO App/Lnd Aircraft responds with a slow attitude change, resulting in an unusual attitude situation. This could result in an Analysis and Flt Test airspeed, attitude or yaw outside the approved limits (depart stabilized flight) or result in a ground impact.
Substantial increase in aircrew workload to recognize and recover from the resulting unusual attitude prior to departure from stable flight and without impacting the ground.
2212 Pitch Attitude Control Annunciated loss of pitch stabiliza tion.
ALL Aircraft reverts to unaugmented pitch control.
Slight increase in aircrew workload to maintain pitch attitude.
Occupants may encounter some slight discomfort.
Analysis and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
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AC 29-2C, Chg 7 2/4/2016 Note: Not all ATA chapters or subchapters have been included. Also, the italicized entries are not usually included in the failure condition description but in the systems description or assumptions section.
ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Unannunc iated loss of pitch stabiliza tion.
ALL Significant reduction in safety margins due to the delay in pilot reaction to take control.
Significant increase in aircrew workload due to the delayed recognition and recovery of pitch attitude.
Occupants may encounter some slight discomfort.
Analysis and Flt Test 2216 Autopilot Trim Loss of autopilot trim (IFR).
ALL Slight reduction in safety margins due to loss of finite control.
Aircrew workload may increase significantly due to loss of automatic control.
Occupants may encounter some slight discomfort.
Gnd and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
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ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Unannunci ated malfunction (runaway).
Hover, TO App/Lnd Aircraft responds with a rapid attitude change, resulting in a possible departure from stable flight, or impact with terrain or ground-based obstacles.
Substantial increase in aircrew workload to recover from the resulting unusual attitude.
Occupant injuries and possible death resulting from the abrupt attitude changes of the aircraft and possible ground impact.
Analysis and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 9
AC 29-2C, Chg 7 2/4/2016 Note: Not all ATA chapters or subchapters have been included. Also, the italicized entries are not usually included in the failure condition description but in the systems description or assumptions section.
ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method 2250 Aerody namic Load Alleviating (Stability Augmenta tion) Loss of stability augmenta tion (VFR).
Hover A significant reduction in system margins is expected because of the inherent instability of most rotorcraft in hover.
The aircraft will lose short-term stability requiring a significant increase in workload is expected to maintain control.
Occupant injuries resulting from the abrupt attitude changes of the aircraft and possible ground impact.
Gnd and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
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ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Unannunci ated loss of Hover The information to the flight crew could be Analysis and Flt Test stability delayed long enough for augmenta the aircraft to attain an tion (IFR). unusual attitude, which significantly reduces the safety margins or functional capabilities.
The aircrew workload would significantly increase in order to recognize and recover from an unusual attitude and regain stable flight.
Occupant injuries resulting from the abrupt attitude changes of the aircraft and possible ground impact.
Figure AC 29 MG 21-1. Generic Examples by ATA.
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AC 29-2C, Chg 7 2/4/2016 Note: Not all ATA chapters or subchapters have been included. Also, the italicized entries are not usually included in the failure condition description but in the systems description or assumptions section.
ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Malfunction (hardover) in a single axis.
Hover, TO App/Lnd Aircraft responds with a rapid attitude change, resulting in departure from stable flight and possible ground impact.
Analysis and Flt Test Substantial increase in aircrew workload to recover from the resulting unusual attitude prior to departure from stable flight and possible ground impact.
Occupant injuries and possible death resulting from the abrupt attitude changes of the aircraft and possible ground impact.
Figure AC 29 MG 21-1. Generic Examples by ATA.
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ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Malfunction (hardover) in a single axis.
Cruise Aircraft responds with a rapid attitude change, resulting in an unusual attitude or departure from stable flight.
The aircrew workload would significantly increase in order to recognize and recover from an unusual attitude and regain stable flight.
Analysis and Flt Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 13
AC 29-2C, Chg 7 2/4/2016 Note: Not all ATA chapters or subchapters have been included. Also, the italicized entries are not usually included in the failure condition description but in the systems description or assumptions section.
ATA 22-00-00 – AUTO FLIGHT SYSTEM ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method Malfunction (slowover) in a single axis.
Hover, TO App/Lnd Aircraft responds with a slow attitude change, resulting in an unusual attitude situation. This could result in an Analysis and Flt Test airspeed, attitude or yaw outside the approved limits (depart stabilized flight) or result in CFIT.
Substantial increase in aircrew workload to recognize and recover from the resulting unusual attitude prior to departure from stable flight.
Occupant injuries and possible death resulting from the abrupt attitude changes by the pilot and possible CFIT.
Figure AC 29 MG 21-1. Generic Examples by ATA.
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ATA 23-00-00 - COMMUNICATIONS ATA Function Description Failure Condition (FC) Phase of Operation Effect of the Failure on the Aircraft, Crew and Occupants Classification of the FC Notes (assumptions) Supporting Material Verification Method 2300 Communica tion System Total loss of ALL radio communi cation with ATC and other aircraft (IFR).
ALL Aircrew workload would increase significantly for the requirement of the crew to increase awareness for other aircraft.
Significant reduction in safety margins as one level of protection against a collision is lost.
Analysis and / or test No effect on occupants.
Total loss of Aircrew workload would Analysis and ALL radio ALL slightly increase by / or test communicat setting 7600 on the ion with Transponder and ATC and changing the planned other flight by landing at an aircraft uncontrolled airfield or (VFR). receiving light signals from a controlled airfield.
Figure AC 29 MG 21-1. Generic Examples by ATA.
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