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 63-00-00 – MAIN ROTOR DRIVE 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 6310 Engine/ Transmission Coupling Provide torque Loss of engine TO Aircrew workload Analysis and and rotational to increases substantially Test speed to the transmission such that tasks cannot rotor shaft (coupling) drive (single engine).
be completed accurately. Aircrew must conduct an autorotation.
Loss of engine to transmission (coupling) drive (dual engine).
TO Aircrew workload substantially increases to handle an OEI condition.
Analysis and Test Loss of engine TO Continued safe flight is Analysis and coupling and not guaranteed due to Test loss of input seizure of free wheeling module free- clutch results in loss of wheeling MR rpm. Leads to clutch (single uncontrolled flight (no & dual auto-rotation engine). capability.).
Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 34
ATA 63-00-00 – MAIN ROTOR DRIVE 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 6320 Main Rotor Gearbox Provide torque and rotational speed to the rotor shaft.
Loss of lubrication to main transmission.
Cruise Aircrew workload increases substantially due to the need to conduct a landing as soon as possible.
Analysis and Test 6321 Main Rotor Brake Provide braking to the rotor Inadvertent activation of rotor braking system during flight.
ALL Continued safe flight is not guaranteed. For instance, engagement of the braking pad during high power to the main rotor could create a fire.
Analysis and Test 6340 Rotor Drive Indicating System Provide MGB chip detection Failure of chip detector system to detect and annunciate the existence of chips.
ALL Continued safe flight and landing is not guaranteed due to the degradation of gears below the required load capability.
Analysis and Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 35
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 63-00-00 – MAIN ROTOR DRIVE 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 Provide MGB Loss of oil ALL A significant reduction Analysis and oil pressure pressure in safety margins would Test indication indication. exist due to the possible delay in crew action to an actual loss of oil.
Aircrew workload increases slightly due to changing the planned flight and the monitoring of secondary indications.
Erroneous ALL A substantial reduction Analysis and annunciation in safety margins would Test of low oil exist due to the delayed pressure reaction of the crew to warning. an actual loss of oil.
Slight increase in aircrew workload due to conflicting low oil pressure warning and oil pressure indicator.
Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 36
ATA 63-00-00 – MAIN ROTOR DRIVE 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 Loss of oil ALL Large reduction in the Analysis and pressure aircraft safety margin; Test indication and cannot determine if low oil adequate oil pressure is pressure present. Secondary warning. cues may be present to pilot (Increase oil temperature, vibration and noise levels, in case of actual loss of MGB oil).
Substantial increase in aircrew workload.
Misleading oil ALL Significant reduction in Analysis and pressure the aircraft safety Test indication. margin due to erroneous oil pressure indication (reads normal but actual oil pressure is low).
Substantial increase in aircrew workload.
Misleading oil ALL Continued safe flight is Analysis pressure not guaranteed due to indication and loss of all indications of loss of low oil MGB oil pressure loss pressure and ensuing gearbox warning. seizure.
Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 37
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 63-00-00 – MAIN ROTOR DRIVE 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 Provide Nr indication Loss of rotor RPM (Nr) indication.
ALL Slight increase in aircrew workload due to the need to monitor secondary engine instruments.
Analysis and/or Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 38
ATA 73-00-00 - ENGINE FUEL AND CONTROL 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 7331 Fuel Flow Indicating Loss of fuel flow.
ALL The reduction in safety margins and functional capability in the system may prohibit continued safe flight and landing.
Analysis Malfunction and loss of fuel flow indication.
ALL The failure can delay crew action long enough to prevent continued safe flight and landing.
Analysis Misleading fuel flow alert failed.
ALL A large reduction in safety margins or functional capabilities.
Analysis 7332 Fuel Pressure Indicating Loss of fuel pressure.
ALL The reduction in safety margins and functional capability in the system may prohibit continued safe flight and landing.
Analysis Malfunction and loss of fuel pressure indication.
ALL A combination of a malfunction with a loss of indication in the system can delay crew action long enough causing a large reduction in safety margins or functional capabilities.
Analysis and Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 39
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 73-00-00 - ENGINE FUEL AND CONTROL 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 Misleading fuel pressure indication.
ALL If the indication to the pilot is a warning, the likely requirement is to land immediately.
Worst case is ditching in poor conditions causing a large reduction in safety margins or functional capabilities.
Analysis Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 40
ATA 75-00-00 - AIR 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 7510 Engine Anti- Icing (A/I) System Loss of a single engine A/I system on a multi-engine aircraft.
Cruise A significant loss of safety margin due to loss of a critical redundant system.
Significant increase in pilot workload.
Analysis and Test Loss of engine A/I system on a single engine aircraft.
Cruise Results in a large reduction in aircraft safety margin and a large increase in pilot workload.
Analysis and Test 7532 Compressor Bleed Valve Malfunction valve is failed OPEN on one engine of a multi-engine aircraft.
Cruise May cause an engine stall or surge that leads loss of one engine.
Significant increase in pilot workload.
Analysis and Test Malfunction valve is failed OPEN on one engine on a single engine aircraft.
Cruise May cause an engine stall or surge that leads loss of the engine.
More than a significant increase in pilot workload as the crew will likely have to land as soon as possible.
Analysis and Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 41
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 fail ure condition description but in the systems description or assumptions section.
ATA 75-00-00 - AIR 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 7540 Bleed Air Indicating System Loss of bleed air indication.
ALL A slight reduction in safety margins.
A slight increase in pilot workload.
Analysis and Test Misleading bleed air indication.
ALL Misleading indication may cause an inappropriate engine setting resulting in a significant reduction in system safety margins.
Analysis and Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 42
ATA 79-00-00 – OIL 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 7931 Engine Oil Pressure Loss of oil press indication.
ALL Loss of indication can delay crew action long enough to prevent continued safe flight and landing.
Analysis Misleading oil press indication.
ALL If the indication to the pilot is a warning, the likely requirement is to land immediately.
Worst case is ditching in poor conditions causing a large reduction in safety margins or functional capabilities.
Analysis and Test 7932 Engine Oil Quantity Loss of oil quantity indication.
ALL Loss of indication is considered to be a significant increase to pilot workload but only when required to be displayed per 14 CFR
29.1337(d)(2).
Analysis Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 43
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 79-00-00 – OIL 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 Misleading oil quantity indication.
ALL If the indication to the pilot is a warning, the likely pilot action is to land immediately.
Worst case is ditching in poor conditions causing a large reduction in safety margins or functional capabilities.
Analysis and Test 7933 Engine Oil Temperature Loss of oil temperature indication.
ALL Loss of indication in the system can delay crew action long enough to cause a large reduction in safety margins or functional capabilities.
Analysis and Test Misleading oil temperature indication.
ALL If the indication to the pilot is a warning, the likely requirement is to land immediately.
Worst case is ditching in poor conditions causing a large reduction in safety margins or functional capabilities.
Analysis and Test Figure AC 29 MG 21-1. Generic Examples by ATA.
Page MG 21 - 44
CHAPTER 3
AIRWORTHINESS STANDARDS
TRANSPORT CATEGORY ROTORCRAFT
MISCELLANEOUS GUIDANCE (MG) AC 29 MG 22 ROTORCRAFT ONE ENGINE INOPERATIVE (OEI) TRAINING MODE.
a. Purpose. This guidance provides a means to achieve airworthiness approval for OEI training mode to be installed on rotorcraft. These devices have been mainly designed to allow category A training without using the OEI ratings thus eliminating the need of extra maintenance for the engines and drive system. This guidance does not change the regulatory requirements and does not authorize changes in, or deviations from, regulatory requirements. These guidelines are developed for category A rotorcraft. If an applicant would like to develop such a system for category B rotorcraft, additional requirements may be applied by the certification authority.
b. References and Related Documents.
(1) 14 CFR parts 21, 29, 33, and corresponding European Requirements (Certification Specifications) part 21, CS-29, CS-E.
(2) AC 29-2C.
c. Background. Different types of OEI training modes and similar systems have been developed and are likely to be developed in the future. Their intent was to provide operators with a means to simulate OEI conditions for training purposes without using the engine and drive system OEI ratings. This type of installation requires an appropriate level of qualification, commensurate to the criticality of the most severe effects on the rotorcraft.
d. Definitions. OEI Training mode: for the purpose of this guidance material, a system or device designed to train the flightcrew by simulating, with an appropriate weight, the OEI conditions, reducing the power of the engines without accessing the actual OEI engine and drive system ratings. This includes cockpit controls and display indications necessary for the flightcrew to safely operate the system or device.
e. Certification Approach. There are different basic aspects to consider when approaching an OEI Training Mode that should be addressed in the proposed certification plan.
(1) System purpose definition. The cert ification process should begin with a clear declaration of the objective of the OEI training mode. Past experiences have shown that these type of systems have been mainly designed to allow operators to train their flightcrew on category A procedures without cutting one engine to idle through the Page MG 22 - 1