Par 4-1 Page 15 CHAPTER 4. UPSET RECOVERY TEMPLATE
4-1. METHODOLOGY. Airplane manufacturers (Airbus, ATR Aircraft, Boeing, Bombardier, and Embraer) contributed to the development of the following upset recovery templates that provide commonality among various airplanes.
4-2. UPSET RECOVERY TEMPLATES. Tables 1 and 2 show the Nose High and Nose Low Upset Recovery Templates that were developed with input from the above manufacturers.
Although the procedures apply to the majority of today’s airplanes, manufacturer-recommended procedures may deviate from those included in this advisory circular (AC) due to specific airplane characteristics. Manufacturer recommendations may deviate from this template if necessary due to airplane operating characteristics. For air carriers operating airplanes without manufacturer upset recovery procedures, the FAA recommends using the upset recovery templates as a reference when developing air carrier-specific upset recovery procedures.
NOTE: The manufacturer’s procedures take precedence over the recommendations in this AC.
NOTE: These techniques assume the airplane is not stalled. If the airplane is stalled, recovery from the stall must be accomplished first in accordance with the current edition of AC 120-109, Stall Prevention and Recovery Training, or manufacturer procedures.
a. The following techniques represent a logical progression for recovering the airplane.
While not strictly procedural, the templates represent a consensus view of actions for recovery.
b. If needed, use pitch trim sparingly. Careful use of rudder to aid roll control should be considered only if roll control is ineffective.
c. This section uses the following acronyms: AP for autopilot and A/THR for autothrottle/autothrust.
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4/14/15 AC 120-111 TABLE 1. NOSE HIGH RECOVERY TEMPLATE Either Pilot:
Recognize and confirm the developing situation. Announce: “Nose High” Pilot Flying Pilot Monitoring AP: DISCONNECT3 MONITOR airspeed and attitude throughout the recovery and ANNOUNCE any continued divergence. A/THR: OFF PITCH: Apply as much nose-down control input as required to obtain a nose-down pitch rate.
THRUST: Adjust (if required) When airspeed is sufficiently increasing:
RECOVER to level flight. 4 3 A large out-of-trim condition could be encountered when the AP is disconnected.
4 Avoid stall because of premature recovery or excessive G loading.
NOTE: Recovery to level flight may require use of pitch trim.
NOTE: If necessary, consider reducing thrust in airplanes with underwing-mounted engines to aid in achieving nose-down pitch rate.
WARNING: Excessive use of pitch trim or rudder may aggravate the upset situation or may result in high structural loads.
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4/14/15 AC 120-111 TABLE 2. NOSE LOW RECOVERY TEMPLATE Either Pilot:
Recognize and confirm the developing situation. Announce: “Nose Low” Pilot Flying Pilot Monitoring AP: DISCONNECT5 MONITOR airspeed and attitude throughout the recovery and ANNOUNCE any continued divergence. A/THR: OFF RECOVER from stall if required.
ROLL6 in the shortest direction to wings level.
THRUST and DRAG: Adjust (if required) RECOVER to level flight. 7 5 A large out-of-trim condition could be encountered when the AP is disconnected.
6 It may be necessary to reduce the G loading by applying forward control pressure to improve roll effectiveness.
7 Avoid stall because of premature recovery or excessive G loading.
NOTE: Recovery to level flight may require use of pitch trim.
WARNING: Excessive use of pitch trim or rudder may aggravate the upset situation or may result in high structural loads.
Par 4-2 Page 18 TABLE 3. NOSE HIGH RECOVERY TEMPLATE WITH EXPLANATION Either Pilot: Recognize and confirm the developing situation. Announce: “Nose High” Explanation: A critical element in recognition and confirmation is to clearly understand the energy state and the rate to which it is changing because this will have an effect on how the PF handles the recovery.
Pilot Flying AP: DISCONNECT8 A/THR: OFF Explanation: Leaving the autopilot or autothrottle/autothrust connected may result in inadvertent changes or adjustments that may not be easily recognized or appropriate, especially during high workload situations.
PITCH: Apply as much nose-down control input as required to obtain a nose-down pitch rate.
Explanation: This may require as much as full nose-down input. If a sustained column force is required to obtain the desired response, use nose-down trim as needed to counter high stick forces.
If nose-down inputs are not successful in achieving a nose-down pitch rate, pitch may be controlled by rolling the airplane. A large bank angle is helpful in reducing excessively high pitch attitudes. The angle of bank should not normally exceed approximately 60°. Continuous nose-down elevator pressure will keep the wing angle of attack low, which will make the normal roll controls effective. The rolling maneuver changes the pitch rate into a turning maneuver, allowing the pitch to decrease.
THRUST: Adjust (if required) Explanation: Combined with pitch trim, an additional effective method for achieving a nose-down pitch rate on airplanes with under-wing-mounted engines can be to reduce the power. Thrust should only be reduced to the point where control of the pitch is achieved. This reduces the upward pitch moment. In fact, in some situations for some airplane models, it may be necessary to reduce thrust to prevent the angle of attack from continuing to increase.
If the pitch rate is being managed by trim and elevator inputs, it is not recommended to reduce thrust.
8 A large out-of-trim condition could be encountered when the AP is disconnected.
Par 4-2 Page 19 TABLE 3. NOSE HIGH RECOVERY TEMPLATE WITH EXPLANATION (CONTINUED) RECOVER to level flight9 when airspeed is sufficiently increasing.
Explanation: Recover to slightly nose-low attitude to reduce the potential for entering another upset. Roll to wings level, if necessary, as the nose approaches the horizon. Check airspeed, and adjust thrust and pitch as necessary.
Pilot Monitoring MONITOR airspeed and attitude throughout the recovery and ANNOUNCE any continued divergence.
Explanation: Evidence shows that the PM is often in a better position than the PF to recognize adverse trends in airplane state or flight parameters.
9 Avoid stall because of premature recovery or excessive G loading.
Par 4-2 Page 20 TABLE 4. NOSE LOW RECOVERY TEMPLATE WITH EXPLANATION Either Pilot:
Recognize and confirm the developing situation. Announce: “Nose Low” Explanation: A critical element in recognition and confirmation is to clearly understand the energy state and the rate to which it is changing because this will have an effect on how the PF handles the recovery.
Pilot Flying AP: DISCONNECT10 A/THR: OFF Explanation: Leaving the autopilot or autothrottle/autothrust connected may result in inadvertent changes or adjustments that may not be easily recognized or appropriate, especially during high workload situations.
RECOVER from stall if required.
Explanation: Even in a nose-low, low-speed situation, the airplane may be stalled at a relatively low pitch. It is necessary to recover from the stall first. This may require nose-down elevator, which may not be intuitive.
ROLL11 in the shortest direction to wings level.
Explanation: Full aileron and spoiler input may be necessary to smoothly establish a recovery roll rate toward the nearest horizon. It is important that positive G force not be increased or that nose-up elevator or stabilizer trim be used until the airplane approaches wings level. It may be necessary to unload the airplane by decreasing backpressure to improve roll effectiveness. If the airplane has exceeded 90° of bank, it may feel like “pushing” in order to unload. It is necessary to unload to improve roll control and to prevent pointing a large lift vector toward the ground.
THRUST and DRAG: Adjust (if required) Explanation: If airspeed is low, apply thrust; if airspeed is high, reduce thrust and, if necessary, extend speedbrakes.
RECOVER to level flight.12 Explanation: Complete the recovery by establishing a pitch, thrust, and airplane drag device configuration that corresponds to the desired airspeed.
10 A large out-of-trim condition could be encountered when the AP is disconnected.
11 It may be necessary to reduce the G loading by applying forward control pressure to improve roll effectiveness.
12 Avoid stall because of premature recovery or excessive G loading.
Par 4-2 Page 21 (and 22) TABLE 4. NOSE LOW RECOVERY TEMPLATE WITH EXPLANATION (CONTINUED) Pilot Monitoring MONITOR airspeed and attitude throughout the recovery and ANNOUNCE any continued divergence.
Explanation: Evidence shows that the PM is often in a better position to recognize adverse trends in airplane state or flight parameters than the PF.
NOTE: Recovery to level flight may require use of pitch trim.
WARNING: Excessive use of pitch trim or rudder may aggravate the upset situation or may result in high structural loads.
Appendix 1 APPENDIX 1. TRAINING ELEMENTS AND EVENTS
1. Aerodynamics Academic a. General Aerodynamics:
• Aerodynamic flight envelope.
• Load factor.
• Directional and lateral control.
• Weight and balance effects on handling.
• Trim.
• Sideslip.
b. Advanced Aerodynamics:
• Lift versus drag (L/D) curve, L/D Max in particular, and significance on airplane performance in general.
• Relationship between L/D curve and airspeed.
• Airplane energy state and its application in various flight altitudes, airspeeds, and attitudes.
• Optimum climb speed, crossover altitude, optimum altitude, and maximum altitude as they relate to airplane performance and the effect of deviations (environmental or airplane) on performance.
• Thrust required versus thrust available.
• Thrust-limited conditions and recovery.
• Aerodynamic stability and its effects in flight including maneuvering stability and characteristics at high and low altitude; environmental impact on aerodynamics and handling (e.g., temperature, ice, etc.).
c. Airplane Performance (high and low altitude):
• Use of airplane (type-specific) performance charts to determine the effects of environmental, airplane configuration, or system changes on planned flight performance.
• Training pilots to understand that an airplane may not be able to reach its maximum certified altitude depending on performance at the time of the flight is critical. Pilots should also understand the possible consequences of choosing a cruising altitude that exceeds the airplane’s performance capabilities for the conditions existing at the time of the flight.
• Recognition of the different flight deck cues between low-speed buffet and high-speed buffet.
Appendix 1
d. Type-specific aerodynamics:
• Angle of attack (AOA) awareness including:
• Importance of AOA as it relates to airplane performance and wing stall angle.
• Effect of airplane configuration (e.g., flaps, gear, leading edge slats, speedbrakes, and thrust/power setting) on stall margins and stall characteristics.
• AOA relationship to various airplane systems, particularly warning systems (e.g., stall warning, stick shaker, stick pusher, etc.).
• General and airplane-specific AOA knowledge.
• Impact of environmental and system factors on AOA indications and their relationship to the stall AOA and various airplane warning systems (e.g., type-specific knowledge of the stall warning system).
• AOA indications, if presented to the pilot.
• Airplane-specific handling to use AOA-derived information to prevent or recover from an upset (including stall).
e. Mach effects including:
• Mach tuck and Mach buffet and the reason for them.
• Buffet-limited max altitude.
• Critical Mach number and aerodynamic forces acting on the wing at critical Mach.
• Control surface effectiveness at high speed.
Note: Training for AOA and Mach effects should only be accomplished to the extent of their applicability to the specific airplane.
Flight The FSTD training should be accomplished at both high altitudes (within 5,000 ft. of the service ceiling of the airplane), and low altitude (below 10,000 ft. above ground level (AGL)). Use of normal operational cruise altitudes for high-altitude training should be encouraged. To fully understand the concepts discussed in academic training, pilots should demonstrate the following:
• Recognize buffet (if applicable to airplane type), when encountered.
• Maneuvering at high altitudes at various speeds and automation levels applying the aerodynamic principles studied to prevent an upset.
• Awareness of the AOA from available data shown on the flight deck
(e.g., barber pole on speed tape, pitch-limit indicator, flight-path symbol relative to pitch attitude, etc.) and demonstrate the use of those data to prevent an upset or recover from one.
• Demonstrate knowledge of the type-specific systems that use AOA inputs with emphasis on warning systems and the limitations of those systems.
Appendix 1
• Speed controlled by elevator inputs or speed controlled by thrust, airplane energy state as it pertains to the type being flown, and demonstrate use of that knowledge to prevent or recover from an upset.
• Roll rate performance of the airplane at different speeds and different configurations and with flight spoilers retracted/extended if a difference exists.
• Pitch rate performance of the airplane at different speeds, different configurations, and with flaps retracted/extended.
• Demonstrate an aft center of gravity (CG) versus forward CG if flight qualities are significantly different.
Additional details regarding these areas can be found in the Airplane Upset Recovery Training Aid (AURTA) Revision 2, section 2.5. While the AURTA was designed for swept-wing airplanes with more than 100 seats, the general concepts are still applicable to most high-performance airplanes.
2. G Awareness Academic The effects of G’s, especially during airplane upsets. Emphasize that G-loading in transport category airplanes feels significantly more pronounced than in simulation. Airline pilots are normally uncomfortable (for the sake of passenger comfort and safety) with aggressively loading or unloading the G forces on a large passenger airplane. This inhibition must be overcome when faced with the necessity to quickly and sometimes aggressively maneuver the airplane. Most FFSs cannot replicate sustained load factors greater or less than 1G; therefore, the flight deck situation must be envisioned during flight different from 1G. The pilot may feel significantly heavier or lighter in the seat for moderate durations. It may be difficult to reach the rudder pedals.
Unsecured items may be flying around the flight deck. However, it should be emphasized that it should not normally be necessary to maneuver at less than 0G.
Flight Incorporated into Section 8, Upset Recovery Techniques, below.
3. Energy Management Academic • The interrelationship between kinetic energy (airspeed), potential energy (altitude), and chemical energy (power).
• How the airplane gets in a high- or low-energy state and the input options available to change the energy state to a stable and safe state.
• How external factors can change energy state and how to correct for them.
• What parameters to focus on to decide an appropriate response;
crosscheck with the other pilot to establish a shared understanding.
• What to monitor during an event and how the pilot monitoring (PM) should assist the pilot flying (PF) in the recovery using appropriate callouts and other verbal feedback.
Appendix 1 Flight This training should include integrated Crew Resource Management (CRM) training for developing crew knowledge and skills for energy management and techniques for reducing pilot error. To fully understand the concepts discussed in academic training, pilots should demonstrate the following:
• Acceleration between two speeds of which the airplane is capable at low altitude, medium, and high altitude (e.g., accelerating between 200 and 250 knots at low altitude and high altitude, which corresponds to Mach changes at high altitude) to demonstrate changes in available thrust.
• Acceleration performance from region of reversed command (back side of power curve) at low altitude and high altitude.
• The relationship between Maximum Cruise/Climb/Continuous Thrust and takeoff/go-around (TOGA) power settings at high altitude.
• Acceleration capabilities through descent versus power application.
• Wake vortex encounter behind a heavy airplane in takeoff and approach configuration.
4. Flightpath Management Academic Flightpath and energy management systems: Pilots should have a thorough understanding of the normal operation, failure modes and effects, and system integration effects of flightpath and energy management systems. Training on flightpath and energy management systems should include:
• Normal system operation and limitations.
• Indications and modes, including crosscheck and verification of mode use and understanding of how a specific mode will command the airplane; interoperability with other systems.
• Failure modes and effects.
• Common model-specific failures.
• Common errors to avoid and why they occur.
• The importance of ensuring correct inputs to the automated systems for flightpath management and the consequences of failing to do so.
• Understanding of type-specific characteristics to prevent inadvertent LOC-I events because of automation surprise (e.g., vertical speed (VS) or indicated airspeed (IAS) modes based on altitude).
• System review when conducting recurrent training.
• Knowledge of pitch attitudes, power settings, and airspeeds for common configurations and different phases of flight, as applicable to the airplane type.
Manual Flight Operations:
• Primary and alternate control strategies.
• Nonintuitive factors. For example, it may be counterintuitive to use greater unloading control forces when recovering from a high AOA, especially at low altitudes.
Appendix 1
• Additionally, for under-wing-mounted engines it may be necessary to reduce thrust in order to reduce the AOA due to the strong pitch up forces from added thrust.
• Specific aspects of the transition from automated to manual flight including transition from using a flight director to “raw data,” as applicable.
Flight Training should include abnormal operating conditions, reliance on primary flight instruments, manual flying skills, and edge-of-envelope operating conditions that could be encountered during routine operations. Examples include:
• Takeoff at high weight and aft/forward CG limits.
• Recognition and recovery from low-airspeed/energy condition in approach/landing configuration.
• Recognition and recovery from low-airspeed/energy condition near the service ceiling.
• Climb-to, steady state, and descent from service ceiling.
• Unplanned transition from automated to manual flight, including transition from using a flight director to “raw data,” as applicable.
5. Causes and Contributing Factors of Upsets Academic • Environmentally induced upsets, which could be caused by turbulence, mountain wave, wind shear, thunderstorms, microbursts, or airplane icing.
• Pilot-induced upsets which could be caused by misinterpretation or slow instrument crosscheck, improper adjustment of attitude and power, improper pilot input, inattention, distractions, spatial disorientation, pilot incapacitation, misunderstanding of autoflight modes or improper use of automated systems, transition from automated to manual modes due to system disconnect, and pilot-induced oscillation (PIO).
• Mechanically induced upsets that could be caused by flight instrument anomalies/failures, autoflight anomalies/failures, flight control malfunctions/failures, or other system anomalies.
• Common illusions (e.g., somatogravic illusion, the leans, Coriolis illusion, etc.) associated with LOC-I events. It should be explained why they occur and the importance of following procedure to avoid susceptibility to illusions.
• Situations resulting in an upset due to a lack of visual cues such as a sub-threshold roll (i.e., imperceptible roll rate, generally less than three degrees per second).
Flight Not applicable