Accelerated Stalls
Accelerated Stalls
Objective: The student will be introduced to what an accelerated stall is and how to recover if the situation occurs.
Completion Standards: The student will be able to explain what an accelerated stall is and how we can recover from one. The student will also be able to identify some situations where one can occur.
References: AFH, PHAK
Equipment: White Board and markers, iPad/ computer
IP’s Actions:
Assess student
State the objective and completion standards
Writes down references
Provide attention getter
Present content
Assessment
Assign Homework
SP’s Actions:
Take notes
Ask Questions
Introduction:
(Attention Getter) : during slow flight or during a stall and it bumpy. You stall sooner than the anticipated airspeed.
Motivation: (Discuss purpose for lesson and relate to Attention getter)
Overview:
Characteristics of a stall
Accelerated Stalls
Where Can They Occur?
Procedures
Common Errors
Content:
Exhibits instructional knowledge of the elements of accelerated maneuver stalls by describing:
Characteristics of a stall
Review of what a stall is
What is a stall:
A stall is an aerodynamic condition which occurs when smooth airflow over the airplane’s wings is disrupted, resulting in loss of lift
When the AOA—the angle between the chord line of the wing and the relative wind—exceeds the wing’s critical AOA
Stall Characteristics:
Factors that can affect the stall characteristics of an airplane
include its geometry, CG, wing design, and high-lift devices.
Explain how CG can affect stall characteristics
Design of wings
so that the wings stall progressively outward from the wing roots (where the wing attaches to the fuselage) to the wingtips
Twist, known as washout, resulting in the outboard portion of the wings having a slightly lower AOA than the wing roots
causes the wingtips to have a smaller AOA during flight than the wing roots. Thus, the wing roots of an airplane exceed the critical AOA before the wingtips, meaning the wing roots stall first.
the ailerons should still have a degree of control effectiveness until/unless stalled airflow migrates outward along the wings
Accelerated Stalls
The airplane can also stall at a higher indicated airspeed when the airplane is subject to an acceleration greater than +1G
Where Can They Occur?
When turning Improperly executed turns,
Pulling up, Pullouts from steep dives,
Other abrupt changes in flightpath
Stall and spin recoveries,
Overshooting a base to final turn.
An accelerated stall is typically demonstrated during steep turns.
Procedures
Setup:
Select an altitude no lower than 3000’ AGL.
2.Perform the PRE-MANEUVER FLOW and make a position report (see page 2-26).
Entry/ Maneuver Flow:
Reduce power to 1500 RPM to allow the airplane to decelerate to 85 KIAS, adjusting pitch (trimming) to maintain altitude.
NOTE The flaps must be in the up position.
At 85 KIAS, establish a 45-50°bank to the left or right.
After the bank and turn are established, smoothly and steadily increase elevator back-pressure.
As the airspeed reaches 68 KIAS (20 knots above the unaccelerated stall speed), firmly increase elevator back-pressure.
Recovery:
When the stall warning activates:
Note the indicated airspeed
Call out, “Stall warning.”
Reduce the angle of attack to maintain control effectiveness.
Maintain coordinated use of the ailerons and rudder to:
Level the wings,
Prevent entering into a spin.
Apply full power and return to the altitude, heading, and airspeed specified.
Complete the CRUISE CHECKLIST(see page 1-80).
Common Errors
Failure to establish proper configuration prior to entry.
Improper or inadequate demonstration of the recognition of and recovery from an accelerated maneuver stall.
Failure to present simulated student instruction that adequately emphasizes the hazards of poor procedures in recovering from an accelerated stall.
2. Demonstrates and simultaneously explains accelerated maneuver stall from an instructional standpoint.
4. Analyzes and corrects simulated common errors related to accelerated stalls.
Conclusion
Characteristics of a stall
Accelerated Stalls
Where Can They Occur?
Procedures
Common Errors
(Questions to assess student)
In what situations can an acerated stall happen?
What is the recovery procedure?
HW:
Look over accelerated stalls in AFH or SOPM