a.  Any emergency

    b.  Split-S

        The Split-s maneuver combines the first half of an aileron roll with the last half of a loop.

NOTE - Student solos are strictly prohibited from performing the Split-S, One-half Cuban Eight, Immelman, and intentional sustained inverted flight maneuvers.  Failure to comply with this safety related restriction is considered sufficient grounds for attition from flight training.

        The Split-S provides a means of rapidly converting the potential energy of altitude into airspeed while reversing the direction of flight.  Once the pull is commenced from the inverted position, airspeed builds rapidly and altitude is quickly lost.  If performed correctly, the altitude loss should be approximately 1500’.  Remember to select a long, well defined section line which extends behind as well as in front of you.

        Procedures:

        1)  THREE C’S.  POWER TO IDLE, MAINTAIN ALTITUDE.  Transition to aerobatic cruise and complete the aerobatic checklist.  Commence a clearing turn.  During the last 90 degrees of turn, reduce power to idle and apply back stick pressure as necessary to maintain altitude.  Roll out and continue to maintain altitude, slowing to 130 kts.  Be sure to add right rudder as airspeed decreases.

        2)  APPROXIMATELY 130 KTS, PLACE THE EXHAUST STACKS ON THE HORIZON.  RELAX BACK STICK PRESSURE.  Raise the nose to place the exhaust stacks on the horizon, relax the back stick pressure and roll in either direction using aileron and rudder to the inverted position.

        3)  ROLL INVERTED WITH AILERON AND RUDDER (RIGHT).  Once inverted, neutralize the ailerons and apply slight forward stick pressure to momentarily maintain straight and level flight.

        4)  CHECK WINGS LEVEL.  Quickly verify that the wings are level by referencing the horizon and correct as necessary.

        5)  APPLY BACKSTICK.  Apply back stick pressure, pulling the nose through the horizon and flying the aircraft along the section line as in the last half of the loop.  You’ll probably pull about 3.5 G’s.

        6)  RELAX RIGHT RUDDER PRESSURE AS AIRSPEED IS REGAINED.  Decrease right rudder pressure as the aircraft accelerates to recovery airspeed.

        7)  Check oil pressure within normal limits.  Reset aerobatic cruise power and report the oil pressure over the ICS.

        ICS:  “SIR, OIL PRESSURE IS 65 PSI.”

        Common errors:
 
        1)  Failure to maintain altitude and/or balanced flight during the deceleration.

        2)  Delaying roll initiation resulting in airspeed decay which equates to difficult lateral control.

        3)  Failure to obtain, check and/or correct wings level prior to pullout.  This results in disorientation and a rolling pullout.

        4)  Pulling too much back stick before sufficient airspeed has been gained resulting in a near stalled AOA.

    c.  Immelmann (also known as a “Hail Mary”)

        The Immelmann combines the first half of a loop followed by a half-roll to the wings level attitude.  It achieves a 180 degree change of direction of flight and a gain in altitude of approximately 1500 feet.

        This maneuver offers a quick means of reversing the direction of flight while trading excess airspeed for increased altitude.  Remember to select a long, well defined section line which extends behind you as well as in front of you.

        Procedures:

        1)  THREE C’S.  Transition to aerobatic cruise and complete the aerobatic checklist.  Commence a clearing turn.  During the last 90 degrees of turn, lower the nose slightly and accelerate to 200 kts.  Roll out of the clearing turn on or parallel to a section line with 200 kts.  The increased airspeed will require a slight amount of left rudder to maintain balanced flight.

        2)  Recheck the wings level and clear the airspace above you.

        3)  NOTE THE ENTRY ALTITUDE.  Check and report the entry altitude:

        ICS:  “ENTRY ALTITUDE IS 7,500 FT”

        4)  COMMENCE PULL-UP TO OBTAIN 3.5 G’S IN 2-3 SECONDS.  AGSM.  Commence the AGSM and immediately start a smooth straight pull up accelerating to 3.5 G’s within 2-3 seconds.  Do not use aileron.

        5)  KEEP THE WINGS LEVEL.  INCREASE RIGHT RUDDER PRESSURE AS AIRSPEED IS LOST.  Recheck the wings level as the nose passes through the horizon.  Adjust stick pressure as necessary to keep the nose moving at a constant rate.  Increase right rudder pressure as airspeed decreases.

        6)  TILT HEAD BACK TO FIND THE OPPOSITE HORIZON.  RECHECK WINGS LEVEL.  Shortly after passing the vertical position, tilt your head back and visually locate the opposite horizon.  Correct with aileron as necessary to maintain the wings parallel to the horizon.

        7)  RUDDER.  Check the nose in relation to the section line and correct directional deviations as necessary by adjusting the rudder input.

        8)  As the nose approaches a point 20 degrees above the opposite horizon (canopy bow on the horizon), slow the rate of nose movement by neutralizing back stick pressure.
 
 

        9)  ROLL UPRIGHT.  Commence a roll in either direction to the upright position using aileron and rudder.  Anticipate the need for slight forward stick pressure as the aircraft passes 90 degrees of roll.  Rudder input should initially be opposite the direction of roll, followed by a reversal to the same direction as the aircraft passes the wings vertical position.

       10)  The maneuver is complete when the aircraft is once again in the level flight attitude on the reciprocal heading.  The airspeed should be approximately 100 kts.  The nose attitude will therefore be slightly nose high.

        Common errors:

        1)  Failure to check and report the altitude prior to entry.  It’s hard to recover on the same altitude when you don’t know what it is!

        2)  Poor directional control caused by failure to maintain balanced flight with the proper amount of right rudder as airspeed is lost and then regained.  Poor rudder control is easily detected by checking the alignment of the nose and the section line.  Remember that the required rudder input varies as airspeed varies.  Almost constant rudder adjustment will be required.

        3)  Poor directional control caused by failure to keep the wings parallel to the horizon throughout the maneuver.  The most common tendency by far is to pull the stick slightly to the right when pulling the nose up during the 3.5 G entry.  Keep the stick centered longitudinally as the entry input is made.  Check and correct the wing attitude often.

        4)  Poor execution of the initial pull-up with respect to G loading and/or timing.  Remember 3.5 G’s in 2-3 seconds.  Scan the accelerometer.  Excessive G loading and/or loading the aircraft too quickly will cause an excessively rapid deceleration and may result in overstress.  Insufficient G loading, or taking too long to obtain the correct acceleration, will deplete the aircraft’s energy state, resulting in a stalled or near stalled condition when approaching the inverted position.

        5)  Commencing the roll to upright attitude either too early or too late.

        6)  Utilizing improper rudder and/or poorly coordinated rudder inputs during the roll.

2.  Demonstrate/Introduce:

    a.  Immelmann (non-graded)
        Refer to section 1.c above.

    b.  Split-S (non-graded)
        Refer to section 1.b above.

3.  Practice:

    a.  Loop
    b.  Wingover
    c.  Aileron roll
    d.  Barrel roll
    e.  Precision landings
    f.  Angle-of-attack approaches

4.  Non-graded:

    a.  Course rules (DEP, OFO, HFE)
    b.  ATS
    c.  Spin
    d.  PPEL
    e.  LAPL
    f.  LAPL(P)