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Sub-Gravity Sensations

A small percentage of the population appears to be sensitive to manoeuvres that produce loading below that normally experienced. The reaction to these reduced gravity manoeuvres is often similar to a child’s reaction to falling. Indeed the sub-gravity sensation can be thought of as ‘falling up’. Humans are ‘hard wired’ to protect their heads and eyes, and will react by shoving their hands out in the direction that they think they are falling or where a projectile is coming towards them. The sub-gravity sensation causes blood to rush to the head, much the same as occurs when we fall headfirst. Our natural reaction to this may result in pushing the stick forward if this is what we are gripping. Our training for stall recoveries, which can often leave the idea that you should push the stick forward to recover, further compounds this reaction. It is very important, therefore, to train students to “lower the nose” for such recoveries. The outline for this exercise is:

  1. Instructor demands performance by student of Pre-Takeoff Checks.
  2. Student follows through on controls during all phases of flight unless otherwise directed by the instructor.
  3. Students exhibiting good control skills may be coached through attempts at the takeoff. Instruc tor guides these closely, taking over as required.
  4. If student maintains good control they are allowed to continue to fly the aerotow. Instructor does not check student on performance of 300 feet call out, as this would be too distracting.
  5. If student having trouble maintaining good position on tow, then instructor takes over, with student following through. Checks the student’s performance of 300 feet call out.
  6. Student, under calm conditions, is allowed to attempt the aerotow above 1000 feet. Instructor’s guides this closely, taking over as required, establishing good position, and then letting the student try again.
  7. Instructor coaches student’s performance of lookout, release, and turn.. Once in level flight instructor checks student use of trim.
  8. Instructor checks the student’s performance in locating the airfield.
  9. Instructor checks students CALL check and linked turns. Requires good lookouts before each turn.
  10. Instructor checks student performance of a gentle stall and recovery. A demonstration of this is optional.
  11. Instructor demonstrates a sub-gravity sensation manoeuvre with the student not following through on the control column. Instructor puts aircraft into a 45 degree down dive until .75 Vne reached. Pitches aircraft up 45 degrees, and then pushes over the top.
  12. Students not upset by this manoeuvre are allowed to practise, and follow the sub-gravity exercise with a gentle stall.
  13. Instructor checks students performance of the downwind checks and student alone flies the aircraft.
  14. Instructor takes control after the turn on to final leg is completed, student continues to follow through on the controls.
  15. Students who exhibit good control skills may be coached through a landing at this stage.