L-13A Blaník lands hard after a sharp push in a balloon drill

At Plasy, a student's sharp push correcting a simulated balloon in a landing drill drove an L-13A Blaník hard onto the runway; both occupants were unhurt, but the glider was substantially damaged. In the round-out the instructor pulled back to make the glider float up. The student rightly began closing the airbrakes but pushed the stick forward sharply rather than gently, and the glider pitched steeply down. The instructor, not set up after the demonstration to catch a sharp input, pulled fully back and locked the airbrakes, but the main wheel struck the grass hard and the gear mounting was damaged.

1. Landing-correction exercise: The student and an instructor took off from RWY 21 at Plasy at 10:10 for a circuit practising the correction of faulty landings.
2. Instructor simulates a balloon: In the round-out the instructor pulled the stick back to demonstrate how the glider behaves when it floats up.
3. Sharp push on the stick: The student correctly began closing the airbrakes but at the same time pushed the stick forward sharply rather than gently; the glider pitched into a steep, nose-down descent.
4. Instructor not ready to react in time: After the demonstration the instructor had taken no measures that would let him react in time to a sharp elevator input from the student.
5. Full back-stick, airbrakes locked: The instructor pulled the stick fully back and then locked the airbrakes in the closed position.
6. Hard main-wheel strike; both unhurt: The main wheel struck the grass hard about 150 m past the RWY 21 threshold and the glider stopped after a short roll. The gear mounting and fuselage skin were damaged.