Hanyu Quad Axel - Oh So Close

(11 Feb. 2022)  In pushing the the technical envelope in figure skating, quad Axel is now the Holy Grail.  Yuzuru Hanyu dedicated, and some might say sacrificed, his whole Olympic season to a quest to land the most difficult jump in the IJS scale of values.  At Japanese Nationals in December 2021, he attempted the jump and came up far short, with a downgraded, two footed attempt.

In the Men's Free Skate at The Beijing Winter Games, he attempted the jump once again, and this time he came oh so close to success, falling on the jump which was called under-rotated.

So how close did he come and what does it tell us if the jump is humanly achievable?

Like all triple Axel's executed in modern competition, the jump took off with one-quarter pre-rotation.  The landing was called under-rotated, and we peg the under-rotation at one-third rotation, for a total of 3.92 rotations in the air.  We also put the jump at 0.75 seconds in the air, for an average rotation rate of 5.2 rotations per second, and we put the peak rotation rate at 5.5 rotations per second.

The values for this attempt can be compared to the upper limits of performance for jumps, those approaching 0.80 seconds in the air and peak rotation rates of 6 per second, or a bit greater.

Taken together, a jump with Hanyu's rotation rate and 0.80 seconds in the air would be considered fully rotated by ISU rules, and a jump with Hanyu's time in the air and 6 rotations per second would also achieve full rotation. 

So what is it that kept this attempt from being successful?  The answer is pretty much the same as it was for the attempt at Japanese Nationals - air position.

At left we show Hanyu's air position two rotations into the jump.  The arms are too far from the torso and the legs are bent and too open.  This was true for over half the time in the air.  These defects in position eat up the top end of rotation rate needed to fully rotate the jump.

Most triples and even some of the quads do not require perfect air position for the entire time in the air to be successful, but the quad Axel does.  Our modeling is that had this attempt hit the perfect air position within the first rotation of the jump, the attempt would have had sufficiently greater rotation rate to have been successful.