Fig. 1 shows the start position. Notice that Nage is in an Aiki stance. Kuta Irimi is the combining of Kuta and Aiki.
Fig. 2 shows the Kuta strike landing. The bag weighs 270 lbs. and Nage only weight 130 lbs. So it takes a powerful punch here to get the bag moving enough and Nage moving enough for this technique. The Knee Pop Stomp is essential for this.
Fig. 3 shows Nage rapidly moving in for the Aiki punch. Both of Nage's feet are in the air in a Pendulum Step.
Fig. 4 Aiki Punch
Fig. 5 Follow Through
Fig. 6 Irimi Step
Fig. 4 is where the Aiki strike lands. It is an edge of the hand blow to Uke's neck. The main difference in an Aiki strike and a Kuta strike is that the Aiki strike follows through into a throw instead of pulling back.
Fig. 5 shows the follow through where the palm of Nage's hand grabs Uke's head and drives it back with a powerful Tornado Twist.
Fig. 6 shows the end of the 2nd Irimi step. The spin and Pin is not done here to keep from damaging the punching bag.