Cham Kiu: "The Whipping Fist"
by @jin-out on Brave-Smoke's Corner
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Working on a medium ranged attack, expressed by one of many hand's within Wing Chun's Second Form: Cham Kiu (Seeking The Bridge).
The Cham Kiu Uppercut, powered by the whip principle, as well as circular drilling motions (in this case expressed in an upward vector), aiming for the solar plexus primarily from a medium to short ranged distance.
This move is "shadow-less", requiring no wind-back (no preparation) in order to generate power. On it's own (and in a tense frame) this upwards "uppercut" is extremely weak; only when the principles of relaxation, of whipping, of circular motions, of upwards drilling, of forming a kinetic chain with your entire Scapula (one of many secrets of Wing Chun) are merged does this whipping uppercut create immense damage.
It's a hard move to block as often it's aimed at the organs such as Solar Plexus, Kidney, Liver. With an upwards drilling snapping/whipping motion, if the hit lands in any one of these locations, the upwards drilling impact is very difficult to pad/block against. With the principles of generating short form power in the tight Wing Chun frame (the secret's in the kinetic chain created by the Scapula muscles/structure), as well as rounding out the lower back (another secret of Wing Chun) upon the drilling-whip-uppercut's impact, and the clenching of the toes as the impact is delivered (another of Wing Chun's secret), this you can imagine is a deadly weapon.
Adding to this the principles of the 45 degree turn (marked by the horizontal and vertical "X" at the start of both the 1st and 2nd form), as well as stepping forward, this generates immense impact just from this seemlingly weak "uppercut".
Follow-up combinations after the Cham Kiu uppercut also offers many means of damaging the opponent further. For example, once the whip-drill-uppercut impact is felt in any of the body's weak location, such as the organs, it'll cause an instant gag-vomit reaction do to the upwards drilling impact that the body cannot defend against; if the impact lands on the kidney or liver that is an instant game changer and a possible neutralizer (though not a knockout). If the whip-uppercut is aimed at any of the nerves whether under the armpit, the under-side of the armpit, or the bicep muscles, or even the right under the front side of the shoulder's rotator cuff, this Cham Kiu uppercut will numb the entire arm from the armpit upwards...or it will numb neutralize all power from a tensed arm...or it will do serious damage to the shoulders and even (with enough force) dislocate the shoulder from the rotator cuff.