The problem with any jumpkick is just that, you're jumping.

You don't have a solid base, your centre of gravity is way off.
There's a reason why they call it a sacrifice kick (Sutemi Waza?) in Karate terms.

In Judo terms, you just helped your opponent do perform 1/2 of a throw. He doesn't need to think how to elevate you anymore he just got to figure out how to slam you as hard as possible to the ground.

For your info, I think it would be easier for you to find the kick if you googled 'butterfly kick'. Collin Chou uses it a lot in his movies.

-Donnie out
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I got two fists.. Don't make me use my head as well!