You will need to use the Trax editor, it's a fairly simple concept to create non-linear animation, select your object with the animation on, go to the Animation menu set, 'character' > 'create character set'. You will be able to see the new character set in the outliner. Now open up your Trax editor with the new set selected, it should pop up in the Trax, if not you may have to go 'list' > 'auto load selected character'. Now select your object wit the animation on and in the trax editor go to 'create' >'animation clip'. Set the options to whatever you need, You will now have a 'clip' of your floating up animation. You can now cycle it in the attribute editor, check the help files for more info on all the stuff you can do with the Trax editor.

Hope it helps

Chris