Parachutes were a very cool feature to have on a server. The plugin I used to use can be found here: http://dev.bukkit.org/bukkit-plugins/skydiver/ Since this plugin is outdated and has no source code, it has to be completely remade. If someone was willing to tackle on this project I'd be delighted. May even throw some dosh your way in the end. Thanks for your consideration
There's no errors, but what happens is when users use the parachute, when they land they have creative flying. So pretty much the plugin doesn't make the creative flying boolean false after they land.