on leftclick:
    player is wearing {leatherjetpack}
    thrust player upwards at speed 0.4
    thrust player forwards at speed 0.1
    show mob spawner flames at location of the player
    damage player's chestplate by 1 heart

command /jetpack:
    permission message: &8[&6&lJetpack&8] &eYou do not have permission to use &6Jetpack
    permission: jetpack.leather
    trigger:
    set {leatherjetpack} to leather chestplate named "&8[&6&lJetpack &7&o(Use at your own will)"
    give {leatherjetpack} to the player

on rightclick on a sign:
    if line 1 is "[Jetpack]"
    if line 2 is "repair"
    if player is holding coal
    player is wearing {leatherjetpack}
    repair chestplate of player by 3
    remove coal from player