function jetpacks(event) {
    event.remove({ mod: 'ironjetpacks' })
    event.remove({ id: /ironjetpacks:.*/ })
    event.remove({ mod: 'mekanism', output: /mekanism:.*jetpack.*/ })
    event.remove({ output: MEK('module_jetopack_unit') })

    function capacitor(tier) {
        event.shaped(Item.of('ironjetpacks:capacitor', `{Id:"ironjetpacks:${tier}"}`), [
            'MMM',
            'EEE',
            'MMM'
        ], {
            M: F(`#ingots/${tier}`)
        })
    }

    capacitor('iron')
    event.shaped(Item.of('ironjetpacks:jetpack', '{Id:"ironjetpacks:iron",Throttle:1.0d}'), [
        'SCS',
        'MBM',
        ' M '
    ], {
        S: 'create_dd:steel_ingot',
        C: MEK('basic_control_circuit'),
        M: MC('iron_ingot'),
        B: Item.of('ironjetpacks:cell', '{Id:"ironjetpacks:iron"}')
    })

    function tier(previous_tier, tier, control_circuit) {
        capacitor(tier)

        event.shaped(Item.of('ironjetpacks:jetpack', `{Id:"ironjetpacks:${tier}",Throttle:1.0d}`), [
            'MCM',
            'MJM',
            'MBM'
        ], {
            M: F(`#ingots/${tier}`),
            C: control_circuit,
            J: Item.of('ironjetpacks:jetpack', `{Id:"ironjetpacks:${previous_tier}",Throttle:1.0d}`),
            B: Item.of('ironjetpacks:capacitor', `{Id:"ironjetpacks:${tier}"}`)
        })
    }

    tier('iron', 'steel', MEK('advanced_control_circuit'))
    tier('steel', 'diamond', MEK('elite_control_circuit'))
    tier('diamond', 'emerald', MEK('ultimate_control_circuit'))
}