Heavy 1

Information

Weapon slot 1 Spinfusor This is my favorite combination. It's a kind of all-round unit. Best on indoor fighting but can also be tailgunner or support. Less effective on outdoor fighting if your not very skilled with the chaingun.
Weapon slot 2 Chaingun 
Weapon slot 3 Grenade Launcher
Weapon slot 4 Missile Launcher
Weapon slot 5 Fusion Mortar
Pack Shield
Grenade Flare Grenade
Mines Yes

 

Heavy 2

Information

Weapon slot 1 Spinfusor This is specialized on indoor fighting. The concussion grenades are extremely good to get a big advantage over your enemies, use them carefully. 
Weapon slot 2 Chaingun
Weapon slot 3 Grenade Launcher
Weapon slot 4 Plasma Rifle
Weapon slot 5 Fusion Mortar
Pack Shield
Grenade Concussion Grenade
Mines Yes

 

Heavy 3

Information

Weapon slot 1 Spinfusor The perfect tailgunner. Use on Thunderswords or transports. Repair while you are in the air, throw flare grenades, fire missiles on enemy aircraft.
Weapon slot 2 Chaingun 
Weapon slot 3 Grenade Launcher
Weapon slot 4 Missile Launcher
Weapon slot 5 Fusion Mortar
Pack Repair
Grenade Flare Grenade
Mines Yes