The Eagle long range fighter was the starting ship in Elite 2: Frontier released many years ago. For Elite Dangerous, the Eagle is the first combat ship available. From a Sidewinder, the Eagle is faster and mounts an additional class 2 weapon mount.
I have found the energy usage of energy weapons is very high and therefore with 3 mounts you will need to look towards either low energy weapons or weapons that do not require energy at all. My configuration for the Eagle as based around 2 x Class fixed multicannons and a class 1 gimballed pulse laser/class 2 fixed pulse laser. These were then organised into primary and secondary fire groups where the multicannons are used once the shields are stripped from the target. Against npc fighters, the energy weapon draws the attention of the target and when they begin their attack, I use all weapons with sustained fire to quickly damage/destroy the target.
1x Utility Mount[s]
3x Small Hardpoint[s]
1 x Size 1 Internal compartment[s]
1 x Size 2 Internal compartment[s]
1 x Size 3 Internal compartment[s]
Fuel Store (Default):
Fuel Capacity: 4
Internal Compartments (Default):
Cargo Rack Capacity 2
Basic Discovery Scanner
Checked: Beta 3.03