Blueprint Intel

Blueprints are organized into 3 tiers, which are as follows:

Tier 1 - 7 weapons/2 advanced, 32/8 pieces:

Impact Cannon D30-N and L
Assault Cannon D33-X
Strike Missile D51-N, L, A
Firestorm Rockets D91-N

Small Cargo Hold
Hull Streamlining I

Tier 2 - 12 weapons/2 advanced, 67/10 pieces:

Impact Cannon D30-A
Assault Cannon D33-P and A
Siege Cannon D35-S
Assault Missile D53-C, M and R
Shockwave Mortar D71-N, L and A
Firestorm Rockets D91-L and A

Medium Cargo Hold
Hull Streamlining II

Tier 3 - 17 weapons/2 advanced, 123/12 pieces:

Siege Cannon D35-L and X
Siege Missile D55-A, E and V
Assault Mortar D73-C, M and R
Assault Rockets D93-C, M and R
Siege Mortar D75-S, V and D
Siege Rockets D95-F, W and D

Large Cargo Hold
Hull Streamlining III

In general, blueprints in Tier 1 are dropped by lvl 4 and 5 salvages (Drac fleets lvl 16-23), Tier 2 bps by lvl 6 and 7 salvs (Drac fleets lvl 24-31), Tier 3 bps by salvs lvl 8 and above (Drac fleets lvl 32+). However, when you do not have all blueprints for a given tier completed, salvages designed to drop higher level bps will also drop bps for the incomplete lower tier. Hence you should, for example, try to finish all Tier 2 prints before attacking lvl 8 salvs, in order to ensure they really will drop Tier 3 bps and not something you will get with much more ease from a lvl 6 salv.

With the new, improved spawning correlation in effect since the Revenge Raid II, salvs lvl 4 spawn next to players lvl (pl) 12-15, lvl 5 pl 16-19, lvl 6 pl 20-23, lvl 7 pl 24-27, salvs lvl 8 pl 28-31, lvl 9 pl 32-35. (Note that there can only be a certain number of salvs in any given space, so lower-lvl salvs of neighbours can block yours from spawning.) Mines lvl 6 are identical to salvs lvl 4, mines lvl 7 = salv lvl 5 and so on, with one exception: The lvl 10 Zynth mines now have an updated Drac fleet identical to a lvl 8 salv, however the fleet's lvl is still displayed as 30, not 32, therefore it will not yield Tier 3 bps.

Now it is important to know that you can only have 4 blueprints of each tier in the works at once. Meaning once you have found pieces for 4 weapons of one tier, you will not find pieces for a new weapon in this tier before you have completed one of the 4 already discovered. Note that you can have more than 4 uncompleted bps at once if they belong to different tiers. Once you discover the final piece of a Drac weapon, the next blueprint you find will almost always be the first part for a new weapon.