What is the difference between ATA and DATA entries?

ATA is supposed to indicate the unloaded air to air maneuverability whereas DATA is supposed to be more about loaded maneuverability (hence also seeing it in the loadouts annex).  For the next build (2024.001 ETA TBD) I've fixed a few bugs in this area thanks to your posting.

Hello, there is something that isn´t clear to me.

When an aircraft or missile reaches 1000 knots or more you get a bonus to DATA.

Is it of 30% as in Harpoon 2 paper rules?

Is it of 10% as in Harpoon 4 paper rules?

I have read somewhere that HUCE is based on Harpoon 3 paper rules. So I don't know of how much is this bonus.

30% as per the Harpoon 3 paper rules 6.2.1.1

if (tUnit->kts > 1300L)
  ProbHit -=30; / *fast mod */