To the OP I am not suggesting that you are not having a problem but it is not a consistent problem.
It's a consistent problem for any ship with low/ no shields. Also security will boost at stations and collide for exactly the same reason; NPCs attempt to close distance to institute a scan and will happily plough into you to achieve this goal because whatever routine is in place to scan, appears to be at a higher priority to collision avoidance.
And all NPCs, regardless of mass will only attempt to stop, once they are within the 1km scan range. This is automatically problematic for all ships based on the FDS hull & Anaconda, as they are incapable of stopping within 1km of a target at maximum cruise velocity (let alone boost) and to a lesser degree Clipper.
Having said that even Eagles and Vipers will bounce off the hull. You can often hear them coming in, with throttles at full. There's no hint that they are in the process of avoidance. It is plausible that this is latency dependant, and anyone who is on a more latent connection to the ED servers, is automatically at a higher chance of collision due to the inherent delay this could cause.
But come on. An eagle? It has arguably the best acceleration, deceleration and agility stats in the game. I can forgive a lumbering Anaconda for being a bit crap at avoidance, but vipers and eagles have no excuse. AI, go home, you're drunk.
This is a known issue, it's something frontier are aware of. Note that I don't really care if the NPCs don't slow down; just that their intercept routine needs some work so they apply pitch, or some other thruster input to at least attempt collision avoidance. A direct intercept (you can actually maneuver and observe the AI react and also maneuver to
ensure they collide) such as in place now, is busted and needs a bit of work.
Hell, simply adding some 'fuzz' to the intercept routine means they would more often than not zip past, rather than outright collide. Right now, AI is arguably more accurate than a Tomahawk Cruise Missile.