IT's actually very simple to reproduce, go to any accelerator that has an L ship going through it, and watch IS. The L ship will often times appear in the very middle of the gateway when it arrives, and anything coming behind will crash into it. To prove this, I started watching the gates and making saves before each crash event occurred. I also reload the save again to verify it happens again.
So I've been camping gates and just waiting for it to happen, and now I have compiled a list of saves where a collision event happens. Sometimes they will boost and lose all its shields on entry, but I'm not sure why it doesnt do it 100% of the time, you can reproduce this though if you reload a save enough times
1. Heron E goes through gate, then gets crashed into shortly after. You'll be aboard the Heron E before it goes through the accelerator gate, and will have to wait <20 seconds or so.
https://www.dropbox.com/scl/fi/2iynlx1i ... ozacm&dl=0
2. Two Argon Freighters crash into each other (one loses near 50% health) - this one happens very early in the save, you should PAUSE immediately when loading and look at CLV-521 and BRP-953. The crash will not happen if OOS (Which you are in the current save), so you should switch to external view on one of the ships before they arrive.
https://www.dropbox.com/scl/fi/268e82wn ... bxn68&dl=0
3. Two Magnetars crash into each other
In this save, you will be onboard a magnetar, this is like the first, you'll have to wait for it to go through the gate, once it goes through the gate, another magnetar slams right into it's rear.
https://www.dropbox.com/scl/fi/ch4guiwc ... e45it&dl=0
4. Crane crashes into Heron E
In this save, the Teladi Heron E (IWL-644) will be jumping from accelerator gate to Grand Exchange I. When you load, you will be on a nearby station from where the IWL-644 will arrive. Once it arrives, watch the IWL-644 in external view, in about 15-20 seconds or so - a crane will crash into it. it happens right when its travel drive sounds like its about to fully engage.
https://www.dropbox.com/scl/fi/0efgvdbj ... nwf1q&dl=0
Let me know if you need any more saves capturing this behavior. I think the issue is that L Ships arrive in the middle of the accelerator and they take up almost the entire area of it. In addition, they are slow. So the more L ships are going to pass through an accelerator within a 30 second window, the more likely they will crash into each other.
I only spent about 30 minutes carefully watching gates and capturing them, and there were even a few I just was too slow to capture. You have to save before one goes through the gate, and make sure it arrives in high attention. But honestly, if you have L ships passing through acceleration gates in high attention, a collision is highly likely to occur.
I only spent time watching grand exchange, but want to mention the acceleration gate at Iunumus Zura (next to the trading station) is another common area where you'll find them.
I can capture more, just let me know if these saves are good enough or if there's some more data that is required to track down the issue.