Yeah, this is Forced Entry. Notoriously tricky
It shouldn't vary by difficulty level - the key is being in position in time.
Just make sure you have at least four (preferaby more) Trebuchets ready at the end of the mission. Don't use them earlier. As soon as the Temeraire jumps in, order all your ships to defend it, afterburn as fast as possible to the Temeraire, keep burning past it.
As soon as the Abel jumps in, lock on to one of the forward beams (use 'v' to target the turret under your reticle) and fire two Trebuchets at it. Then lock onto the other forward beam and Trebuchet it as well.
It might pay off to take out the two rear stinger beams as well. Use your remaining Trebuchets and primaries to do that.
The only other thing I usually Trebuchet in this mission is the main beam on the Lilith that jumps in.
Forced Entry is a really awesome mission (especially because of the music), but it's extremely unforgiving.