Having read the Nicassar Caravan section of BFG 2010 FAQ I'm wondering how one determines the aspect of a target.
I've test fitted Dhows to a Tau orbital and they are too long to be attached parallel to the arms of the modules. This makes it impossible for all four Dhows to face in the same direction of travel. They can be mounted with opposite pairs facing in the same direction, which gives two pairs pointing at 90 degrees to each other, or with all four Dhows facing in different directions as if circling the core module.
Given that situation and the ability of the Caravan as a whole to move in any direction, how do you decide if a target is closing or abeam?