Running Ad Astra and Entity Culling causes the back half of the rocket to be culled while sitting inside the rocket, even when viewing it in third person. An easy fix is adding the lines

"ad_astra:tier_1_rocket",
"ad_astra:tier_2_rocket",
"ad_astra:tier_3_rocket",
"ad_astra:tier_4_rocket"

to the config.
Perhaps in a future update these can be added to the config by default just like the botania and create blocks present in the config already.

Edit: It appears I was mistaken. Adding these lines to the config does nothing, it only renders correctly at very specific third person camera angles. I tried adding the lines to both blockEntityWhitelist and entityWhitelist but no dice. So I guess this is now a bug report rather than a feature request.

Uhhh did you test that it's EntityCulling at all? Because that description and your results seems more to suggest that something else is going on.