Ballockets Ad Parietem - or if it must be Latin only...
Aerostati Ad Parietem (literally "balloons to the wall")
or (the only usable attempt to create a Latin portmanteau word):
Pilacendii Ad Parietem
combining "pila" (ball - also a possible translation of balloon per several sources) with the plural of "incendium" (an incendiary missile).
Of course, while I intended pilacendii to be equivalent to ballocket, it probably is closer to "flaming flying balls", which might make even a brave Playmonaut pilot uncomfortable.
The most common translations of "balloon" were "aerostatum" (airship, hot-air balloon) and "vesica" (balloon or bladder, but not necessarily something intended to rise). I found no good translation of "rocket" except as salad. "Rucheta" appears related to architecture or surveying, and Google's "fusce" is apparently wrong, even according to Google when re-translated to English.
Someone who actually knows Latin could probably do better, and is likely snickering at my ignorance... 8-}