Not everything needs to be a single sentence. "The tank of hydraulic fluid ran out before landing. This tank powered the fins that steer the rocket. Therefore the rocket could no longer be steered."
Or there's the ablative: "The tank of hydraulic fluid having been emptied, the fins could no longer steer the rocket."
I'd argue that's because it's wrong; not massively wrong, but wrong. You can have a parenthesis with commata on both sides (as siblings have suggested), or you can (just) write the same sentence with no commata at all and it would make sense, but a single comma in that position is a mistake.
Where's the passive? "The tank ... ran out of fluid" isn't passive. (If it is, then "the heroes ran out of time", "the car ran out of gas", "I ran out of money" and "the airplane ran out of runway" also use passive voice, yes? What is the active equivalent?)
"hydraulic fluid that powered the fins enabling them to rotate and steer" isn't passive either. Poorly written, certainly.
I double-checked with the examples in http://www.lel.ed.ac.uk/~gpullum/passive_loathing.pdf and still didn't see a match. FWIW, that paper also comments "mistaken charges of using the passive voice are commonplace".
My apologies, I read 'to rotate' as passive but it isn't at second pass. I should have tried rewriting it as active voice and it would have become obvious when I failed.
The tank filled with hydraulic fluid, powering the fins and enabling them to rotate and steer, ran out of fluid before landing.
Hopefully the above reads more clearly. It is how I parsed it on first read.