Cross Site answer by Valorum at Science Fiction & Fantasy who said....
I initially thought Skynet might be strapping them onto Hunter-killers.
But on rewatching the episode a second time, I realised that we do actually see them again. Skynet has turned several of them upright in order to power its Time-Displacement Equipment (TDE).
With correct gearing, a 6000rpm jet engine converted into a makeshift electricity generator could easily produce between 250-300Kw. Six of them in series could generate in the order of 1-2 megawatts of power on demand. Not the most elegant of solutions (noisy, breakable), but then Skynet was getting pretty desperate by this point and evidently needed to build the TDE at short notice, unlike other timelines where it was able to custom-build and dedicate an entire facility to the TDE chamber.