Todjaeger
Potstirrer
A non-nuclear submarine is not particularly good at intercepting anything, AIP or not. The generally published max speed of current diesel-electric subs is ~20 kts submerged, however that is not a speed which can be sustained for any length of time.I know SSNs are around 2.5 billion and the odds of getting them are nil but AIP can only sustain for a month at max and I'm pretty sure that means not moving around. An SSK on AIP means running at a max speed of 5 knots. Not great for intercepting.
I thought maybe a snorkel alone could punch through the ice somehow at least as a backup to AIP in case it fails.
Depending on the design, AIP can provide sufficient power for 2-3 weeks of operation at low speeds. IIRC that was sufficient for a Germany sub to transit from the North Sea into the Med remaining submerged, which took approximately three weeks. Looking at the numbers, that would suggest an average speed of ~4 kts.
What people again seem to be over looking is that while AIP is all nice and everything, just how much power can it generate when needed?
Part of the reason why the RAN trialed AIP Stirling engines, but did not adopt them on the Collins-class SSG is that they would have added too much weight, and occupied too much space for the amount of air independent power generation they would have provided. The space, weight and internal volume that AIP and their fuel systems take up typically reduce the amount of available space and weight for batteries, diesel generators, and fuel bunkerage. Having the ability to run a 2-3 week trickle charge is nice, but also useless if frequent large power spikes are required. Those requirements are dictated by a sub's sensor and combat data system fitout.
-Cheers