I actually had a similar incident just recently too. I was sailing around in the area to the SW of Manilla, in a monster of a typhoon no less, at 1024x. And my watch officer reports ships spotted, so I scury on up to the bridge to take a peek.
At first I thought he was seeing things as I couldn't see a darn thing due too the weather, and it being pitch black out. But just as I was about to order a dive to PD to check for contacts, I literally jumped out of my seat when I spot a Takao CA sail on by at less than a 80 yrds to starboard.
I was so supprised that I completely forgot about diving, and just sat there and watched, as we camly passed by each other as two ships in the night (literally lol). Anyways, shortly after the Takao heads off into the stormy gloom, I spot another object, and another, and then a third, heading strait towards me same as the Takao. Wasn't long before I realised that I had two Shokaku CVs and a Furataka passing by right to my portside, in what would have otherwise been a picture perfect attack position.
But, as the saying goes, if its too good to be true, well it probably is. I just happened to have spent my last six torpedoes on a large tanker just earlier that day.
There's nothing more frustrating than to be torpless while a task force steams right in front of you.
Oh, did I mention I love this game.