Ah yes, Ark's swordfishes mistook Sheffield for Bismarck and launched ELEVEN torps at her. Sheffie was saved by a combination of luck (faulty magnetic exploders causing some torps to prematurely detonate in the water) and extremely skillful maneuvering on the part of her crew. Epic torpedobeats, basically.
Turned out to be a blessing in disguise too (well, not for Bismarck), since the friendly-fire incident revealed the faultiness of the exploders so they swapped back to the older contact ones instead for the attack on Bismarck. And the rest was, well, history.
Movie depiction starting here, from Sink the Bismarck!(1960).
To be fair for Ark Royal's air complement, they weren't aware that Sheffie was operating in the area (the admiral basically detached Sheffield from the fleet to shadow Bismarck... WITHOUT informing Ark Royal of the fact.). As far as they knew, there was only one ship in that general area, which was the Bismarck. Weather and visibility was also quite poor, and IIRC the leading swordfish had to rely on ASV radar.
Have they done an event based on the Bismarck Affair yet? Because it seems like there's still a lot of ships from it they could add (Hood, Rodney, Piorun...)
The next op! You'll be needing a carrier, won't you!But the unchanging one has come....times sure have changed.I have no idea who you are, but please save me!Hmpf.At that time, Ark Royal's flying corps misidentified her and sent some attacks her way.Wha!?BISMAAAARCK!!For us to be escorting a transport convoy of the old Allied nations...NOOOOOO!Ark's chasing after her, so that means she's...!Sheffield also took part in the attack on Bismarck in her previous life.BISMARCK!?I'm going with Graf!We're comrades-in-arms, aren't we!?Team up with me, and...Don't be such a downer!