Well, if you're playing on rookie/pilot level, use the swordfish and if you're playing in ace, use the beaufighter.
First, sink the abandoned freighter using torpedos.
Then, sink that destroyer(keep the torpedo ready, as in speed and altitude before the cut scene and fire it immediately after the cut scene, this way, you won't be facing a lot of fighters).
Next, you'll find the gneisenau, better approach the ship from the right side to avoid a destroyer, torpedo it and hit warspeed and try avoiding the flak.
Give it a good 2-3 hits before the bonus objectives show up(Note: If you're playing in rookie, hit her JUST once and then wait for sometime for the bonus objectives to become available).
Ace or chain kill all the stukas, you don't have enough time to gain altitude for both the waves.
Return back to the gneisenau and finish her off in the same way described above.
Next move towards the sun using warspeed until the E-boats around SS Ariel get lit up and then zero on to them. Use the cycle button 'C' to switch from torpedos to rockets, aim and fire, Note that rockets aren't as fast and accurate as bullets.
Next, find the Scharnhorst and Prinz Eugnen, you can recognize them by search lights and two silhouettes of battle ships next to them. Sink the destroyer without getting too close(without activating the cut scene).
Then sink the battleships with same deploy torpedo and zip away using warspeed tactics.
There'll be utter chaos but just focus and maintain your speed properly.