First off, I'd suggest you ditch the Boanerges and equip your entire wing with Ursas. This gives you a chance whenever the enemy fighters decide to pay you a visit, as the Ursa turret is equipped with a Kayser and will auto-track your current target, making up for your lack of maneuverability (something which, surprisingly, makes the Ursa one of the easiest ships in the game to kill Dragons with).
Second, pay attention to which fighters are actually interested in you, and take those out. Most of them are going after your allied capital ships, and those you can safely ignore for as long as they have other targets to deal with. Unless you've changed the binding, the 'R' key will target the nearest ship attacking you.
Third, attack the Ravana from a direction where it can't shoot you. Approaching it head-on is one possibility
Fourth, use your wingmen wisely. Don't just tell them to attack and forget about them, form them up, fly them to the place you want to attack from, and then order them in. And make sure to let them go first so they can catch any stray fire that might come your way while you're making your own run
