Yeah, the Glaive beam is one of those gadgets … if it works, it’s awesome. If it doesn’t … not so much.

The beam isn’t working in this case, because the enemy is throwing stuff at you faster than your beam can load and your ship can tank. One possible way to salvage this situation could have been to turn off the beam, reorder the weapons and use the ion blast and basic lasers to work your way through the enemy shield towards their weapons bay.