Gravity and how it works—or doesn't work—can cause all sorts of arguments in a game.
If you've set up a clever trap or area of interest where the gravity is reversed or sideways or non-existent something, and players want to complain that gravity can't possibly work that way, just tell them you're using general relativistic gravity, not Newtonian gravity. Anyone with less than a degree in physics should hopefully be too bamboozled to argue further.
And if you do happen to be playing with players who have degrees in physics, just tell them you're using Aristotelian gravity, not Newtonian or relativistic gravity. That'll shut 'em up.
Commentary by memnarch (who has not seen the movie)
That must be a strong gravitational field for the ship to go down that fast, but Jim would know astrophysics better than I do. Personally, I would have guessed that the various compounds and escaping gases violently expanding only made it look like it was going down. Or if remaining bits of the bomber are actually going through the explosion, the anti-grav generators are no longer properly balanced and are pushing the ship debris down before they give out.
This whole scene, from the start when the destroyers pop out of hyperspace to whenever this finishes up, feels like the sort of thing Star Wars fans would talk about quite a bit once the movie was out. I can imagine lots of back-and-forth about things like "Why didn't the B-wing-like ships do this?" or "Why not have more ships equipped with that super engine Allan used?".
Hmmmmm. Looking over the exploding ship again in panel 2, I think that that bit on the tail is yet another ball turret. So now it seems a lot more likely that these are intended to be a different kind of ship instead of a changed B-wing, and most likely a proper bomber-type ship as well. Which just means that now I'm wondering why aren't they trying to shoot the incoming TIE fighters. I'd hope that the ball turrets aren't just for show, but I'm not that impressed with the amount of red plasma bolts I'm seeing from the Resistance side at the moment. The B-17 Bomber I linked a couple commentaries ago that I was reminded of wasn't called the "Flying Fortress" because it ignored all the enemies flying around it.
[SFX]: pow! pow! pow!
[SFX]: Pow! Pow!
GM: <roll> A bomber is hit and goes down in flames!
Paige: Why would it go down? We’re in orbit.
GM: That was a metaph—
Allan: We’re obviously hovering in low-altitude space, not orbiting. D’Qar will pull down anything without anti-grav capability.
Paige: Fair enough.
Captain Canady: Recharge auto-cannons! Target their cruiser, eh?
BB-8: Tallie! They’re targeting the fleet!
Tallie: I see it. Bombers, begin drop sequence!
GM: You’re dropping bombs in space?
Tallie: Jim just explained the gravitational dynamics of your setup. Is there a problem?
GM: Uh, no. Carry on.