Ballistic NG - Wipeout fan project

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Originally Posted by amplificated

The airbrakes seem like they give you sideways momentum in the opposite direction of the side you're braking on in addition to slowing you down generally, which seems the opposite of intuition...

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Actually, Newton's first law would disagree with you. The airbrakes only add a torque to the ship. Torque itself doesn't affect the ship's linear momentum, what makes the ship move in the same direction is the engine, but since your initial velocity to that new direction is zero, the ship has to accelerate to effectively move in that new direction. This happens a lot in planes, that's why maneuvers like this and this work.

In any case, the reason the airbrakes do that is due to the game being based on the early wipeout games.

Other than the claim about Newton disagreeing with me, I generally agree with you... but you didn't explain why the ship moves in the opposite direction the brakes are being applied to when the initial vector is straight, and I can't see it happening in those videos. In fact, the manoeuvres in both videos appear to have nothing to do with lateral movements of any kind...

For the record, the 1st law IIRC is that an object in motion will tend to stay in motion. So if I'm going straight, why do I go left when I turn right? I'm not following you here.

I haven't played the originals extensively, but I've played them a bit, and I feel a lot more comfortable after a few minutes in them than I do in BNG... and I haven't noticed this phenomenon there. I feel I can swing my craft around in WO3, but in BNG, I just don't have that amount of control in corners.

Oh you mean when going straight, I thought you were talking about the drifting when turning.

I think that's just a programming quirk, but in fact it can also be physically explained by Newton's third law, but this will require some drawings to understand better, since it depends on the geometry of the airbrakes.

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So, Newton's third law says that for every action there's an equal and opposite reaction. In this case the force the airbrake exerts on the air particles creates an opposite reaction force on the airbrake, and since that's connected to the ship, the ship feels the deceleration+a sideways push to the side opposite to the airbrake used.

The difference is that in the original Wipeouts using only the airbrakes made the ship turn to the desired direction albeit very slowly, but there was no sideways drift.

You're reaching :P

Even if what you're showing in that diagram were the case, the direction the nose is pointing is not straight, the airbrake turns you right (if you're holding right ab) - so that momentum would shift rapidly in the direction you were originally heading, if it even existed at all. I'm not going to claim I'm an aerodynamics expert, and from my understanding it's a ****ing complex field, so I'm assuming none of us are.

I just feel the current setup is unintuitive. Check it out. Ramp on Ishtar.

Before the rotation speed starts being noticeable, that's what will happen. How fast the ship starts turning while drifting depends a lot on its mass. So in heavier ships this is what you'll see happenning, pretty obviously. I'm certainly not reaching, I have at least a year's worth of fluid dynamics in my physics engineering degree ;)
In any case, as the ship turns it will still drift sideways to the direction opposite to the airbrake being used. The aerodynamic drag force is very high at very high speeds (increases with the speed squared), so this effect will have the biggest impact just before the ship starts turning. It doesn't mean the force is constant during the use of the airbrake, but the first impulse is enough to send the ship drifting sideways a bit.

Of course, this is just an explanation to what would actually happen IRL. What happens in BNG is just a programming quirk on the physics engine.

I forgot to add (tired), but I think you're forgetting that the accelerator is still being held all this time... so the ship is facing e.g. perpendicular to the track, and it's still going the opposite direction.

Well yes, we're talking about a jet (thrust) engine, it doesn't have an immediate response to a change in direction, like a car. If you have an object moving, say, left, at a constant speed, and you add a thrust perpendicular to that direction, the object will start accelerating in that perpendicular direction BUT it maintains its momentum to the left regardless, Newton's first law.

But we weren't heading left ;)

I don't understand what you mean. Plus I already said the ship behaviour in BNG is a programming quirk.

Forgive me, it's 4am. Finally lost it I think. GG

And yeah, I always assumed it was a programming quirk. It's just one I don't have a particular fondness for! -_-