So I wrote this up for someone else but since people are asking about how to fly with the g-safe off, I figured in attention to how negative pressure works I would post how a turbine moves a craft forward. Most people can tell you that the engine goes on and the craft moves forward. This explains how scientists see it. premise you have to have more vacuum in front than behind to create forward movement. The suction of a turbine spinning with the blades straked to blow the air to the rear, creates vacuum in front of the craft. Straked just means the angle of the fan blade. Pebbles in the river or drag is created by anything that bisects the flow of fluid through the craft is traveling. This creates vacuum behind the craft pulling it downstream. Much like log jams eventually break loose in a flash flood or during a controlled flood release on the Colorado river. So you have your drag on one side of the equation and the F = P/A created by the force of the fluid being pulled though the turbine. More vacuum ahead of the craft the craft moves toward the larger amount of vacuum, that it has contact with. More drag that thrust the craft moves backwards to the direction of the parts being pulled on my drag. The short is that it is a fan that tries to bring the fluid or air in front of a craft into the turbine inside the body of the craft through the intakes and compress it by sucking in air faster than it exits the craft's afterburner mouth. So just remember that the more space the shape displaces the more fluid that has to enter the intakes faster than the space displaces. Or basically the craft has to suck the volume of the craft in fluid though the intakes faster than it travels forward through space. The force created behind the craft pushes on the force that exits a second before as the faster the craft moves the faster the air behind it needs to fill the space behind it with more pressure than the force further out can dilute into the space around it.