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The principles of flight dynamics are used to model a vehicle's powered flight during launch from the Earth; a spacecraft's orbital flight; maneuvers to change orbit; translunar and interplanetary flight; launch from and landing on a celestial body, with or without an atmosphere; entry through the atmosphere of the Earth or other celestial body ...
"Sky Lift" is a science fiction short story by Robert A. Heinlein, first published 1953. In the story, a torchship pilot lights out from Earth orbit to Pluto on a mission to deliver a cure to a plague ravaging a research station. [12] Tau Zero, a hard science fiction novel by Poul Anderson, has a spaceship using a constant acceleration drive.
Since the Oberth maneuver happens in a very limited time (while still at low altitude), to generate a high impulse the engine necessarily needs to achieve high thrust (impulse is by definition the time multiplied by thrust). Thus the Oberth effect is far less useful for low-thrust engines, such as ion thrusters.
White's team attempted to model the thermal effect on the overall displacement by using a superposition of the displacements caused by "thermal effects" and "impulsive thrust" with White saying "That was the thing we worked the hardest to understand and put in a box".
Propeller walk (also known as propeller effect, wheeling effect, paddle wheel effect, asymmetric thrust, asymmetric blade effect, transverse thrust, prop walk) is the term for a propeller's tendency to rotate about a vertical axis (also known as yaw motion). The rotation is in addition to the forward or backward acceleration.
Thrust power is the speed multiplied by the drag, is obtained from the lift-to-drag ratio: =; here Wg is the weight (force in newtons, if W is the mass in kilograms); g is standard gravity (its exact value varies, but it averages 9.81 m/s 2).
When in flight, the main or major forces acting on the projectile are gravity, drag, and if present, wind; if in powered flight, thrust; and if guided, the forces imparted by the control surfaces. In small arms external ballistics applications, gravity imparts a downward acceleration on the projectile, causing it to drop from the line-of-sight.
Unlike using a thrust-impulse to instantaneously change the velocity of the spacecraft, in non-impulsive transfer, there is a continuous application of thrust, so that, the spacecraft changes its direction gradually. Non-impulsive transfers relies on the low-thrust propulsion for the operation.