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The thrust-to-weight ratio of a rocket improves as the propellant is burned. With constant thrust, the maximum ratio (maximum acceleration of the vehicle) is achieved just before the propellant is fully consumed. Each rocket has a characteristic thrust-to-weight curve, or acceleration curve, not just a scalar quantity.
The low speed region of flight is known as the "back of the power curve" or "behind the power curve" [7] [8] (sometimes "back of the drag curve") where more thrust is required to sustain flight at lower speeds. It is an inefficient region of flight because a decrease in speed requires increased thrust and a resultant increase in fuel consumption.
A rocket's required mass ratio as a function of effective exhaust velocity ratio. The classical rocket equation, or ideal rocket equation is a mathematical equation that describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself using thrust by expelling part of its mass with high velocity and can thereby move due to the ...
A thrust curve, sometimes known as a "performance curve" or "thrust profile" is a graph of the thrust of an engine or motor, (usually a rocket) with respect to time. [1] [2] Most engines do not produce linear thrust (thrust which increases at a constant rate with time). Instead, they produce a curve of some type, where thrust will slowly rise ...
Thrust is the force supplied by the engine and depends on the propellant mass flow through the engine. Specific impulse measures the thrust per propellant mass flow. Thrust and specific impulse are related by the design and propellants of the engine in question, but this relationship is tenuous: in most cases, high thrust and high specific ...
If a powered aircraft is generating thrust T and experiencing drag D, the difference between the two, T − D, is termed the excess thrust. The instantaneous performance of the aircraft is mostly dependent on the excess thrust. Excess thrust is a vector and is determined as the vector difference between the thrust vector and the drag vector.
The calculation is somewhat different for reciprocating and turboprop engines which rely on a propeller for propulsion since their output is typically expressed in terms of power rather than thrust. The equation for heat added per unit time, Q , can be adopted as follows:
The particular take-off distance required may be shorter than the available runway length. In this case a lower thrust may be used. Lower thrust settings increase engine life and reduce maintenance costs. The take-off thrust available from a civil engine is a constant value up to a particular ambient temperature.