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Assuming that your question does not concern situations like the AN70 where there is so much power for the prop to absorb that both props need to be as large and solid as possible, what we are looking for is the most efficient thrust distribution through the prop disc. You want a smooth distribution as you would for a wing. The thrust developed on a rotating ...


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Without knowing more about what you are designing it is impossible to come up with a specific number. But there are a number of factors that you should take into account: the lower the thrust to weight ratio, the longer it will take to accelerate, so the longer the required runway will be. During the take-off roll the lift can usually be neglected, but the ...


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Why not make 94.5% read as 100%? 94.5% tells you the margin you have. It will be closer to 100% in high-thrust versions – or even higher, i.e. the limit is pushed as the thrust ratings increase. The PW1100G you're asking about, its thrust varies from 110 to 150 kN based on the installed version. For example, the A321's 150 kN CFM56-5B3 exceeds 100% near sea ...


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The thing you are missing is that for a jet engine, there is no fixed relationship between rotor speed and thrust. For a given speed, the thrust depends on altitude and air temperature. Therefore, there are separate limits on engine operation for maximum thrust and maximum rotor speeds. If you are at a "hot and high" airfield like Nairobi (say 30C ...


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MCP is maximum power that can be used indefinitely without shortening the life of the engine. You might use MCP when you need all the available power during single engine cruise, to maintain an altitude for obstacle clearance, or when climbing single engine. MTOP is normal maximum for takeoff and initial climb, with a time limit. If you exceed the time ...


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Aviation is an exercise in mitigating risks. There's usually more than one hazard at any given time. So, yes, running your engine at full power might increase risk of engine failure versus a lower power setting. However, taking off at lower power settings increases risks in other areas. For instance ... ... you have to reach rotation speed before you go ...


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Because Runways Are Short (relatively speaking) The simple answer comes down to the fact that you only have so much space to take off so getting off the ground as fast as possible is the most practical and most safe option. Aircraft will fly when the wings generate sufficient lift to overcome the weight of the aircraft, this happens when there is enough ...


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It should come as no surprise that flying an airplane is not like driving a car. When driving a car, you can come to a complete stop and nothing exciting will happen. You cannot do this in an airplane; coming to a complete stop is either the beginning or the end of a great deal of excitement. Flying near the ground in any circumstance is a hazard. As you say,...


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