Read about rocketry | 10 Discussions | Page 1

  1. Robert DeVries

    Trouble with fluid thermodynamics and nuclear thermal rockets

    Summary:: In need of help determining the exhaust velocity of a rocket nozzle given temperature and propellant molar mass Greetings and salutations! My name is Robert DeVries, world builder extraordinaire. I have come with questions in search of answers. So for the last few days I've been...
  2. Physyx

    How to model a rocket equation from the derivative of momentum?

    I am using the derivative of momentum (dp/dt) with Newton’s 3rd Law with the gravitational force of Earth. F - [Force of gravity on rocket] = dp/dt F - (G * m_e * m_r / r2 ) = v * dm/dt + ma F = Force created by fuel (at time t) G = Gravitational Constant m_e = Mass of Earth m_r = Mass of...
  3. G

    I Maximizing rocket velocity - shoot fuel at once, or slowly?

    I stumbled upon a 3-year old article from Wired that poses this question on rockets: Suppose I have two rockets with a mass M and fuel mass m. Rocket A shoots all the fuel at once (again, like a nuclear propulsion engine) with a fuel speed of u and rocket B shoots two blobs of fuel—first a shot...
  4. D

    Finding the Coefficient of Drag for Partial Parachutes

    Hey Guys, I'm on a rocket team at my university and we are attempting to figure out the force of opening acting on some of our parachutes. Typically this is done using the following equations, in particular, the one in the top right corner. This is where our trouble begins. In the Recovery...
  5. S

    I Steps in designing a rocket

    110kg sounding rocket that runs on apcp im trying to understand the steps to building this rocket what equations do i use to find nozzle parameters and estimated burn time etc. initial surface area for the fuel block is 5020cm^2 burn rate is .6 to 1.2mm a second fuel weight is 100kg gamma for...
  6. hsdrop

    Have we been able to land a rocket upright?

    just an odd question that passed through my mind when i was watching a spacex youtube vid have we (as in humans)ever gotten a rocket to land on the ground with the nose up and the thrusters down (the same position the rocket took of in)???
  7. M

    Rocket meaning - definition

    I was wondering if there is an actual definition given by a recognised organisation over what is meant by the word "rocket". In case there is not, I wanted to reflect upon what do we really mean when we say rockets.
  8. Soyuz-2.1a Rocket Launch

    Soyuz-2.1a Rocket Launch

    Onboard Camera Soyuz-2.1a Rocket Launch
  9. BonesSheppard

    Why buy new model rocket engines?

    Hi I was wondering why are model rocket engines disposable after one use? Is it because it is more economically feasible to buy a new model rocket engine than to repair a used one because the process of using a model rocket engine always ruins it? Also, if it is the case that model rocket...
  10. J

    Model Rocketry Licensing

    If your rocket is of a certain power range you need a certain license. My question is of you need these license's if you are only doing horizontal thrusts tests and never actually launching it vertically into the air?