We will be discussing Launch Escape Systems (LES). Also called Launch Abort System (LAS), it is a crew safety system connected to the space capsule
Merlin engines are arranged in an Octaweb Structure. ‘Octa’ means eight and ‘web’ structure as it depicts radiating lines from the center. The Octaweb is a metal structure that supports eight engines surrounding a center engine at the base of the launch vehicle. Falcon 9 v1.0 and v1.1 engine. Credits: Craigboy/Wikipedia What is its purpose? The short answer is stability. The Octaweb also reduces the length and weight of the Falcon 9 thrust structure, simplifying the rocket’s design and assembly. Streamlining…
Falcon 9 is powered by a Merlin engine. It has the highest thrust-to-weight ratio of any boost engine ever made, while still maintaining the structural and thermal safety margins needed to carry astronauts. Merlin engines use RP-1 and liquid oxygen as rocket propellants in a gas-generator power cycle. The Merlin engine was originally designed for sea recovery and reuse. Propellants are fed via a single shaft, dual impeller turbopump. The turbopump also provides high-pressure fluid for the hydraulic actuators, which then…
The Vis-viva equation is a fundamental equation used in orbital mechanics which relates the velocity of an object in an orbit around a planet, to its distance from the center of the planet and the semi-major axis of its orbit. The beauty of this equation is that a lot of deductions can be made for different relations between the semi-major axis and the positional distance of the object. Let's see the equation first. Here — v is the relative speed of…
The origin of the principal axes of the rocket comes from the corresponding axes and motion in an aircraft. All three Axes Principal Axes. Photo Credits: NASA Pitch motion The Pitch axis passes through the center of gravity and is parallel to the wings. Pitching motion in an aircraft: Credits: NASA Roll Motion Roll motion in an aircraft. Credits: NASA Yaw motion Yaw motion in an aircraft. Credits: NASA How to find the principal axes in an rocket? In a rocket,…
A Hohmann Transfer is an orbital maneuver that is used to transfer a satellite or spacecraft from one circular orbit to another. It was invented by a German scientist, Walter Hohmann in 1925 and is often (not always) the most fuel-efficient way to get from one circular orbit to another circular orbit. Although it can take a longer time as compared to other orbital maneuvers. To understand this transfer phenomenon, you need to understand a couple of things first. First, each…
The gas generator cycle is one of the most commonly used power cycles in a bipropellant liquid rocket engine. Let us understand the working of a typical Gas generator cycle-based engine using the below diagram. Gas-generator rocket cycle. Photo credits: Duk/Wikipedia Let's start from the topmost part. Liquid fuel and Liquid Oxygen are stored in two separate tanks. These propellants are taken up by two pumps — The fuel pump and the Oxidizer pump, which increases the pressure and temperature of…
The basic principle and working of a liquid fuel rocket are pretty simple. The fuel and oxidizer (together called propellants) are stored in two separate pressurized tanks. These are then pumped into a combustion chamber by use of "pumps". Finally, the exhaust formed because of combustion is made to pass through a de Laval nozzle or a converging-diverging nozzle that accelerates the exhaust gases to very high velocity, resulting in the required thrust. Heinkel He 176 was a German rocket-powered aircraft.…
Max Q stands for “Maximum dynamic pressure.” It’s the moment in the launch when the rocket or shuttle is undergoing “maximum mechanical stress.” Which is just a way of saying the rocket is feeling a lot of physical pressure from going its way through all the air in the atmosphere at a really high speed. In fact, it’s going through the most physical stress it will feel during the entire launch. Consider the situation similar to when you put your hand…
Consider a rocket in space and an observer standing on earth. Rocket Equation Derivation At time t=0, the rocket's total mass is M + Δm. Where M is the mass of the empty rocket and Δm is the mass of the fuel. The entire system is moving at a velocity of V, with respect to an observer on earth. Total Initial momentum of the rocket = Mass x Velocity Pi = (M + Δm) x V At time t= T, the…