Space Techno: FALCON 9 OVERVIEW

this post is created by mooiz

Falcon 9 User's Guide (2.9 mb)

The Falcon launch vehicle family is designed to provide breakthrough advances in reliability, cost, flight environment and time to launch. The primary design driver is and will remain reliability, as described in more detail below. We recognize that nothing is more important than getting our customer's spacecraft safely to its intended destination.

Like Falcon 1, Falcon 9 is a two stage, liquid oxygen and rocket grade kerosene (RP-1) powered launch vehicle. It uses the same engines, structural architecture (with a wider diameter), avionics and launch system.

Length:                                    54.9 m (180 ft)

Width:                                    3.6 m (12 ft)

Mass (LEO, 5.2m fairing):      333,400 kg (735,000 lb)

Mass (GTO, 5.2m fairing):     332,800 kg (733,800 lb)

Thrust (vacuum):                    4.94 MN (1,110,000 lbf)

Falcon 9 has nine Merlin engines clustered together. This vehicle will be capable of sustaining an engine failure at any point in flight and still successfully completing its mission. This actually results in an even higher level of reliability than a single engine stage. The SpaceX nine engine architecture is an improved version of the architecture employed by the Saturn V and Saturn I rockets of the Apollo Program, which had flawless flight records despite losing engines on a number of missions.

Another notable point is the SpaceX hold-before-release system — a capability required by commercial airplanes, but not implemented on many launch vehicles. After first stage engine start, the Falcon is held down and not released for flight until all propulsion and vehicle systems are confirmed to be operating normally. An automatic safe shut-down and unloading of propellant occurs if any off nominal conditions are detected.

The main engine, called Merlin, was developed internally at SpaceX, but draws upon a long heritage of space proven engines. The pintle style injector at the heart of Merlin was first used in the Apollo Moon program for the lunar module landing engine, one of the most critical phases of the mission.

Propellant is fed via a single shaft, dual impeller turbo-pump operating on a gas generator cycle. The turbo-pump also provides the high pressure kerosene for the hydraulic actuators, which then recycles into the low pressure inlet. This eliminates the need for a separate hydraulic power system and means that thrust vector control failure by running out of hydraulic fluid is not possible. A third use of the turbo-pump is to provide roll control by actuating the turbine exhaust nozzle (on the second stage engine).

Combining the above three functions into one device that we know is functioning before the vehicle is allowed to lift off means a significant improvement in system level reliability.

Sea Level Thrust :        556 kN (125,000 lbf)

Vacuum Thrust:           617 kN (138,800 lbf)

Sea Level Isp:             275s

Vacuum Isp:               304s

With a vacuum specific impulse of 304s, Merlin is the highest performance gas generator cycle kerosene engine ever built, exceeding the Boeing Delta II main engine, the Lockheed Atlas II main engine and the Saturn V F-1.