Electron (Rocket) Launch Vehicle

Electron is a two-stage orbital launch vehicle developed by New Zealand aerospace company Rocket Lab to cover the commercial small satellite launch segment (CubeSats). Its Rutherford engines [more details shown below] are the first electric pump-fed engine to power an orbital rocket.

In December 2016, Rocket Lab announced that Electron had completed flight qualification. The first rocket was launched on 25 May 2017, reaching space but not achieving orbit. During its second flight on 21 January 2018, Electron reached orbit and deployed three CubeSats.

Overview of the Electron

Electron uses two stages with the same diameter (1.2 m, 3 ft 11 in) filled with RP-1/LOX propellant. The main body of the rocket is constructed using a lightweight carbon composite material.

Both stages use the innovative Rutherford rocket engine, the first electric pump-fed engine to power an orbital rocket. There are nine Rutherford engines on the first stage and one vacuum-optimized version on the second stage. Almost all of the engines' parts are 3D-printed to save time and money in the manufacturing process.

The rocket is launched from Rocket Lab Launch Complex 1 on Mahia Peninsula, New Zealand. The launch pad's remote and sparsely-populated location is intended to enable a high frequency of launches. The rocket and launch pad were both privately funded, the first time all parts of a orbital launch operation were entirely run by the private sector (other private spaceflight companies lease launch facilities from government agencies or only launch suborbital rockets).

Intended Usage

Electron is designed to launch a 150 to 225 kg (331 to 496 lb) payload to a 500 km (310 mi) Sun-synchronous orbit, suitable for CubeSats, and other small payloads. The cost is less than US$6 million, a price point that the company hopes will allow it to attract one hundred launches per year. Moon Express has signed a contract to launch a lunar lander on an Electron during 2018 as part of the Google Lunar X Prize.

                                     https://en.wikipedia.org/wiki/Electron_(rocket)

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

Rutherford Rocket Engine

Rutherford is a liquid-propellant rocket engine designed in New Zealand by Rocket Lab and manufactured in the United States. It uses LOX and RP-1 as its propellants and is the first flight-ready engine to use the electric-pump feed cycle. It is used on the company's own rocket, Electron. The rocket uses a similar arrangement to the Falcon 9, a two-stage rocket using a cluster of nine identical engines on the first stage and one, optimized for vacuum operation with a longer nozzle, on the second stage. The sea-level version produces 18 kN (4,000 lbf) of thrust and has a specific impulse of 303 s (2.97 km/s), while the vacuum optimized-version produces 22 kN (4,900 lbf) of thrust and has a specific impulse of 333 s (3.27 km/s).

It was qualified for flight in March 2016 and had its first flight on 25 May 2017.

Description of the Engine

Rutherford, named after New Zealand scientist Lord Rutherford, is a small liquid-propellant rocket engine designed to be simple and cheap to produce. It is used as both a first-stage and as a second-stage engine, which simplifies logistics and improves economies of scale. To reduce its cost, it uses the electric-pump feed cycle, being the first flight-ready engine of such type. It is fabricated largely by 3D printing, using a method called electron-beam melting. Its combustion chamber, injectors, pumps, and main propellant valves are all 3D-printed.

As with all pump-fed engines, the Rutherford uses a rotodynamic pump to increase the pressure from the tanks to that needed by the combustion chamber. The use of a pump avoids the need for heavy tanks capable of holding high pressures and the high amount of gas needed to pressurize them and replaces them with a pump.

The pumps (one for the fuel and one for the oxidizer) in electric-pump feed engines are driven by an electric motor. The Rutherford engine uses dual brushless DC electric motors and a lithium polymer battery. This improves efficiency from the 50% of a typical gas-generator cycle to 95%. However, the battery pack increases the weight of the complete engine.

Each engine has two small motors that generate 50 hp (37 kW) while spinning at 40 000 rpm. The first-stage battery, which has to power the pumps of nine engines simultaneously, can provide over 1 MW of electric power.

The engine is regeneratively cooled, which means that it first passes the fuel through channels that cool the combustion chamber and nozzle before injecting them for combustion.

                        https://en.wikipedia.org/wiki/Rutherford_(rocket_engine)