The RZ2 was a British design for a LOX / kerosene liquid fuel rocket engine to power the Blue Streak missile

Blue Streak missile

The Blue Streak missile was a British medium range ballistic missile . The Operational Requirement for the missile was issued in 1955 and the design was complete by 1957...

.

The design was a development of the Rolls-Royce RZ1 rocket engine, which had in turn been a development by Rolls-Royce

Rolls-Royce Limited

Rolls-Royce Limited was a renowned British car and, from 1914 on, aero-engine manufacturing company founded by Charles Stewart Rolls and Henry Royce on 15 March 1906 as the result of a partnership formed in 1904....

 of the Rocketdyne S3D.

Two variants of this engine were developed: the first provided a static thrust of 137,000 lbf (62,100 kg) and the second (intended for the three stage satellite launch vehicle) 150,000 lbf (68,000 kg). The engines were unique at that time in that they could be vectored

Thrust vectoring

Thrust vectoring, also thrust vector control or TVC, is the ability of an aircraft, rocket or other vehicle to manipulate the direction of the thrust from its engine or motor in order to control the attitude or angular velocity of the vehicle....

 by seven degrees in flight for guidance.

Some disconnected facts for arrangement:

The Efflux chamber of the engine was made of nickel tubes brazed together through which flowed kerosine down one tube and back up the adjacent tube via a manifold at the mouth of the chamber. After static firings these chambers were checked by climbing inside the engine from beneath (the mouth being 6 feet in diameter this was no problem, but the throat was rather smaller and more constricting. After firing the inside of the chamber was coated with fine carbon, so chamber inspection was not only filthy but had to be done in the most careful fashion as small holes in the tubes were not infrequent.)
At the head of the chamber was the injector plate with concentric circles of Lox and kerosine injectors arranged in such a way that the liquids jets hit one another, like on like. The outer ring, of kerosine injectors helped cool the tubes which formed the chamber walls. From memory the lox pressure was 720 psi and the kerosine 450.
The start sequence was as follows.
-10 secs The start tanks were pressurized.
-7.5 secs The blade valves opened to allow fuel and oxidant to flow to the gas generator and on to the pump turbines. These turbines accelerated from 0 ro 30,000rpm in 32mSecs and drove pumps through a 6 to 1 reduction gearbox which forced the propellants into the engines.
-4 secs main engine burn commenced.
-2.5 secs Full thrust was achieved.
0 secs Vehicle release.

Lift off was required to be at 1.3 g to enable the ground equipment to be cleared. Bearing in mind the nature of the autopilot the vehicle tended to rotate about its long axis and move laterally at release as a result of standing small corrections implemented through the vectoring of the engines. With the RZ2 Mk 3 developing 150,000 lbs of thrust this meant that the all up weight of the vehicle at lift off was about 230,000 lbs or a little over 100 tons.
Because of the limited gain change abilities of the autopilot, as the weight of the vehicle fell the corrections applied by vectoring the engines were more vigorous at lighter weights and even on ground tests the engines be seen not to be entirely rigid as the mouth of the chamber moved slightly after the corrections were applied by the hydraulic rams. These rams were fed by hydraulic fluid at about 3,000 psi.

The dynamic pressure at the chamber mouth was about 6 psi.

Display examples

• Alongside the Blue Streak at the National Space Centre
  National Space Centre
  The National Space Centre is one of the United Kingdom's leading visitor attractions that is devoted to space science and astronomy. It is located in the city of Leicester, England, next to the River Soar on the A6.-History:...
  
   in Leicester
  Leicester
  Leicester is a city and unitary authority in the East Midlands of England, and the county town of Leicestershire. The city lies on the River Soar and at the edge of the National Forest...
  
  
• Armagh Planetarium
  Armagh Planetarium
  Armagh Planetarium is a planetarium located in Armagh, Northern Ireland close to the city centre and neighbouring Armagh Observatory in approximately fourteen acres of landscaped grounds known as the Armagh Astropark.- History :...
  
  
• The Euro Space Center
  Euro Space Center
  Euro Space Center is an educational tourist attraction located in Transinne, Belgium, near Redu, devoted to space and astronautics. The centre includes simulators of space flight and micro-gravity...
  
   in Redu
  Redu
  Redu is a village in the municipality of Libin, in Luxembourg province, Belgium. The village is twinned with Hay-on-Wye in the United Kingdom and it is one of the very first book towns....
  
  , Belgium.