Motor 1 PLD Space.JPG
First TEPREL-DEMO motor created by PLD Space
Country of origin Spain
DesignerPLD Space
ManufacturerPLD Space
Liquid-fuel engine
Propellantliquid oxygen / kerosene
Mixture ratio2.35
CyclePressure-fed engine (TEPREL-C will use a turbopump)
Thrust30.8 kN
Chamber pressure22 bar
Burn time240 seconds
Used in
Miura 1

TEPREL is a family of rocket engines designed and built by the Spanish aerospace company PLD Space for their Miura 1 and Miura 5 launch vehicles. The TEPREL engine, named after the Spanish reusable engine program that is financing its development, uses kerosene and liquid oxygen as propellants.[1] So far, several versions of this engine, intended to propel Miura 1, have been developed and tested on the company's own liquid propulsion test facilities located in Teruel, Spain.[citation needed]


In the first versions of the engine the propellants are driven to the engine by using a pressure-fed cycle with helium.[2] Later versions of the engine (TEPREL-C) incorporate a turbopump.[3]


The TEPREL-DEMO engine, originally called NetonVac1, was first tested in 2015. It is a calorimetric engine model, intended to demonstrate combustion stability as well as to acquire relevant information such as ignition and shut-down sequences, pressures and temperatures along the engine, thrust and propellant mass flow rates at different thrust profiles. Additionally, the engine served to test all associated hardware and software at PLD Space Propulsion Test Facilities. The engine is capable to produce a thrust of 28 kN at sea level.[4][5]


With the TEPREL-A engine, first tested in 2017, the company included several design upgrades, such as a new combustion chamber design,[6] an improved injector geometry and a regenerative cooling system. The later enables the engine to fire for nearly 2 minutes, which is the envisaged nominal functioning duration for the suborbital launch vehicle Miura 1. At sea level, the engine produces a thrust of 32 kN.[5][4]


TEPREL-B is the first flight version of the TEPREL engine. Several design improvements have been implemented to reduce the overall weight of the engine. It is equipped with a thrust-vector-control system[7] and a convergent-divergent nozzle, all regeneratively cooled.[8] In May 2019 the first unit of this model was destroyed during a test. After a long investigation PLD Space concluded that the problem was due to excess pressure during engine start at ignition. PLD Space addressed the issue through a combination of improvements to the launch site infrastructure and procedural improvements.[9] It is currently fully operational. In February 2020, PLD Space successfully completed a 122-second test that allowed it to achieve flight rating.[10]

On August 28, 2020, PLD Space completed required tests for the thrust vector control system on the Teprel-B rocket engine.[7]


Flight version of the TEPREL engine[11] to be used in the Miura 5 rocket. It will be able to produce 81.6 kN of thrust at sea level.[3]

TEPREL-C vacuum

Version of TEPREL-C adapted to vacuum, and capable of re-ignition in microgravity conditions.[12] Capable of 65 kN of thrust.[3]


  1. ^ "The Spanish Government supports PLD Space launchers development with a $1.56M TEPREL program". pldspace.com. 27 April 2016. Retrieved 27 May 2018.
  2. ^ https://pldspace.com/images/MIURA_1/MIURA1_Payload_Users_Guide.pdf
  3. ^ a b c http://esamultimedia.esa.int/docs/space_transportation/LAUNCHER_WS_Presentation_PLDSpace.pdf
  4. ^ a b "PLD Space ready to test its new engine". pldspace.com. 10 Jul 2017. Retrieved 27 May 2018.
  5. ^ a b Marín, Daniel (16 Feb 2018). "Europa apuesta por PLD Space para alcanzar el espacio". Retrieved 27 May 2018.
  6. ^ PLD Space [@PLD_Space] (5 July 2017). "Hoy tenemos el honor de presentar la nueva cámara de combustión de TEPREL-A,nuevo motor cohete regenerativo de @PLD_Space #GoPLD #GoARION1 t.co/SSi7uJJVRN" (Tweet) (in Spanish). Retrieved 31 December 2020 – via Twitter.
  7. ^ a b "PLD Space completes critical testing of its Teprel-B rocket engine". 31 August 2020.
  8. ^ Raúl Torres🇪🇸 [@RaulTorresPLD] (2 September 2020). "@CarCamMar @PLD_Space Yes, to all. #TEPREL-B has convergent-Divergent nozzle, all regeneratively cooled, providing 32.3kN (SL) at full thrust and designed to work more than 1000s accumulated" (Tweet). Retrieved 31 December 2020 – via Twitter.
  9. ^ "PLD Space books first suborbital flight, nears resolution of engine setback". 5 February 2020.
  10. ^ https://www.defensa.com/aeronautica-y-espacio/exito-ensayo-motor-cohete-para-lanzador-reutilizable-pld-space
  11. ^ "PLD Space más cerca del espacio". 9 January 2017.
  12. ^ Raúl Torres🇪🇸 [@RaulTorresPLD] (3 August 2020). "@Eurekablog @PLD_Space Arriba a la derecha, en otro palé se ve la cuaderna que hay entre el tanque de oxígeno y la interetapa de MIURA5, también sometida a ensayo destructivo. Al fondo de la imagen, se aprecia uno de los laterales del "erector" de MIURA 1, en el foso de ensamblaje" (Tweet) (in Spanish). Retrieved 31 December 2020 – via Twitter.