CE-7.5

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title: "CE-7.5" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["rocket-engines-of-india", "rocket-engines-using-hydrogen-propellant", "rocket-engines-using-the-staged-combustion-cycle"] description: "Cryogenic rocket engine developed by the Indian Space Research Organisation" topic_path: "geography/india" source: "https://en.wikipedia.org/wiki/CE-7.5" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Cryogenic rocket engine developed by the Indian Space Research Organisation ::

::data[format=table title="Infobox rocket engine"]

Field	Value
image	File:Indigenous Cryogenic Upper Stage of GSLV-F09 at Stage Preparation Facility.jpg
caption	The CUS15 upper stage of GSLV-F09 powered by the CE-7.5 engine at Stage Preparation Facility
name	CE-7.5
country_of_origin	India
designer	ISRO
LPSC
manufacturer	ISRO
HAL
first_date	15 April 2010 (failure)
5 January 2014 (success)
purpose	Upper-stage booster
status	In use
cycle	Fuel-rich staged combustion
type	liquid
fuel	LH2
oxidiser	LOX
combustion_chamber	1
thrust(Vac)	73.5 kN
specific_impulse_vacuum	454 isp
chamber_pressure	5.8 MPa / 7.5 MPa
diameter	1.56 m
length	2.14 m
dry_weight	435 kg
used_in	Upper stage of GSLV
::

| image = File:Indigenous Cryogenic Upper Stage of GSLV-F09 at Stage Preparation Facility.jpg | image_size = | caption = The CUS15 upper stage of GSLV-F09 powered by the CE-7.5 engine at Stage Preparation Facility | name = CE-7.5 | country_of_origin = India | designer = ISRO LPSC | manufacturer = ISRO HAL | first_date = 15 April 2010 (failure) 5 January 2014 (success) | purpose = Upper-stage booster | predecessor = | status = In use | cycle = Fuel-rich staged combustion | type = liquid | fuel = LH2 | oxidiser = LOX | capacity = | combustion_chamber = 1 | nozzle_ratio = | thrust(SL) = | thrust(Vac) = 73.5 kN | specific_impulse_vacuum = 454 isp | specific_impulse_sea_level = | chamber_pressure = 5.8 MPa / 7.5 MPa | thrust_to_weight = | diameter = 1.56 m | length = 2.14 m | dry_weight = 435 kg | used_in = Upper stage of GSLV The CE-7.5 is a cryogenic rocket engine developed by ISRO to power the upper stage of its GSLV Mk-2 launch vehicle. The engine was developed as a part of the Cryogenic Upper Stage Project (CUSP). It replaced the KVD-1 (RD-56) Russian cryogenic engine that powered the upper stage of GSLV Mk-1.

Overview

CE-7.5 is a regeneratively-cooled, variable-thrust, fuel-rich staged combustion cycle rocket engine.

Specifications

The specifications and key characteristics of the engine are:

• Operating Cycle – Staged combustion
• Propellant Combination – LOX / LH2
• Maximum thrust (Vacuum) – 73.55 kN
• Operating Thrust Range (as demonstrated during GSLV Mk2 D5 flight) – 73.55 kN to 82 kN
• Engine Specific Impulse - 454 ±
• Engine Burn Duration (Nom) – 720 seconds
• Propellant Mass – 12,800 kg
• Two independent regulators: thrust control and mixture ratio control
• Steering during thrust: provided by two gimballed steering engines

Development

ISRO formally started the Cryogenic Upper Stage Project in 1994. The engine successfully completed the Flight Acceptance Hot Test in 2008, and was integrated with propellant tanks, third-stage structures and associated feed lines for the first launch. The first flight attempt took place in April 2010 during the GSLV Mk.II D3/GSAT-3 mission. The engine ignited, but the ignition did not sustain as the Fuel Booster Turbo Pump (FBTP) shut down after reaching a speed of about 34,500 rpm 480 milliseconds after ignition, due to the FBTP being starved of Liquid Hydrogen (LH2).

To aid in the development of NGLV, technologies for multiple restart and development of a spark torch igniter was conducted on the Vernier engine of the GSLV CUS in March 2025.

Applications

CE-7.5 is being used in the third stage of ISRO's GSLV Mk.II rocket.

References

References

1. . ["Cryogenic engine test a big success, say ISRO officials"](http://www.newindianexpress.com/states/kerala/article1521560.ece).
2. "GSLV-D3". ISRO.
3. Ramachandran, R.. (22 January 2014). "Russian route".
4. "GSLV-D3 brochure". ISRO.
5. (2014-02-07). "GSLV MkIII, the next milestone". Frontline.
6. "Indigenous Cryogenic Upper Stage".
7. "GSLV-D5". ISRO.
8. "GSLV-D5 launch video – CE-7.5 thrust was uprated by 9.5% to 82 kN and then brought back to nominal thrust of 73.55 kN". Doordarshan National TV.
9. "How ISRO developed the indigenous cryogenic engine". The Economic Times.
10. "Flight Acceptance Hot Test Of Indigenous Cryogenic Engine Successful". ISRO.
11. "Indigenous Cryogenic Upper Stage Successfully Flight Tested On-board GSLV-D5". ISRO.
12. "Multiple restarts of Launch Vehicle Stages - ISRO successfully carried out ignition trial using Spark Torch Igniter".
13. "GSLV - Isro".

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::