Editing Hybrid-propellant rocket (section)

== Organizations working on hybrids ==
===Commercial companies===
In 1998 [[SpaceDev]] acquired all of the intellectual property, designs, and test results generated by over 200&nbsp;hybrid rocket motor firings by the [[American Rocket Company]] over its eight-year life. [[SpaceShipOne]], the first private crewed spacecraft, was powered by SpaceDev's hybrid rocket motor burning [[HTPB]] with [[nitrous oxide]]. However, [[nitrous oxide]] was the prime substance responsible for the explosion that killed three in the development of [[SpaceShipTwo|the successor of SpaceShipOne]] at [[Scaled Composites]] in 2007.<ref>{{cite news |first=Bianca |last=Bosker |date=30 November 2009 |title=Virgin Galactic SpaceShipTwo getting ready for test flights ahead of space tourism |website=HuffPost |url=http://www.huffingtonpost.com/2009/11/30/virgin-galactic-spaceship_n_373978.html}}</ref><ref>{{cite web |first=Lucian |last=Dorneanu |title=Spaceship explosion at the Mojave Desert test area kills&nbsp;2 |date=July 27, 2007 |url=http://news.softpedia.com/news/Spaceship-Test-at-the-Mojave-Desert-Test-Area-Kills-2-61171.shtml}}</ref> The [[Virgin Galactic]] [[SpaceShipTwo]] follow-on commercial suborbital spaceplane uses a scaled-up hybrid motor.

SpaceDev was developing the [[SpaceDev Streaker]], an expendable small launch vehicle, and [[SpaceDev Dream Chaser]], capable of both suborbital and orbital human space flight. Both Streaker and Dream Chaser use hybrid rocket motors that burn [[nitrous oxide]] and the synthetic [[HTPB]] rubber. SpaceDev was acquired by [[Sierra Nevada Corporation]] in 2009, becoming its Space Systems division, which continues to develop Dream Chaser for NASA's [[Commercial Crew Development]] contract. Sierra Nevada also developed [[RocketMotorTwo]], the hybrid engine for [[SpaceShipTwo]]. On October 31, 2014, when [[SpaceShipTwo]] was lost, initial speculation had suggested that its hybrid engine had in fact exploded and killed one test pilot and seriously injured the other. However, investigation data now indicates an early deployment of the SpaceShip-Two feather system was the cause for aerodynamic breakup of the vehicle.<ref>{{cite news |title=Virgin Galactic's SpaceShipTwo crashes: 1&nbsp;dead, 1&nbsp;injured |publisher=NBC News |url=http://www.nbcnews.com/storyline/virgin-voyage/virgin-galactics-spaceshiptwo-crashes-1-dead-1-injured-n238376}}</ref>

U.S. Rockets<ref>{{cite web |title=CRR 457mm |url=http://v-serv.com/usr/crr457mm.htm |access-date=January 2, 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140102194742/http://v-serv.com/usr/crr457mm.htm |archive-date=January 2, 2014 }}</ref> manufactured and deployed hybrids using self-pressurizing [[nitrous oxide]] (N<sub>2</sub>O) and [[hydroxyl-terminated polybutadiene]] (HTPB) as well as mixed [[High-test peroxide]] (HTP) and [[HTPB]]. The [[High-test peroxide]] (H<sub>2</sub>O<sub>2</sub>) 86% and (HTPB) and aluminum hybrids developed by U.S. Rockets produced a sea level delivered specific impulse (I<sub>sp</sub>) of 240, well above the typical 180 of [[nitrous oxide|N<sub>2</sub>O]]-[[HTPB]] hybrids. In addition to that, they were self-starting, restartable, had considerably lower combustion instability making them suitable for fragile or crewed missions such as Bloodhound SSC, SpaceShipTwo or SpaceShipThree. The company had successfully tested<ref name="USR Hybrid">{{cite AV media |medium=video |title=An 18"&nbsp;diameter self-starting and ending HTP-HTPB hybrid near Garlock, CA |url=http://v-serv.com/usr/motors/images/18in/HTP-HybridFiring01.mov |date=17 October 2009 |access-date=31 December 2013 |archive-date=March 3, 2016 |archive-url=https://web.archive.org/web/20160303222729/http://v-serv.com/usr/motors/images/18in/HTP-HybridFiring01.mov |url-status=dead }}</ref> and deployed both pressure fed and pump fed versions of the latter [[High-test peroxide|HTP]]-[[HTPB]] style. Deliverables to date have ranged from {{convert|6|to|18|in|cm|adj=on|order=flip}} diameter, and developed units up to {{convert|54|in|cm|adj=on|order=flip}} diameter. The vendor claimed scalability to over {{convert|5|m|in|adj=on}} diameter with regression rates approaching solids, according to literature distributed at the November&nbsp;2013 [[Defense Advanced Research Projects Agency]] (DARPA) meeting for XS-1. U.S.&nbsp;Rockets is no longer manufacturing large-scale rockets.<ref>{{cite web |publisher=U.S. Rockets |title=Manufacturing announcement |url=https://www.facebook.com/pg/US-Rockets-219639027743/posts/?ref=page_internal}}</ref>{{failed verification|date=September 2020}}

[[Gilmour Space Technologies]] began testing Hybrid rocket engines in 2015 with both [[nitrous oxide|N<sub>2</sub>O]] and HP with [[HDPE]] and [[HDPE]]+wax blends. For 2016 testing includes a {{cvt|5000|lbf|N|order=flip}} HP/[[polyethylene|PE]] engine. The company is planning to use hybrids for both [[sounding rocket|sounding]] and orbital rockets.

Orbital Technologies Corporation (Orbitec) has been involved in some U.S. government-funded research on hybrid rockets including the "Vortex Hybrid" concept.<ref>{{cite web |url=http://orbitec.com/documents/hybrid_rocket_motor.html |publisher=Orbitec |title=Orbitec Vortex Hybrid Test, with photo |access-date=23 April 2016 |archive-date=January 22, 2017 |archive-url=https://web.archive.org/web/20170122153335/http://orbitec.com/documents/hybrid_rocket_motor.html |url-status=dead }}</ref>

Environmental Aeroscience Corporation (eAc)<ref name="EAC home">{{cite web |title=EAC Company home page |publisher=Environmental Aeroscience Corporation |url=http://www.hybrids.com/ |access-date=4 October 2017}}</ref> was incorporated in 1994 to develop hybrid rocket propulsion systems. It was included in the design competition for the [[SpaceShipOne]] motor but lost the contract to SpaceDev. Environmental Aeroscience Corporation still supplied parts to SpaceDev for the oxidizer fill, vent, and dump system.<ref>{{cite web |title=Tier&nbsp;1 |publisher=Environmental Aeroscience Corporation |url=http://www.hybrids.com/tier1.html}}</ref>

[[Rocket Lab]] formerly sold hybrid [[sounding rocket]]s and related technology.

The [[Reaction Research Society]] (RRS), although known primarily for their work with liquid rocket propulsion, has a long history of research and development with hybrid rocket propulsion.

[[Copenhagen Suborbitals]], a Danish rocket group, has designed and test-fired several hybrids using [[nitrous oxide|N<sub>2</sub>O]] at first and currently [[liquid oxygen|LOX]]. Their fuel is epoxy, [[paraffin wax]], or [[polyurethane]].<ref>{{cite web |title=HEAT booster development and tests, with photos and video |publisher=Copenhagen Suborbitals |url=http://copenhagensuborbitals.com/boosters.php |access-date=3 June 2010 |archive-url=https://web.archive.org/web/20100527001602/http://www.copenhagensuborbitals.com/boosters.php |archive-date=May 27, 2010 }}</ref> The group eventually moved away from hybrids because of thrust instabilities, and now uses a motor similar to that of the [[V-2 rocket]].

[[TiSPACE]] is a Taiwanese company which is developing a family of hybrid-propellant rockets.<ref name="Taipei Times 2019" >{{cite news |last1=Chia-nan |first1=Lin |title=Firm sets sights on heavens as space industry develops |series=Feature |newspaper=Taipei Times |url=http://www.taipeitimes.com/News/taiwan/archives/2019/12/15/2003727591 |access-date=17 February 2020}}</ref>

[[bluShift Aerospace]] in [[Brunswick, Maine]], won a [[NASA]] [[Small Business Innovation Research|SBIR]] grant to develop a modular hybrid rocket engine for its proprietary bio-derived fuel in June 2019.<ref>{{Cite web|last=Brogan|first=Beth|date=2019-06-21|title=Brunswick aerospace company lands NASA grant to develop hybrid rocket engine|url=https://bangordailynews.com/2019/06/21/news/brunswick-aerospace-company-lands-nasa-grant-to-develop-hybrid-rocket-engine/|access-date=2020-10-27|website=Bangor Daily News|language=en-US}}</ref> Having completed the grant bluShift has launched its first sounding rocket using the technology.<ref>{{Cite web|last=O'Brien|first=Jane|date=2021-02-01|title=Groundbreaking biofuel rocket could be 'Uber for space'|url=https://www.bbc.com/news/world-us-canada-55845762|access-date=2021-02-03|website=BBC News}}</ref>

Vaya Space based out of Cocoa, Florida, is expected to launch its hybrid fuel rocket Dauntless in 2023.<ref>{{Cite web|date=2021-04-01|title=Space Coast company Rocket Crafters rebrands to Vaya Space and announces bigger rocket|url=https://spaceexplored.com/2021/04/01/space-coast-company-rocket-crafters-rebrands-to-vaya-space-and-announces-bigger-rocket/|access-date=2022-02-07|website=Space Explored|language=en-US}}</ref><ref>{{Cite web|title=Florida rocket company rebrands, plans bigger rocket|url=https://www.upi.com/Science_News/2021/03/31/Rocket-Crafters-rebrands-Vaya-Space-Sid-Gutierrez/5591617132237/|access-date=2022-02-07|website=UPI|language=en}}</ref>

Reaction Dynamics based out Saint-Jean-sur-Richelieu, Quebec, began developing a hybrid rocket engine in 2017 capable of producing 21.6&nbsp;kN of thrust. Their Aurora rocket will use nine engines on the first stage and one engine on the second stage and will be capable of delivering a payload of 50–150&nbsp;kg to LEO.<ref>{{Cite web |title=Aurora {{!}} Reaction Dynamics |url=https://www.reactiondynamics.space/aurora |access-date=2022-09-10 |website=www.reactiondynamics.space}}</ref> In May 2022, Reaction Dynamics announced they were partnering with [[Maritime Launch Services]] to launch the Aurora rocket from their launch site currently under construction in [[Canso, Nova Scotia]], beginning with suborbital test flights in Summer, 2023 with a target of 2024 for the first orbital launch.<ref>{{Cite news |date=2022-05-04 |title=All-Canadian Space Launch Solution Plans Inaugural Flight for 2023 |language=en |work=Financial Post |url=https://financialpost.com/pmn/press-releases-pmn/business-wire-news-releases-pmn/all-canadian-space-launch-solution-plans-inaugural-flight-for-2023 |access-date=2022-09-10}}</ref>

In 2017 DeltaV Uzay Teknolojileri A.Ş. was founded by Savunma Sanayi Teknolojileri A.Ş (SSTEK), a state company of Turkey, for hybrid-propellant-rocket research. The company CEO Arif Karabeyoglu is former Consulting Professor of  Stanford University  in the area of rocket propulsion and combustion. According to company web site DeltaV achieved many firsts in hybrid-propellant-rocket technology including first paraffin/LOX dual fuel rocket launch, highest specific impulses for a hybrid-propellant-rocket, first sounding rocket to reach 100 km altittude, first orbital hybrid-propellant-rocket design, first orbital firing of hybrid-propellant-rocket.{{cn|date=July 2024}}

===Universities===
Space Propulsion Group was founded in 1999 by Arif Karabeyoglu, Brian Cantwell, and others from [[Stanford University]] to develop high regression-rate liquefying hybrid rocket fuels. They have successfully fired motors as large as {{cvt|12.5|in|cm}}. diameter which produce {{cvt|13,000|lbf}} using the technology and are currently developing a {{cvt|24|in|cm}} diameter, {{cvt|25,000|lbf}} motor to be initially fired in 2010. [[Stanford University]] is the institution where liquid-layer combustion theory for hybrid rockets was developed. The SPaSE group at Stanford is currently working with [[NASA Ames Research Center]] developing the Peregrine [[sounding rocket]] which will be capable of 100&nbsp;km altitude.<ref>{{cite web |title=Peregrine rocket poster |year=2008 |publisher=Stanford University |url=http://www.stanford.edu/dept/aeroastro/aeroastro/50th/posters/peregrine.pdf |url-status=dead |archive-url=https://web.archive.org/web/20090227121236/http://www.stanford.edu/dept/aeroastro/aeroastro/50th/posters/peregrine.pdf |archive-date=February 27, 2009}}</ref> Engineering challenges include various types of combustion instabilities.<ref>{{cite web |title=Peregrine rocket poster |year=2012 |publisher=Stanford University |url=http://aa.stanford.edu/students/media/posters2012/waxman.pdf |url-status=dead |archive-url=https://web.archive.org/web/20140413192658/http://aa.stanford.edu/students/media/posters2012/waxman.pdf |archive-date=April 13, 2014 }}</ref> Although the proposed motor was test fired in 2013, the Peregrine program eventually switched to a standard solid rocket for its 2016 debut.
[[File:Helical Flow Hybrid University of Tennessee.jpg|thumb|Helical oxidizer injection into a plexiglass hybrid. Image was taken during shutdown, enabling flow pattern to be seen. University of Tennessee at Knoxville.]]
The University of Tennessee Knoxville has carried out hybrid rocket research since 1999, working in collaboration with NASA Marshall Space Flight Center and private industry. This work has included the integration of a water-cooled calorimeter nozzle, one of the first 3D-printed, hot section components successfully used in a rocket motor.<ref>{{cite journal |first1=Nick |last1=Quigley |first2=J.E. |last2=Lyne <!-- The University of Tennessee at Knoxville --> |date=November–December 2014 |title=Development of a three-dimensional printed, liquid-cooled nozzle for a hybrid rocket |journal=Journal of Propulsion and Power |doi=10.2514/1.B35455 |s2cid=120692404 |url=https://www.researchgate.net/publication/269567431 |via=ResearchGate}}</ref> Other work at the university has focused on the use of helical oxidizer injection, bio-derived fuels<ref>{{cite thesis |last=Putnam |first=Scott Grayson |year=2007 |title=Investigation of non-conventional bio-derived fuels for hybrid rocket motors |degree=Ph.D. |publisher=University of Tennessee |department=Aerospace Engineering |url=https://trace.tennessee.edu/utk_graddiss/269}}</ref> and powdered fuels encased in a 3D-printed, [[acrylonitrile butadiene styrene|ABS]] matrix, including the successful launch of a coal-fired hybrid at the 2019 Spaceport America Cup.<ref name=":0" /><ref name=":1" />

At the [[Delft University of Technology]], the student team [[Delft Aerospace Rocket Engineering]] (DARE) is very active in the design and building of hybrid rockets. In October&nbsp;2015, DARE broke the European student altitude record with the Stratos&nbsp;II+ [[sounding rocket]]. Stratos&nbsp;II+ was propelled by the DHX-200 hybrid rocket engine, using a [[nitrous oxide]] oxidizer and fuel blend of paraffin, [[sorbitol]] and aluminium powder. On July 26, 2018, DARE attempted to launch the Stratos&nbsp;III hybrid rocket. This rocket used the same fuel/oxidizer combination as its predecessor, but with an increased impulse of around 360&nbsp;kNs.<ref>P.M. van den Berg, F. Barreiro, C.L. Klop, D.A. van Strydonck, S.T. Koehler, Development of a 25kN Hybrid Rocket Engine for the Stratos III sounding rocket, 69th International Astronautical Congress (IAC), Bremen, Germany, 1–5 October 2018</ref> At the time of development, this was the most powerful hybrid rocket engine ever developed by a student team in terms of total impulse. The Stratos III vehicle was lost 20&nbsp;seconds into the flight.<ref>{{cite report |title=Stratos&nbsp;III launch summary |date=July 2018 |publisher=Delft University of Technology |place=Delft, NL |url=https://dare.tudelft.nl/2018/07/stratos-iii-launch-summary/ |access-date=May 29, 2020 |archive-date=September 23, 2021 |archive-url=https://web.archive.org/web/20210923215445/https://dare.tudelft.nl/2018/07/stratos-iii-launch-summary/ |url-status=dead }}</ref>

[[Florida Institute of Technology]] has successfully tested and evaluated hybrid technologies with their Panther Project. The [[WARR (research group)|WARR]]<ref>{{cite web |title=Raketentechnik |website=warr.de |url=http://www.warr.de/raketentechnik |access-date=June 27, 2011 |url-status=dead |archive-url=https://web.archive.org/web/20111206195845/http://www.warr.de/raketentechnik |archive-date=6 December 2011}}</ref> student-team at the [[Technical University of Munich]] has been developing hybrid engines and rockets since the early 1970s. Using [[acids]], [[oxygen]], or [[nitrous oxide]] in combination with [[polyethylene]], or [[HTPB]]. The development includes test stand engines as well as airborne versions, like the first German hybrid rocket [[Barbarella (rocket)|Barbarella]]. They are currently working on a hybrid rocket with [[Liquid oxygen]] as its oxidizer, to break the European height record of amateur rockets. They are also working with Rocket Crafters and testing their hybrid rockets.

[[Boston University]]'s student-run "Rocket Propulsion Group",<ref>{{cite web |title=Rocket Propulsion Group |publisher=Boston University |place=Boston, MA |url=http://www.burocket.org/}}</ref> which in the past has launched only solid motor rockets, is attempting to design and build a single-stage hybrid [[sounding rocket]] to launch into sub-orbital space by July&nbsp;2015.<ref>{{cite web |department=Rocket Propulsion Group |title=Starscraper |publisher=Boston University |url=http://www.burocket.org/rockets/starscraper/ |archive-url=https://web.archive.org/web/20150103074130/http://www.burocket.org/rockets/starscraper/ |archive-date=3 January 2015}}</ref>

[[Brigham Young University]] (BYU), the [[University of Utah]], and [[Utah State University]] launched a student-designed rocket called Unity&nbsp;IV in 1995 which burned the solid fuel [[hydroxyl-terminated polybutadiene]] (HTPB) with an oxidizer of gaseous [[oxygen]], and in 2003 launched a larger version which burned [[HTPB]] with [[nitrous oxide]].

The [[University of Brasília|University of Brasilia's (UnB)]] Hybrid Rocket Team initiated their endeavors in 1999 within the Faculty of Technology, marking the pioneering institution in the Southern Hemisphere to engage with hybrid rockets. Over time, the team has achieved notable milestones, encompassing the creation of various sounding rockets and hybrid rocket engines. Presently, the team is known as the Chemical Propulsion Laboratory (CPL) and is situated at Campus UnB Gama. CPL has made significant strides in the advancement of critical hybrid engine technologies. This includes the development of a modular 1&nbsp;kN hybrid rocket engine for the SARA platform, an innovative methane-oxygen gas-torch ignition system, an efficient oxidizer feed system, precision flow control valves, and thrust vector control mechanisms tailored for hybrid engines. Additionally, they've achieved a breakthrough with a 3D-printed, actively cooled hybrid rocket engine. Furthermore, the Laboratory is actively engaged in diverse areas of research and development, with current projects spanning the formulation of hybrid engine fuels using paraffin wax and N2O, numerical simulations, optimization techniques, and rocket design. CPL collaborates extensively with governmental agencies, private investors, and other educational institutions, including FAPDF, FAPESP, CNPq, and AEB. A notable collaborative effort includes the Capital Rocket Team (CRT), a group of students from UnB, who are currently partnering with CPL to develop hybrid sounding rockets. In a remarkable achievement, CRT clinched the top spot in the 2022 Latin American Space Challenge (LASC).

[[University of California, Los Angeles]]'s student-run "Rocket Project at UCLA" launches hybrid propulsion rockets using [[nitrous oxide]] as an oxidizer and [[HTPB]] as the fuel. They are currently in the development process of their fifth student-built hybrid rocket engine.<ref>{{Cite web |title=Ares {{!}} RP@UCLA |url=http://rocketproject.seas.ucla.edu/Ares.html |access-date=2022-05-02 |website=rocketproject.seas.ucla.edu |archive-date=September 11, 2022 |archive-url=https://web.archive.org/web/20220911040926/http://rocketproject.seas.ucla.edu/Ares.html |url-status=dead }}</ref>

[[University of Toronto]]'s student-run "University of Toronto Aerospace Team", designs and builds hybrid engine powered rockets. They are currently constructing a new engine testing facility at the [[University of Toronto Institute for Aerospace Studies]], and are working towards breaking the Canadian amateur rocketry altitude record with their new rocket, Defiance MKIII, currently under rigorous testing. Defiance MK&nbsp;III's engine, QUASAR, is a [[Nitrous oxide|Nitrous]]-[[Paraffin wax|Paraffin]] hybrid engine, capable of producing 7&nbsp;kN of thrust for a period of 9&nbsp;seconds.{{citation needed|date=September 2020}}

In 2016, [[Pakistan]]'s [[DHA Suffa University]] successfully developed<ref>{{cite AV media |title=First hybrid rocket engine of Pakistan |medium=video |url=https://www.youtube.com/watch?v=d8kBpVOVBkE  |archive-url=https://ghostarchive.org/varchive/youtube/20211211/d8kBpVOVBkE| archive-date=2021-12-11 |url-status=live|via=YouTube}}{{cbignore}}</ref> Raheel-1, hybrid rocket engines in 1&nbsp;kN class, using [[paraffin wax]] and [[liquid oxygen]], thereby becoming the first university run rocket research program in the country.<ref>{{cite news |title=Pakistan's first-ever hybrid rocket readying for launch |newspaper=The Express Tribune |url=http://tribune.com.pk/story/1170610/lift-off-pakistans-first-ever-hybrid-rocket-readying-launch/}}</ref> In [[India]], [[Birla Institute of Technology, Mesra]] Space engineering and rocketry department has been working on Hybrid Projects with various fuels and oxidizers.

[[Pars Rocketry]] Group from [[Istanbul Technical University]] has designed and built the first hybrid rocket engine of [[Turkey]], the rocket engine extensively tested in May&nbsp;2015.<ref>{{cite web |title=ITU24 |series=Pars Rocketry Team |publisher=Istanbul Technical University |url=http://itu24.com/haber/pars-roket-takimi-1361}}</ref>

A United Kingdom-based team (laffin-gas) is using four [[nitrous oxide|N<sub>2</sub>O]] hybrid rockets in a drag-racing style car. Each rocket has an outer diameter of 150&nbsp;mm and is 1.4&nbsp;m long. They use a fuel grain of high-density wound paper soaked in cooking oil. The [[nitrous oxide|N<sub>2</sub>O]] supply is provided by Nitrogen-pressurised piston accumulators which provide a higher rate of delivery than [[nitrous oxide|N<sub>2</sub>O]] gas alone and also provide damping of any reverse shock.{{citation needed|date=September 2020}}

In Italy one of the leading centers for research in hybrid propellants rockets is CISAS (Center of Studies and Activities for Space) "G. Colombo", [[University of Padua]]. The activities cover all stages of the development: from theoretical analysis of the combustion process to numerical simulation using CFD codes, and then by conducting ground tests of small scale and large-scale rockets (up to 20&nbsp;kN, [[nitrous oxide|N<sub>2</sub>O]]-[[Paraffin wax]] based motors). One of these engines flew successfully in 2009. Since 2014, the research group is focused on the use of [[high test peroxide]] as oxidizer, in partnership with "Technology for Propulsion and Innovation", a university of Padua spin-off company.<ref>{{cite web |title=Hybrid propellant &#124; T4i |publisher=Space Technology for Innovation |url=http://www.t4innovation.com/chemical-thrusters/hybrid-propellant/}}</ref>

In [[Taiwan]], hybrid rocket system developments began in 2009 through R&D projects of [[NSPO]] with two university teams. Both teams employed [[nitrous oxide]] / [[HTPB]] propellant system with different improvement schemes. Several hybrid rockets have been successfully launched by NCKU and NCTU teams so far, reaching altitudes of 10–20&nbsp;km. Their plans include attempting 100–200&nbsp;km altitude launch to test nanosatellites, and developing orbital launch capabilities for nanosatellites in the long run. A sub-scale [[nitrous oxide|N<sub>2</sub>O]]/[[polyethylene|PE]] dual-vortical-flow (DVF) hybrid engine hot-fire test in 2014 has delivered an averaged Isp of 280 sec, which indicates that the system has reached around 97% combustion efficiency.{{citation needed|date=September 2020}}

In (Germany) the [[University of Stuttgart]]'s Student team HyEnd is the current world record holder for the highest-flying student-built hybrid rocket with their HEROS rockets.<ref>{{cite web |title=HEROS Launches |website=hybrid-engine-development.de |url=http://www.hybrid-engine-development.de/index.php/heros-launches |access-date=April 25, 2018 |archive-date=April 26, 2018 |archive-url=https://web.archive.org/web/20180426075837/http://www.hybrid-engine-development.de/index.php/heros-launches |url-status=dead }}</ref>

In [[Bangladesh]], Amateur Experimental Rocketry Dhaka supported by the American International University Bangladesh has also tested the country's first hybrid rocket engine, and are now working towards larger paraffin/nitrous oxide based prototypes.<ref>{{cite web |title= First hybrid rocket engine in Bangladesh tested successfully |date=September 13, 2023 |url=https://www.thedailystar.net/campus/news/first-hybrid-rocket-engine-bangladesh-tested-successfully-3418016}}</ref>

The ''Aerospace Team'' of the [[Technische Universität Graz|TU Graz]], Austria, is also developing a hybrid-propellant rocket.<ref>{{cite web|title=ASTG Propulsion|url=https://www.astg.at/Propulsion.aspx|date=27 February 2021|access-date=February 27, 2021|archive-date=March 5, 2021|archive-url=https://web.archive.org/web/20210305030608/https://astg.at/Propulsion.aspx|url-status=dead}}</ref>

The Polish Student team PWr in Space at [[Wrocław University of Science and Technology]] has developed three hybrid rockets: R2 "Setka", R3 "Dziewięćdziesiątka dziewiątka" and the most powerful of all - R4 "Lynx" with a successful test at their test stand <ref>{{cite web |title=Rockets - PWr in Space |url=https://pwrinspace.pwr.edu.pl/html/Rockets.html |website=pwrinspace |publisher=PWr in Space |access-date=26 May 2022 }}{{Dead link|date=March 2025 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

Many other universities, such as [[Embry-Riddle Aeronautical University]], the [[University of Washington]], [[Purdue University]], the [[University of Michigan]] at Ann Arbor, the [[University of Arkansas at Little Rock]], [[Hendrix College]], the [[University of Illinois at Urbana–Champaign|University of Illinois]], [[Portland State University]], [[University of KwaZulu-Natal]], [[Texas A&M University]], [[Aarhus University]], [[Rice University]], and [[AGH University of Science and Technology]] have hybrid motor test stands that allow for student research with hybrid rockets.{{citation needed|date=September 2020}}

===High power rocketry===
There are a number of hybrid rocket motor systems available for amateur/hobbyist use in high-powered model rocketry. These include the popular HyperTek systems<ref>{{cite web |title=HyperTEK – The easiest access of them all |website=hypertekhybrids.com |url=http://www.hypertekhybrids.com}}</ref> and a number of 'Urbanski-Colburn Valved' (U/C) systems such as RATTWorks,<ref>{{cite web |title=RATTworks: Precision hybrid & tribrid rocket motors |website=rattworks.net |url=http://www.rattworks.net}}</ref> Contrail Rockets,<ref>{{cite web |title=Contrail Rockets Hybrid Rocket Motors |website=contrailrockets.com |url=http://www.contrailrockets.com/}}</ref> and Propulsion Polymers.<ref>{{cite web |title=初売りで流行のアイテムを入手しよう｜人気のおしゃれグッズ |website=propulsionpolymers.com |url=http://www.propulsionpolymers.com}}</ref>
All of these systems use [[nitrous oxide]] as the oxidizer and a plastic fuel (such as [[Polyvinyl chloride]] (PVC), [[Polypropylene]]), or a polymer-based fuel such as [[HTPB]]. This reduces the cost per flight compared to solid rocket motors, although there is generally more ground support equipment required with hybrids.