Testing is being carried out by GKN Aerospace Sweden for an alcohol-based aviation biofuel developed and manufactured by Swedish Biofuels AB
The Swedish Defence Material Administration has contracted GKN Aerospace engineers to continue testing on an alcohol-to-jet based aviation biofuel for use on the Saab AB Gripen fighter jet RM12 engine in a seven-year joint study bilateral Biojet-project collaboration involving the Swedish Defence Material Administration, US Air Force and US Navy which started in 2013 and will be completed by 2020.
The alcohol-based aviation biofuel is developed and manufactured by Swedish Biofuels AB. Testing is being carried out by GKN Aerospace Sweden in special test cells to give in-dept data to compare potential differences to earlier test flight using a 50/50 biofuel mix. Parameters such as flexibility in measurement systems, designing, fuel feed supply to the engine will be measured to demonstrate the capability of the new fuel.
Gripen RM12 Engine
The RM12, a version of the General Electric F404 is a low-bypass afterburning turbofan jet engine developed for the Saab AB Gripen jet fighter by GKN Aerospace Engine Systems of Sweden. The company has reviewed fuel specifications and material compatibility testing to ensure safe engine operation for all fuel-whetted components using the experimental alcohol-to-jet-based biofuel.
The original General Electric F404 engine has been extensively modified by GKN Aerospace Engine Systems to provide greater reliability in regards to single-engine operation, stringent bird strike protection, greater thrust force, and the employment of a full authority digital engine FADEC system which uses digital data buses and a hydromechanical backup as redundancy to communicate with the cockpit replacing the analogue engine control unit.
The aircraft FADEC was jointly developed by Volvo and General Electric. Maintenance demands have been reduced due to the redesign of several subsystems and components. Overall cross-section of the aircraft has been reduced by redesigning the air intakes of the engine to minimize radar reflection from the compressor turbine.
General Electric produces 50% of the engine, with other elements such as the compressor spool, hubs, fan, compressor discs, casing, and afterburner manufactured in Sweden where final assembly of the engine takes place.
Preliminary Tests
Earlier in March 2017, a Gripen C/D jet fighter equipped with an RM12 engine powered by 100% renewable biofuel completed a successful flight demonstration. The aircraft exhibited excellent performance characteristics for this demonstration with no engine changes or modifications both in-flight and on the ground.
The advanced biofuel (CHCJ-5) used on the test flight in 2017 was developed by Applied Research Associates, Inc., a US company on contract with Naval Air Systems Command (NAVAIR) providing material support for aircraft and airborne weapons systems for the United States Navy. The biofuel was fully interchangeable with normal jet fuel and approved for limited flight test.
GKN Aerospace
Vice president for government and space programs, GKN Aerospace, Professor Stephan Oscarsson stated that this is an exciting milestone, The Swedish Defence Materiel Administration (FMV) contract will help build understanding and experimental data takes GKN Aerospace further towards sustainable aviation, a key area of growth for the company. FMV and GKN Aerospace have a strong commitment to renewable fuels, sustainable aviation and reduced environmental impact of aerospace.
GKN Aerospace is involved with the largest European research program, Clean Sky, to develop cutting-edge technology with an innovative approach to reduce CO2 emissions and noise levels produced by aircraft.
References
- Biofuels International <https://biofuels-news.com/news/swedish-air-force-meets-its-mach-with-jet-engine-biofuels-testing/>
- Intelligent Aerospace <https://www.intelligent-aerospace.com/military/article/14178637/gkn-aerospace-continues-jet-engine-biofuel-testing>
- Aerospace Testing International <https://www.aerospacetestinginternational.com/news/defense/gkn-to-test-50-50-biofuel-on-gripen-engine.html>
- GKN Aerospace <https://www.gknaerospace.com/>
- Saab AB <https://saab.com/gripen/>
