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Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 4/97 ITP DEVELOPS THRUST-VECTORING NOZZLE FOR EJ200 by Karl Schwarz Flight tests in the USA have shown the advantages of thrust vector control in fighter aircraft. The Russian manufacturer Sukhoi finds swivel nozzles attractive also and has fitted its Su-37 with this technology. Western Europe is not that advanced yet. However, Dasa has achieved some valuable experiences with its vector-controlled X-31. This technology gap is now to be filled. Following some years of feasibility studies by SENER, Spains ITP (Industria de Turbo Propulsores) began with a technology program at the end of 1994. This program is designed to lead to test bench runs of a functional thrust vector nozzle by the beginning of 1998. A Eurojet EJ2000, which was developed for the Eurofighter 2000, will be used for the tests. According to ITP, the test nozzle will be able to deflect the thrust in angles up to 20 degrees and in all directions. The nozzle area will be controllable also. Unlike other designs, all functions will work through one motion system. This is possible by using a relatively simple mechanical arrangement, comprising of three rings. The hydraulic actuators are only connected to the outer ring which moves the divergent nozzle segments via rods. Differential movements of the four servos can tilt the ring in any direction, such deflecting the thrust. Also, the ring is split into an upper and into a lower segment which are hinged in the middle. This allows for the folding or extending of the segments to a certain degree, such changing the nozzle area. The inner ring is connected to converging nozzle segments and can move only forward or backward (not tilt). Since the inner ring is not separately controlled, it must be mechanically coupled via a cardan joint to the outer ring. The function of the cardan joint is accomplished by a middle ring which is connected to the outer ring through two bolts on the sides and to the inner ring through two bolts on the top and on the bottom. According to ITP the thrust vector control not only controls the nozzle area but also increases the thrust by seven to ten percent at speeds above Mach 1.2. The EJ2000 generates between 60 kN and 90 kN (with afterburning). Along with preparing the test bench trials, ITP and Dasa are working on a flyable design of a thrust vector nozzle. A decision on whether or not the Eurofighter will ever be equipped with thrust vector nozzles is still a long way off. Technically, the integration of the system is no problem since the nozzle is designed to fit in the existing engine bay. The changes would be limited to the hydraulic system, the flight control software, and some local reinforcements. Prize would supposedly be set at approximately one percent of the aircraft cost. From page 61 of FLUG REVUE 4/97 Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 4/97 Copyright 1997 by Motor-Presse Stuttgart. All rights reserved. Last updated March 7, 1997