The hydraulic system in a fighter aircraft is not fully utilised during large parts of the flight mission were more electrical power is needed. To better utilise the hydraulic power the current Auxiliary Hydraulic Pump (AHP) and the Emergency Hydraulic Pump (EHP) can be exchanged to an Electro Hydraulic Energy Converter (EHEC). The EHEC has the possibility to provide hydraulic power to the system, but also convert hydraulic power into electric power. The control for such a unit can be implemented in different ways. A literature study was performed to decide a suitable architecture for use in a fighter aircraft application. A simulation model representing the resulting architecture was created. The simulation model was successful in describing the basic behaviour of the hydraulic system, but lacks a realistic representation of hydraulic consumers.  Different control strategies were created and tested on the simulation model with several test scenarios based on real flight data from tests performed on the aircraft. The control strategies were compared and suitable candidates were presented based on their relative performance and compared with the current hydraulic system behaviour. An architecture consisting of a variable displacement pump with over-center capabilities combined with a permanent magnet synchronous machine (PMSM) was decided to be used. A PI-controller with a feedforward on consumer flow was the best performing controller for use in emergency operation of the EHEC. For the case when regenerating electrical power a PI-controller with load pressure feedback is desired initially during start up. When reaching steady state a PI-controller without load pressure feedback is then advantageous.

The objective of this study was to design a launch vehicle capable of deploying a nanosatellite into a Sun-synchronous orbit at 500 km orbital altitude from the JAS 39E/F Gripen fighter aircraft. This was achieved by first performing theoretical calculations for the required nozzles and solid propellant grain configurations for the first two solid stages, followed by the necessary liquid propellant configuration for the third stage. Lastly, two methods were investigated in solving the trajectory ascent problem for the launch vehicle design. First, by stating the trajectory problem as an initial value problem while guessing a Sigmoidal steering law. Secondly, by stating the trajectory problem as a boundary value problem. The latter was solved by transcribing the trajectory problem into a nonlinear program where a parametric steering law was derived using a Sequential quadratic programming algorithm.Ultimately, resulting in a launch vehicle design with a gross lift-off mass of 1,289 kg, capable of launching an 8.4 kg payload into the targeted orbit, with suggested modifications to increase the possible payload mass to 12.9 kg. / Målet med den här studien var att designa en luftlanserad trestegsraket kapabel till att transportera en nanosatellit upp till en solsynkron omloppsbana på 500 km altitud från ett JAS 39E/F Gripen jaktflygplan. Det gjordes genom att först beräkna de nödvändiga dysorna och krutladdningsformerna för de två första stegen tillsammans med en flytande bränsledesign för det tredje steget. Två metoder undersöktes för bananalysen. Först genom att anta en Sigmoidal styrningsfunktion för pitchen, sedan genom att transkribera problemet till ett icke-linjärt program där en parametrisk styrlag togs fram genom att använda en Sequential quadratic programming algoritm. Slutligen presenterades en raketdesign med en total vikt på 1 289 kg, kapabel till att skjuta upp en nyttolast på 8,4 kg till den önskade omloppsbanan tillsammans med förslag som kan öka den möjliga nyttolasten till 12,9 kg.