TY  - JOUR
A1  - Dachwald, Bernd
A1  - Ulamec, Stephan
A1  - Postberg, Frank
A1  - Sohl, Frank
A1  - Vera, Jean-Pierre de
A1  - Christoph, Waldmann
A1  - Lorenz, Ralph D.
A1  - Hellard, Hugo
A1  - Biele, Jens
A1  - Rettberg, Petra
T1  - Key technologies and instrumentation for subsurface exploration of ocean worlds
JF  - Space Science Reviews
N2  - In this chapter, the key technologies and the instrumentation required for the subsurface exploration of ocean worlds are discussed. The focus is laid on Jupiter’s moon Europa and Saturn’s moon Enceladus because they have the highest potential for such missions in the near future. The exploration of their oceans requires landing on the surface, penetrating the thick ice shell with an ice-penetrating probe, and probably diving with an underwater vehicle through dozens of kilometers of water to the ocean floor, to have the chance to find life, if it exists. Technologically, such missions are extremely challenging. The required key technologies include power generation, communications, pressure resistance, radiation hardness, corrosion protection, navigation, miniaturization, autonomy, and sterilization and cleaning. Simpler mission concepts involve impactors and penetrators or – in the case of Enceladus – plume-fly-through missions.
Y1  - 2020
U6  - http://dx.doi.org/10.1007/s11214-020-00707-5
SN  - 1572-9672
N1  - Corresponding author: Bernd Dachwald
VL  - 216
IS  - Art. 83
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - JOUR
A1  - Finger, Felix
A1  - Götten, Falk
A1  - Braun, Carsten
A1  - Bil, Cees
T1  - Mass, primary energy, and cost: the impact of optimization objectives on the initial sizing of hybrid-electric general aviation aircraft
JF  - CEAS Aeronautical Journal
N2  - For short take-off and landing (STOL) aircraft, a parallel hybrid-electric propulsion system potentially offers superior performance compared to a conventional propulsion system, because the short-take-off power requirement is much higher than the cruise power requirement. This power-matching problem can be solved with a balanced hybrid propulsion system. However, there is a trade-off between wing loading, power loading, the level of hybridization, as well as range and take-off distance. An optimization method can vary design variables in such a way that a minimum of a particular objective is attained. In this paper, a comparison between the optimization results for minimum mass, minimum consumed primary energy, and minimum cost is conducted. A new initial sizing algorithm for general aviation aircraft with hybrid-electric propulsion systems is applied. This initial sizing methodology covers point performance, mission performance analysis, the weight estimation process, and cost estimation. The methodology is applied to the design of a STOL general aviation aircraft, intended for on-demand air mobility operations. The aircraft is sized to carry eight passengers over a distance of 500 km, while able to take off and land from short airstrips. Results indicate that parallel hybrid-electric propulsion systems must be considered for future STOL aircraft.
Y1  - 2020
U6  - http://dx.doi.org/10.1007/s13272-020-00449-8
SN  - 1869-5590
N1  - Corresponding author: Felix Finger
VL  - 2020
IS  - 11
SP  - 713
EP  - 730
PB  - Springer
CY  - Heidelberg
ER  -