NASA Technical Reports Server (NTRS) 20070002619: Aerocapture Benefits to Future Science Missions

24.6 MB·English

by  NASA Technical Reports Server (NTRS)

Source of Acquisition
NASA Marshall Space Flight Center
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Gwen Artis
Bonnie James
NASA’s In-Space Propulsion Technology (ISPT) Program is investing in technologies to
revolutionize the robotic exploration of deep space. One of these technologies is
Aerocapture, the most promising of the “aeroassist~t’e chniques used to maneuver a space
vehicle within an atmosphere, using aerodynamic forces in lieu of propellant. (Other
aeroassist techniques include aeroentry and aerobraking.) Aerocapture relies on drag
atmospheric drag to decelerate an incoming spacecraft and capture it into orbit. This
technique is very attractive since it permits spacecraft to be launched from Earth at higher
velocities, providing shorter trip times and saving mass and overall cost on future
missions.
Recent aerocapture systems analysis studies quantify the benefits of aerocapture to future
exploration. The 2002 Titan aerocapture study showed that using aerocapture at Titan
instead of conventional propulsive capture results in over twice as much payload
delivered to Titan. Aerocapture at Venus results in almost twice the payload delivered to
Venus as with aerobraking, and over six times more mass delivered into orbit than all-
propulsive capture. Aerocapture at Mars shows significant benefits as the payload sizes
increase and as missions become more complex. Recent Neptune aerocapture studies
show that aerocapture opens up entirely new classes of missions at Neptune.
Current aerocapture technology development is advancing the maturity of each sub-
system technology needed for successful implementation of aerocapture on future
missions. Recent development has focused on both rigid aeroshell and inflatable
aerocapture systems. Rigid aeroshell systems development includes new ablative and
non-ablative thermal protection systems, advanced aeroshell performance sensors,
lightweight structures and higher temperature adhesives. Inflatable systems such as
trailing tethered and clamped “ballutes” and inflatable aeroshells are also under
development. Computational tools required to support future aerocapture missions are an
integral part of aerocapture development. Tools include engineering reference
atmosphere models, guidance and navigation algorithms, aerothermodynamic modeling,
and flight simulation.

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