Caltech Logo

GALCIT Colloquium

Friday, October 25, 2019
3:00pm to 4:00pm
Add to Cal
Guggenheim 133 (Lees-Kubota Lecture Hall)
Exomars 2016 Entry Flight and Achievements of its Aerothermal Instrumentation Package COMARS+
Ali Guelhan, Professor, German Aerospace Center, DLR,

The ExoMars 2016 mission, led by ESA, has been launched by the Russian Proton on March 14th, 2016. The mission consists of the Trace Gas Orbiter (TGO) and the Entry, Descent, and Landing Demonstrator Module (EDM, named Schiaparelli), both supplied by ESA. Schiaparelli separated from TGO on October 16th, 2016, and reached Mars 3 days later. It successfully entered with a pre-defined flight path angle and performed a nominal hypersonic entry, decreasing its velocity until reaching the subsonic regime under the parachute. An anomaly occurred during the descent phase the EDM led to an earlier separation of the backshell from the landing module and the failure of Schiaparelli shortly before landing. During the EDL, Schiaparelli was able to communicate with the TGO and with the Mars Reconnaissance Orbiter, transmitting its real-time onboard telemetry and collecting valuable data wrt to flight properties of the vehicle.

The instrumentation package COMARS+ was developed to measure aerothermal parameters on the back cover of the ExoMars Schiaparelli lander during Martian entry. The aerothermal sensors called Combined Aerothermal and Radiometer Sensor (COMARS) combine four discrete sensors, measuring static pressure, total heat flux, temperature, and radiative heat flux. A subset of the COMARS flight data was transmitted in real-time during the entry and was received by the ExoMars 2016 orbiter, except the plasma blackout phase. The radiative heat flux on the back cover close to the vehicle shoulder was measured successfully for the first time on a Mars entry vehicle. These measurements confirm recent findings that radiative heating can be a significant portion of total heating on the back cover during Mars entry. The comparison between COMARS data and heat fluxes determined from the thermocouple data of thermal plugs of the industrial partner show reasonable agreement. This data combined with the front surface aerothermal data is used to understand the entry flight features. Furthermore, a post-flight analysis has been carried out for the reconstruction of atmospheric density and determination of flight angles using the FADS approach.

For more information, please contact Benedikt Barthel by email at bbarthel@caltech.edu.