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Instrumentation that has been used for characterization of mixed-phase and glaciated conditions in the past, like the OAP probes, are subject to errors caused by variations in diffraction on the images away from the object plane and by the discrete nature of their particle detection and sizing. Correction methods are necessary to consider their measurements adequate for high ice water content (IWC) environments judged to represent a significant safety hazard to propellers and turbofan engine operability and performance. For this reason, within the frame of EU FP7 HAIC project, instrumentation characterization and validation is considered a major element need for successful execution of flight tests campaigns. Clearly, instrumentation must be sufficiently reliable to assess the reproducibility of artificial clouds with high ice water content generated in icing tunnels.

The French-Indian MEGHA-TROPIQUES satellite is devoted to the atmospheric research. Data collected by the satellite will improve our knowledge on the water cycle contribution to the climate dynamic in the tropical atmosphere and our understanding of the processes linked to the tropical convection. The payload is made of MADRAS (developed by CNES and ISRO) and of two instruments provided by CNES: SAPHIR and SCARAB. The paper presents: the thermal control design of the two CNES instruments SAPHIR and SCARAB, taking into account the mechanical and scientific constraints. This design is based on a passive thermal control, on uses of heating power for cold cases or safe mode. This thermal design is today analyzed and the main results will be shown; the validation logic is now defined and instrument thermal tests are in preparation. These instrument thermal tests will be done in the second part of 2008.

The Netlander mission aims to deploying on the surface of Mars a network of 4 landers, which will perform simultaneously measurements in order to study the internal structure of Mars, its sub-surface and its atmosphere. This paper describes the phase B thermal control concept of the Netlander Surface Module, taking into account various thermal environments from the cruise to Mars phase until the landing and the one Martian year phase on the Mars surface. The paper focuses on two specific thermal tests. The first one is a thermal conductivity measurement of three pre-selected insulation materials in a 6 - 10 hPa CO2 environment, and the second one is a performance test of a Loop Heat Pipe designed to comply the Netlander Surface Module needs. This paper is mainly derived from the report referenced ref. 1.

The INTERnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) is an ESA observatory scientific satellite which was successfully launched on the 17th of October 2002. The payload consists in four instruments : an optical camera (OMC), a X-ray monitor (XRM), an imager (IBIS) and a spectrometer (SPI). The spectrometer (20 keV-8 MeV energy range, 2.3 m high, 1.1 m diameter, around 1300 kg) has been supplied by CNES where this instrument has been managed, assembled and tested before delivery to ESA for satellite level activities. This paper describes the spectrometer flight model thermal design achieved thanks to the different international partners, gives and overview of the cryostat used to cool down the detection plane and exposes the thermal validation plan used at instrument level (thermal mathematical model and thermal test philosophy, cryostat thermal validation). We then focus on in-flight performances and compare them to expected ones.

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization.

This study presents the results of the ICE GENESIS 2021 Swiss Jura Flight Campaign in a way that is readily usable for ice accretion modelling and aims at improving the description of snow particles for model inputs. 2D images from two OAP probes, namely 2D-S and PIP, have been used to extract 3D shape parameters in the oblate spheroid assumption, as there are the diameter of the sphere of equivalent volume as ellipsoid, sphericity, orthogonal sphericity, and an estimation of bulk density of individual ice crystals through a mass-geometry parametrization. Innovative shape recognition algorithm, based on Convolutional Neural Network, has been used to identify ice crystal shapes based on these images and produce shape-specific mass particle size distributions to describe cloud ice content quantitatively in details. 3D shape descriptors and bulk density have been extracted for all the data collected in cloud environments described in the regulation as icing conditions.

Measurements in snow conditions performed in the past were rarely initiated and best suited for pure and extremely detailed quantification of microphysical properties of a series of microphysical parameters, needed for accretion modelling. Within the European ICE GENESIS project, a considerable effort of natural snow measurements has been made during winter 2020/21. Instrumental means, both in-situ and remote sensing were deployed on the ATR-42 aircraft, as well as on the ground (ground station at ‘Les Eplatures’ airport in the Swiss Jura Mountains with ATR-42 overflights). Snow clouds and precipitation in the atmospheric column were sampled with the aircraft, whereas ground based and airborne radar systems allowed extending the observations of snow properties beyond the flight level chosen for the in situ measurements.

Composite materials are increasingly being used in the manufacturing of structural components in aeronautics industry. A consequent light-weight design of CFRP primary structures requires adhesive bonding as the optimum joining technique but is limited due to a lack of adequate quality assurance procedures. The successful implementation of a reliable quality assurance concept for adhesive bonding within manufacturing and in-service environments will provide the basis for increased use of lightweight composite materials for highly integrated aircraft structures thus minimizing rivet-based assembly. The expected weight saving for the fuselage airframe is remarkable and therefore the driver for research and development of key-enabling technologies. The performance of adhesive bonds mainly depends on the physico-chemical properties of adherend surfaces.

The simulation of natural-like snow conditions in a controlled environment such as an Icing Wind Tunnel (IWT) is a key component for safe, efficient and cost-effective design and certification of future aircraft and rotorcraft. Current capabilities do not sufficiently match the properties of natural snow, especially in terms of size and morphology. Within the Horizon 2020 project ICE GENESIS, a new technology has been developed aiming to better recreate natural snowflakes. The focus of the newly developed system was the generation of falling snow in a temperature range of +1°C to -4°C. Ground measurements and flight test campaigns have been performed to better characterize these conditions and provide requirements for wind tunnel facilities. The calibration results of the new snow generation system as well as snow accretion data on a NACA0012 test article with a chord length of 0.377 m are presented.

This paper presents the design, testing and analysis of the 5kW ammonia Capillary Pumped Two Phase Loop (CPL), developed in co-operation between MATRA MARCONI SPACE (MMS) and the French Space Agency (CNES). The ammonia CPL breadboard was designed to transport a 5 kW heat load over 5 meters. It consisted of: 5 parallel evaporators and isolators, 4 parallel condensers with an additional sub-cooler, a reservoir, to control the loop saturation temperature, two adiabatic pipes, one for the liquid line and one for the vapour line the testing instrumentation including thermocouples and absolute and differential pressure transducers.

COROT mission is managed by CNES (French National Space Agency) in association with three major French laboratories (LAM, LESIA, IAS) and several European countries, contributing to the payload and the ground segment. This astronomy mission objectives are astero-seismology as well as planet finding. The COROT spacecraft is based on a PROTEUS low Earth orbit recurrent platform, developed by CNES and Alcatel Alenia Space. It was injected on 27th December 2006 at a 898 km polar and circular orbit by a Soyuz launcher and is being operated from CNES-Toulouse. This paper focuses on the thermal control design and first in-orbit performances of the payload which mainly consists in an afocal telescope, a wide field camera with cooled CCDs, and an equipment bay. Largely using standard and well-proven technologies, this paper also points out some thermal control specificities and techniques used.

Electrodialysis (ED) is an electrically driven process that operates at ambiant temperature and pressure. It is of interest for removing ionized molecules, and reconcentrating them, specially at medium and low concentration. It is always used in association with other membrane technologies and/or pretreatment. It is of high interest to simulate the contact of ED membranes with candidate stabilizing or cleaning agents in a water recycling system. We selected among a large and representative range of commercial anionic and cationic membranes, 20 different ED membranes and tested them regarding their resistance to 5 chemical agents. The samples were immerged in the solution (480 h / 60 °C), and a physical characterisation was performed: dimensional stability, measure of electrical resistance, determination of exchange capabilities. Four membranes presented acceptable performances after contact with hydrogen peroxyde (300 ppm) regarding electrical resistance.