- strumentazione aerodinamica e aerotermodinamica;
- protezioni termiche e strutture calde; l'IXV è dotato di una vasta gamma di sistemi di protezione termica (materiali, concetti) come compositi ceramici e materiali ablativi per misurare le loro prestazioni in condizioni di volo reali;
- controllo di volo ipersonico: guida, navigazione e controllo, motori di controllo di assetto e superfici di controllo aerodinamico; l'IXV è il primo veicolo spaziale europeo controllato da una combinazione di flap e propulsori implementati utilizzando algoritmi di guida avanzati basati su dati inerziali e ricevitori GPS;
- modellizzazione dei fenomeni aerodinamici e termici che si verificano durante il rientro atmosferico il cui controllo ridurrebbe i margini di sicurezza incorporati nel progetto di questo tipo di veicolo.
- il progetto PRIDE, che prevede la costruzione di uno spazioplano sperimentale;
- l'ISV, che adotterà molte delle scelte tecniche usate nell'IXV e basato sui risultati ottenuti dal suo volo sperimentale;
- il Centro italiano ricerche aerospaziali e Thales Alenia Space stanno sviluppando il progetto Space Rider, un velivolo spaziale riutilizzabile, evoluzione dell'IXV, in grado di effettuare un rientro atmosferico a Terra.
- analizzare l'interazione aerotermodinamica nel volo ipersonico tra un veicolo di questa tipologia "lifting body" e il plasma atmosferico,
- studiare il comportamento dei materiali speciali nella resistenza e nello smaltimento del calore e infine valutare il controllo e la stabilità dell'assetto durante il rientro rappresentano il valore aggiunto della missione.
ENGLISH
The Intermediate eXperimental Vehicle (IXV) is a programme of the European Space Agency aimed at building an experimental spacecraft capable of making a controlled atmospheric re-entry from low Earth orbit (about 300 km). The vehicle performed its first unmanned flight test in February 2015, passing the main tests of atmospheric re-entry manoeuvre and thermal protection.
Project history
IXV is an ESA project that aims to validate atmospheric re-entry technologies within the FLPP programme. This technological research programme focuses on the development of technologies for future European launchers. PPBM is at the origin of the Atmospheric Re-entry Demonstrator (ARD) launched in 1998. The IXV, equipped as a flying laboratory, performs re-entry, aerodynamically controlled, in which various data will be stored.
The objectives of the IXV are to develop tools and processes implemented during atmospheric re-entry:
aerodynamic and aerothermodynamic instrumentation;
thermal protection and hot structures; the IXV is equipped with a wide range of thermal protection systems (materials, concepts) such as ceramic composites and ablative materials to measure their performance in real flight conditions;
hypersonic flight control: guidance, navigation and control, attitude control engines and aerodynamic control surfaces; the IXV is the first European spacecraft controlled by a combination of flaps and thrusters implemented using advanced guidance algorithms based on inertial data and GPS receivers;
modelling of aerodynamic and thermal phenomena occurring during atmospheric re-entry whose control would reduce the safety margins incorporated in the design of this type of vehicle.
The development of the IXV is based on previous studies, such as the CNES (the French space agency) called Pre-X and the ESA's Atmospheric Reentry Experimental Vehicle (AREV). The first phases of the vehicle's development were managed by NGL Prime SpA, a joint venture of EADS SPACE (70%) and Finmeccanica (30%). Phase C (finalisation of the design) was assigned to Thales Alenia Space, at its Turin headquarters.
Technical characteristics
The IXV is a wing-less carrier body with two Flaps fixed in the fuselage extension to control flight during atmospheric re-entry. The re-entry is conducted keeping the nose high, just like for the Space Shuttle, while the final phase of the descent is completed with a chain of parachutes ejected from the top of the vehicle. The spacecraft is 5 m long, 1.5 m high and 2.2 m wide with a mass of 2 tons. To control the flight profile, the IXV uses its two flaps and four 400 N thrust rocket motors positioned at the rear of the transport body. These thrusters have already been implemented on the upper floors of the Ariane 5 launcher and are liquid propellant (hydrazine). To satisfy its purpose as a technological demonstrator, the IXV is equipped with almost 250 sensors positioned at different points on the hull surface: 37 pressure sensors, 194 temperature sensors, 12 displacement sensors and 48 sensors that measure the forces suffered by the nacelle or other data such as the infrared camera positioned at the rear. These sensors are divided into two sub-sets: those used to analyse the aerodynamics of the vehicle and those affected by thermal stress.
Test flight
The launch, which took place using the new European light launcher Vega, was initially planned to take place by 2013 and was then successfully completed on 11 February 2015. It departed from Korou at 1:40 pm, at an altitude of 320 km, the spacecraft detached from the launcher and flew up to 450 km at a speed of about 7.5 km/s and began descending towards the Pacific Ocean at an altitude of 120 km. The entire flight lasted 1 hour and 39 minutes, during which a great deal of data was collected on the flight and descent.
Related projects
In parallel, the European Space Agency is pursuing the PRIDE project, which involves the construction of an experimental space plane, the ISV, which will adopt many of the technical choices used in the IXV and based on the results obtained from its experimental flight.
The Italian Aerospace Research Centre and Thales Alenia Space are developing the Space Rider project, a reusable space aircraft, an evolution of the IXV, capable of atmospheric re-entry to Earth.
The flight of the European spaceplane IXV
The European Space Agency ESA has tested the IXV (Intermediate Experimental Vehicle) atmospheric re-entry demonstrator which, after a suborbital parabola of 101 minutes, successfully landed in the Pacific Ocean.
The mission had started at 14.40 Italian time with the take-off, on board a Vega carrier, from Kourou spaceport in French Guiana. Having reached an altitude of 340 km, the IXV separated from the last stage of the launcher, continuing in free flight to an altitude of 412 km, after which it began its re-entry into the atmosphere. The spaceplane controlled its attitude thanks to two special rear ailerons, gliding and slowing down as it crossed the increasingly dense layers of the atmosphere. At an altitude of 26 km, the braking sequence began with a parachute until it landed in the ocean, where the IXV was recovered by the deep-sea tug Nos Aries of the Livorno-based Neri group.
The re-entry phase was the main object of this test, in fact more than 300 sensors recorded a large amount of data that are analyzed immediately afterwards. "It is a great day for the European Space and a great day for Italy", said the President of the Italian Space Agency in Kourou after the splashdown.
The ASI and national industry have played a major role as the IXV programme is led by the Italian Giorgio Tumino, the space plane was built in Turin at Thales Alenia Space, the mission control is also in Turin at ALTEC (Advanced Logistics Technology Engineering Center), and the same can be said of the VEGA vector in whose implementation Italy is the largest contributor with 65%.
The data obtained are indispensable for the implementation of the PRIDE programme (Programme for Reusable In-orbit Demonstrator for Europe), which will see the development of a mini-shuttle (similar to USAF's X-37/B) with the capacity to perform orbital missions and glide landings.
The launch is almost entirely made in Italy
The launch of the European space vehicle IXV (Intermediate eXperimental Vehicle) was a success as everything went smoothly.
The spaceplane, one of the possible heirs of the Space Shuttle and the first European vehicle to be designed to return to Earth, took off aboard a Vega rocket from the European base in Kourou (French Guiana) to complete its first low orbit flight mission 100 minutes later, with a ditching in the Pacific.
The programmes of the IXV spacecraft and the VEGA launcher were carried out by the European Space Agency thanks to the significant technical and financial contribution of the Italian Space Agency. The launcher, which was designed and built in Italy by ELV & AVIO, is "made in Italy", as is the experimental IXV spacecraft, also designed and built in Turin by a pool of expertise led by Thales Alenia Space Italia with contributions from CIRA (Italian Aerospace Research Centre - Experimentation, aerothermodynamics, drop test support and launch operations), SELEX (Power Distribution Unit), Alenia Aermacchi (Avionics and software), AVIO (ablative thermal protection), a number of Italian universities, CNR/INSEAN and many small and medium-sized national companies. Italiano is the control centre of ALTEC in Turin, which managed and monitored all the flight operations of the IXV spacecraft, but also one of the ground stations that followed the flight, that of Malindi, managed by the Italian Space Agency. The NOS ARIES ship that carried out the recovery is Italian and, last but not least, it is worth mentioning the technological contribution made by Telespazio to the ground segment with the communication network: the Italian flag dominates in this European mission. This is the first sub-orbital controlled re-entry experiment of a spacecraft into the atmosphere by Europe, which is fundamental for studying the stability and attitude control characteristics of the aircraft and the aerothermodynamic characteristics: something that is still a subject of experimentation for Europe today, because the other countries that have developed similar technologies (the Soviet Union and the United States first and foremost since the 1960s, and more recently China and India) do not share, for obvious reasons of confidentiality, their own scientific and technological knowledge of the delicate atmospheric re-entry phase. The success of this mission also confirms the reliability and versatility of the VEGA launcher: unlike previous launches, VEGA released the IXV at a sub-orbital altitude of about 330 km.
Finally, for the first time it launched itself towards the equator, while in the past it launched with quasi-polar trajectories. It was necessary to verify some telemetry measurements from the ground. This led to the suspension and then the resumption of operations in safety.
A demanding phase of analysis is now underway at the CIRA of the scientific data recorded by IXV during the re-entry phase:
Analyse the aerothermodynamic interaction in hypersonic flight between a vehicle of this type "lifting body" and atmospheric plasma,
studying the behaviour of special materials in resistance and heat dissipation and finally assessing the control and stability of the trim during re-entry represent the added value of the mission.
The experimental data acquired with this mission and their analysis are the fundamental elements for the design and implementation of possible future European re-entry systems such as, for example, the PRIDE programme that Italy is carrying out with the technical and scientific support of ASI and CIRA.
A decision has recently been taken to finance the PRIDE programme, which provides for the development of technologies for the development of automatic ground return space vehicles.
CIRA, on the strength of the relevant technological and scientific experience gained in the Unmanned Space Vehicle and IXV programmes, will certainly play a leading role in the forthcoming developments of European "space planes”.
