The Advanced Reentry Demonstrator (ARD) was a European Space Agency (ESA) suborbital reentry vehicle. It was developed and operated for experimental purposes, specifically to validate the multiple reentry technologies integrated upon it and the vehicle's overall design, as well as to gain greater insight into the various phenomenon encountered during reentry.
The ARD only performed a single spaceflight. On 21 October 1998, the vehicle was launched upon the third flight of the Ariane 5 expendable launch system. Reaching a recorded altitude of 830 km, the ARD performed a guided reentry back to Earth before splashing down relatively close to its intended target point in the Pacific Ocean after one hour and 41 minutes of flight. Following its recovery and subsequent analysis, the vehicle was found to have performed well, the nose cone and heat shield thermal protection having remaining in an ideal state and having remained completely airtight and perfectly intact.
The ARD was the first guided sub-orbital reentry vehicle to be manufactured, launched and recovered by Europe.[1][2] One of the core purposes of the mission was the gathering of knowledge that could be subsequently used during the development of future re-entry vehicles and precise landing capabilities. In the aftermath of the programme, the ESA decided to embark on a follow-up reentry demonstrator, known as the Intermediate eXperimental Vehicle (IVX). The first IXV vehicle underwent its first successful test flight during February 2015. The ARD and IVX demonstrators are intended to serve as developmental stepping stones towards a vehicle called Space Rider, meant to be the first of a series of production-standard spaceplanes.
ARD ESA
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