Modular, flexible and competitive, Ariane 6 is intended to offer the best space launch solution, by 2020, to commercial and institutional customers. Therefore it can’t anymore rely on legacy inertial reference. Advanced solutions were requested through an open tender conducted by ArianeGroup under European Space Agency (ESA) supervision. SpaceNaute®, the Safran solution based of HRG technology, was then selected against RLG and FOG based solutions proposed by the competitors. This paper describes the trade-off studies conducted to select the proper technology and describe the unique SWaP (Size, Weight and Power) breakthrough of SpaceNaute®, unveils key performance characteristics of the inertial sensors for SpaceNaute® and how HRG benefits are capitalized into the product