Yves Sillard

Yves Sillard is a French engineer and senior civil servant who served as director-general of CNES, the French national space agency, from 1976 to 1982, a period during which he provided the institutional authority necessary to establish GEPAN (Groupe d'Étude des Phénomènes Aérospatiaux Non-identifiés) in May 1977, formally embedding UFO investigation within a national space agency, an arrangement with no direct equivalent anywhere else in the world at the time. Sillard's broader career extended well beyond UFO matters, including later senior roles overseeing French defense procurement as head of the Délégation générale pour l'armement (DGA) and other high-level state technical administration positions, reflecting the seriousness with which the French state establishment, in contrast to the more adversarial U.S. Air Force posture under Project Blue Book, approached the institutional question of who should be responsible for UFO data. Though not himself a hands-on case investigator in the manner of Claude Poher or Jean-Jacques Velasco, Sillard's administrative decision to house GEPAN within CNES rather than dismiss the subject or relegate it to a marginal advisory committee is widely credited by historians of French ufology as the single most consequential institutional choice underlying the program's decades-long continuity through its GEPAN, SEPRA, and present-day GEIPAN incarnations, which remain active within CNES to this day.