Taverny Air Base (formerly ''Base Aérienne 921 "Frères Mahé" de Taverny'') is located in the communities of Taverny and Bessancourt in the Val d'Oise département of

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

, twenty kilometers north of

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

. Until 2011 it was the headquarters of the nuclear strike force of the

French Air Force The French Air and Space Force (, , ) is the air force, air and space force of the French Armed Forces. Formed in 1909 as the ("Aeronautical Service"), a service arm of the French Army, it became an independent military branch in 1934 as the Fr ...

, with an underground command center. The base is divided into three tiers with an area of approximately 15 hectares: *The first tier is underground in a former

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate Hydrate, dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, drywall and blackboard or sidewalk ...

quarry A quarry is a type of open-pit mining, open-pit mine in which dimension stone, rock (geology), rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some juri ...

beneath the Forest of Montmorency. The facility comprised the hardened command facility for the French Air Force. *The second tier is on the surface, and provided support services for the underground command center. *The third tier is at the top of the hill, with facilities for secure military communications. There were no aviation facilities apart from a heliport.

Description

The base is located on the flank of the heights of the community of Taverny, with the hardened facility between 70 and 80 meters below the surface in the former quarries. The tunnels are large enough for trucks to enter. The underground climate is described as warm and dry, but the tunnels require monitoring for water penetration and dissolution of the gypsum. Somewhat more than 1000 personnel are employed at the base. The facility is provided with backup power and an independent water supply. A 2000m²

Faraday Cage A Faraday cage or Faraday shield is an enclosure used to block some electromagnetic fields. A Faraday shield may be formed by a continuous covering of conductive material, or in the case of a Faraday cage, by a mesh of such materials. Faraday cag ...

was completed in 1993 after six years of construction Magazine ''Vivre en Val-d'Oise'', n°92, juin-juillet-août 2005, p 50. - one of the largest in Europe.

History

* 1815: First commercial exploitation as a gypsum quarry. * 1941-1944: During

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, the German occupiers converted some of these tunnels for industrial use. The SKF

ball bearing A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this ...

factory was moved there from south of Paris. At the time of the Allied invasion, the manufacture of ball bearings had been started. The two main tunnels were connected and an entrance structure with gates was constructed. Before their evacuation of Paris, the

Germans Germans (, ) are the natives or inhabitants of Germany, or sometimes more broadly any people who are of German descent or native speakers of the German language. The Basic Law for the Federal Republic of Germany, constitution of Germany, imple ...

destroyed the equipment in the tunnels. Several places in the area of the plant show evidence of fire. According to a villager, the Germans used oil fires to destroy the equipment. This caused cracking and falling rocks. Mines and booby traps were left behind in the tunnels and the nearby woods; these were removed, along with the remains of the plant, by the

U.S. Army The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United Stat ...

. There is no evidence that the Allies bombed the tunnels during the occupation. * 1946: The French Air Force used the quarry as a depot. * 1957: The creation of the Air Defense Operations Center (''Centre d'Opération de la Défense Aérienne'' - CODA). * 1961: The creation of the Territorial Air Defense Staff (''Etat-major de la Defense Aérienne du Territoire'' - DAT) and the Air Force Air Defense Command (''Commandement Air des Forces de Défense Aérienne'' - CAFDA). These organizations were dissolved in 1994 and replaced with the Air Defense and Air Operations Command (''Commandement de la Défense Aérienne et des Opérations Aériennes'' - CDAOA) and its Air Operations Center (''Centre de Conduite des Opérations Aériennes'' - CCOA). * 1963: Creation of BA921, attached to the 2nd Air Region, and the installation on the surface of the

Strategic Air Forces Command The Strategic Air Forces (FAS) () is a command of the French Air and Space Force. It was created on January 14, 1964, and directs France's nuclear bombardment force. The headquarters was formerly at Taverny Air Base, but has now moved to Véli ...

(''Commandement des Forces Aériennes Stratégiques'' - CFAS). * 1967: Installation of the Strategic Forces Operations Center (''Centre d'Opérations des forces stratégiques'' - COFAS) underground. * 1988: BA921 takes the name "Frères Mahé" ("Brothers Mahé" in English) in homage to three brothers killed in the command of their aircraft. * 1992: Installation of the Special Operations Command ('' Commandement des Opérations Spéciales'' - COS). * 2000: BA921 was attached to the Northern Air Region. * 2006: Special Operations Command (COS) moves to BA107 at Villacoublay. * 2007: The Air Operations Center moves to BA942 at Lyon Mont-Verdun. At the same time, the Air Defense and Air Operations (CDAOA) moves to BA117 in Paris and the Air Information Center (''Centre de Renseignement Air'' - CRA) moves to BA128 at

Metz Metz ( , , , then ) is a city in northeast France located at the confluence of the Moselle (river), Moselle and the Seille (Moselle), Seille rivers. Metz is the Prefectures in France, prefecture of the Moselle (department), Moselle Departments ...

. * 2011: BA 921 is disestablished on 5 July 2011. * 2020 : In the spring of 2020, it is decided to relocate the headquarters of the Strategic Air Forces on the base, i.e. a hundred people plus the ancillary services in 2024

Nuclear deterrent

Taverny provided information to the following organizations: * The commander of the strategic air forces (''Commandement des forces aériennes stratégiques'' - CFAS), which constitute one leg of France's

nuclear deterrent Nuclear strategy involves the development of doctrines and strategies for the production and use of nuclear weapons. As a sub-branch of military strategy, nuclear strategy attempts to match nuclear weapons as means to political ends. In addit ...

. * The Analysis and Simulation Center for the Preparation of Air Operations (''Centre d'Analyse et de Simulation pour la Préparation des Opérations Aérienne'' - CASPOA). * The Military Air traffic Control (''Direction de la Circulation Aérienne Militaire'' - DirCAM). * The Meteorology Center for External Operations (''Centre de Météorologie des Opérations Extérieures'' - CMOE)

Other facilities

A similar Air Force facility exists northwest of

Lyon Lyon (Franco-Provençal: ''Liyon'') is a city in France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of the French Alps, southeast of Paris, north of Marseille, southwest of Geneva, Switzerland, north ...

at BA942 Lyon-Mont Verdun. The

French Navy The French Navy (, , ), informally (, ), is the Navy, maritime arm of the French Armed Forces and one of the four military service branches of History of France, France. It is among the largest and most powerful List of navies, naval forces i ...

's counterpart facility, controlling the

ballistic missile submarine A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their nuclear deterrence capabi ...

strike force (''

Force océanique stratégique The Strategic Ocean Force () is one of two terms that describe the submarine component of the French Navy. Prior to 1999, FOST grouped ballistic missile submarines with a role in France's nuclear deterrent. Since 1999, they have been integrated ...

'' - FOST), was located about 20 km to the south at Houilles,

Yvelines Yvelines () is a department in the western part of the Île-de-France region in Northern France. In 2019, it had a population of 1,448,207.French Air and Space Force bases Nuclear bunkers in France Nuclear command and control Emergency management in France Nuclear weapons program of France Buildings and structures in Val-d'Oise Continuity of government Cold War sites in France