[9] In the spring of 1935, Paul Badré was transferred (at the same time as Constantin Rozanoff) to the Aircraft test center of the Villacoublay Air Base.

At the time of the Munich Agreement, in September 1938, he carried out a reconnaissance mission for the Secret Intelligence Service and the “Air” section of the Deuxième Bureau (commanded by his friend Georges Ronin).

In the spring of 1940, at the request of the Air Staff, he visited bomber squadrons in the South-West of France to monitor pilot training on Leo 45.

[13][14] In March 1941, Frederick Winterbotham (codename Summer), a Royal Air Force and MI6 officer in charge of the Ultra intelligence, sent Ronin's network transceivers concealed in diplomatic bags.

Badré obtained from Colonel Jean Touzet du Vigier[17] that weapons be secretly delivered in the occupied zone to Ceux de la Libération and Alfred Heurteaux's resistance network.

[18] In the spring of 1942, PTT engineer Robert Keller[19] and his team were able to tap German telephone communications between Paris and Berlin, intercepting the exchanges of high-ranking Kriegsmarine, Luftwaffe, Wehrmacht Heer and Gestapo officials.

Ronin’s organization was also put in touch by Count Potocki with the Polish service of Stanisław Gano, for whom a second link with London was set up.

In early October, Paul Badré was summoned by General Revers (Chief of the Defence Staff) who warned him that, with Pierre Laval's agreement, the Abwehr and the Gestapo were preparing to send mobile teams into the free zone, to identify clandestine posts using radio direction finding.

On the night of November 9-10, 1942, hours before the invasion of the free zone, the main officers of Ronin's network flew to Algeria on two Dewoitine D.338 provided by General d’Harcourt.

[24] Colonel Ronin sided with General Giraud and took command of the Secret Service alongside Louis Rivet and Paul Paillole.

Upon his return to Algiers on January 3, 1943, he appointed Major Badré as liaison officer with MI6 and colonel Passy’s BCRA (General de Gaulle's intelligence service).

[26] Initially housed in Albemarle Street, in Claude Dansey’s apartment[27] (where he made the acquaintance of Colonel Passy), MI6 then moved him to a villa near Wimbledon Common.

It was only at the end of June that his group became operational, after the delivery by the United States Army Air Forces of 16 brand new Martin B-26 Marauder.

On August 15, the first day of Operation Dragoon, 72 bombers (36 from the French Liberation Army and 36 American Flying Fortresses) had the mission to destroy bridges over the Buëch and the Durance.

The weather was unfavorable and during a manoeuvre to avoid a collision, a USAAF pilot accidentally dropped several bombs on the town of Sisteron, causing the death of about 100 civilians.

[38] On August 1, 1945, Paul Badré was the first Frenchman to fly a jet aircraft (a german Messerschmitt Me 262) on national territory, during the inauguration of the Brétigny-sur-Orge flight test center.

He was also on the board of Ratier Figeac (1962–1979) and Jean Bertin’s company (1965–1981), whose Aérotrain project was set aside by the French government following the 1973 oil crisis.