Rüffler was born on 18 January 1918 in Waldenburg, present-day Wałbrzych in Poland, at the time in the Province of Lower Silesia within the German Empire.

Following flight training,[Note 1] he was posted to the Ergänzungsgruppe of Jagdgeschwader 3 (JG 3—3rd Fighter Wing) on 28 September 1940.

These air elements supported Generalfeldmarschall Gerd von Rundstedt's Heeresgruppe Süd (Army Group South), with the objective of capturing Ukraine and its capital Kiev.

The Gruppe spent one-month training in northern Germany before they arrived at the Schiphol airfield near Amsterdam in the Netherlands on 12 September.

[4] While based at Uetersen Airfield, Rüffler joined the Gruppe which received the Messerschmitt Bf 109 G-6 and was equipped with Y-Control for fighters, a system used to control groups of fighters intercepting United States Army Air Forces (USAAF) bomber formations.

[7] On 24 February 1944, the USAAF Eighth and Fifteenth Air Force attacked German aircraft manufacturing during Operation Argument, also known as "Big Week".

[8] On 8 April, the USAAF committed 664 bombers in an attack on Luftwaffe airfields in northwest Germany and aircraft manufacturing near Braunschweig.

[10] On 18 July 1944, Rüffler engaged in aerial combat with North American P-51 Mustang fighters west of Caen.

[14] Flying with JG 51 during the final days of the war, Rüffler claimed 25 further aerial victories on the Eastern Front.

[15] Following World War II, Rüffler joined the German Air Force, at the time referred to as the Bundesluftwaffe of the Bundeswehr.

In 1963/64, he flew Sikorsky H-34 helicopters for German VIPs, such us Helmut Schmidt and Kai-Uwe von Hassel.