Switzerland took delivery of the first of its 115 Bf 109s in 1938 when ten Bf 109Ds were delivered.

After this, 80 109 E-3s were purchased which arrived from April 1939 until just before the German invasion of France in summer 1940. During the war, a further four 109s (two Fs and two Gs) were acquired by the Swiss Air Force through internment. The 109Es were supplemented by eight aircraft licence manufactured from spare parts by Doflug at Altenrhein, delivered in 1944.




















In April 1944, 12 further G-6s were acquired in exchange for the destruction of a highly secret Messerschmitt Bf 110G night fighter which made an emergency landing in Switzerland. The new 109Gs suffered from numerous manufacturing defects and after problematic service were withdrawn from use by May 1948. The 109Es continued in service until December 1949.

With the start of the Battle of France, Swiss fighters began intercepting and occasionally fighting German aircraft intruding Swiss airspace. On 10 May 1940, several Swiss Bf 109s engaged a German Dornier Do 17 near the border at B?tschwil; in the ensuing exchange of fire, the Dornier was hit and eventually forced to land near Altenrhein.

On 1 June, the Flugwaffe dispatched 12 Bf 109 E-1s to engage 36 unescorted German Heinkel He 111s of Kampfgeschwader 53 that were crossing Swiss airspace to attack the Lyon - Marseilles railway system. The Swiss Air force sustained its first casualty in the engagement when Sub Lieutenant Rudolf Rickenbacher was killed when the fuel tank of his Bf 109 exploded after being hit by the Heinkel's return fire. However, the Swiss "Emils" shot down six He 111s.

On 8 June, a C-35 observation aircraft, an antiquated biplane, was attacked over the Jura Mountains by two German Bf 110s; the pilot and observer were killed. Later on the same day, Swiss Captain Lindecker led about 15 Swiss Emils to intercept a formation of German He 111s escorted by II./Zerst?rergeschwader 1's Bf 110s. The engagement resulted in five Bf 110s being shot down (including the Staffelkapit?n Gerhard Kadow) for the loss of one Swiss Bf 109.

In the latter stages of the war, Swiss Messerschmitts were painted with red and white striped "neutrality markings" around the fuselage and main wings to avoid confusion with German 109s.