Encountering Supermarine Spitfires for the first time over Dunkirk, Clade was impressed saying that the British fighters were almost the Germans' equals.

[4] In March 1941, Clade was made an instructor attached to Jagdgeschwader 27 into which 1./JG 1 had been merged, and stayed with this fighter unit for essentially all his remaining wartime career.

[5][6] On 7 August 1942, he indirectly made a potentially decisive impact on the future course of the African campaign, although he was most likely unaware of the fact at the time.

'Jimmy' James, who was flying Lieutenant General William Gott, the newly appointed Commander of the British 8th Army, to a staff meeting in Cairo.

Clade's attack forced the transport to crash land and the subsequent strafing run by fellow JG 27 pilot Bernd Schneider killed Gott and most other British troops inside the wreckage on the ground.

[7][8][9][10][11][12] While still flying in Egypt, having been promoted to Leutnant, Clade recorded his 10th air claim on 5 July 1942 when he shot down an RAF Spitfire fighter near El-Daba.

In a subsequent airfield attack against Melsbroek, Clade said the AAA positions were not manned, and aircraft were bunched together or in lines, which made perfect targets.

[17][18] Another source states that 13 Wellingtons were destroyed, as were five Mosquitoes, four Auster and five Avro Ansons from the Tactical Air Forces 2nd Communications Squadron.

[21][22][23][24] Clade and his fellow Gruppenkommandeur Peter Werfft disbanded the remainder of their unit near Saalbach between 3 May and 8 May 1945 and became prisoners of war.

[11] Clade finished the war as with the rank of Hauptmann, and was credited with 27 victories, including two four-engine bombers.

Clade was himself shot down six times, including in aerial combat on 5 October 1943 (during a mission resulting in his 18th victory), on 26 November 1944 and on 25 February 1945 (immediately after his 27th and last air kill).

He applied to become a civilian pilot with the newly formed Lufthansa in 1956 but was turned down because he exceeded the age limit by two years.