On 6 July 1938, whilst watching an air display, Knoke made his first flight, a fifteen-minute joy ride in an old transport aircraft and took the preliminary examination for entry into the Luftwaffe.

11 Flying Training Regiment Schonwald, near Berlin and in August 1940 attended Jagdfliegerschule 1 (Werneuchen) under instructor Flight Sergeant Kuhl, an experienced operational pilot who had already seen action in both the invasions of Poland and France.

Posted to II Gruppe under Hauptmann Erich Woitke, his comrades included the future aces Gerhard Barkhorn, Günther Rall and Walter Krupinski.

In February 1942, Knoke participated with 3./JG 1 in Operation Donnerkeil, the Channel Dash of the German battleships Scharnhorst and Gneisenau and heavy cruiser Prinz Eugen.

Knoke destroyed his first "heavy" on his 164th operation: Maisie, a B-24 Liberator of the 44th Bombardment Group, which he shot down over Zwischenahn on 26 February 1943 – two of the crew survived;[2] journalist Robert Post, who on the first and last mission of "The Writing 69th", was among those killed.

Oberleutnant Heinz Knoke and his friend, Leutnant Dieter Gerhardt (killed in action against B-24s on 18 March 1943), developed the idea of dropping aerial bombs as a means to break up the tight combat boxes, thereby compromising the defensively strong USAAF bomber formations and rendering individual aircraft more vulnerable.

On 22 March, Knoke successfully downed the B-17 Flying Fortress Liberty Bell, of the 91st Bombardment Group, with a 250 kg bomb, intercepting it on its return flight after attacking Wilhelmshaven.

The Luftwaffe soon curtailed this practice, however as the carriage of bombs severely affected high altitude performance of the Messerschmitt Bf 109G and made these aircraft vulnerable to any escorting fighters.

On 17 August 1943 while intercepting a raid on Regensburg he was again wounded, this time by shrapnel fragments, and his aircraft was damaged by bomber return fire.

On 27 September 1943, Knoke shot down a B-17, Elusive Elcy, of the 94th Bomb Group using Werfer-Granate 21 unguided rockets launched from modified mortar tubes.

Knoke was shot down on 29 April in action against the P-47 of Captain James Cannon of the 354th Fighter Group and was hospitalised until August 1944 with severe concussion and related injuries.

Upon returning to base, Knoke developed a high fever and what later turned out to be a dangerous brain hemorrhage; following this, he had a complete nervous breakdown, grounding him until the middle of August.

Operating over the Normandy front, Knoke claimed a P-47 over Rânes, southeast of Argentan on 14 August, (of the 358th Fighter Group, piloted by 2nd Lieutenant.

By the end of August 1944 III./ JG 1 had almost been wiped out in the air battles over the Western Front; Knoke was ordered to move the unit to Fels am Wagram, prior to its transfer back to Germany for reinforcement and re-equipment.

Given orders to then transfer III./JG 1 to Vienna, Hauptmann Knoke was seriously injured in the legs by a Partisan-planted land mine during a car journey near Prague on 9 October 1944.

Although the Supreme Court of the Federal Republic of Germany declared this party illegal in 1952, Knoke remained in politics as a member of the parish council of the Gemeinde Schortens (Gemeindeparlament) from April 1954.