Helmut Mertens (also known as "Pitt") (11 November 1917 – 17 January 1984) was a German fighter ace of World War II.

His victory tally as a fighter pilot is reported as high as ninety-seven or as few as fifty-four aircraft confirmed shot down.

[citation needed] By the outbreak of war on 1 September 1939, Mertens had been commissioned as Leutnant and was a fighter pilot flying the Messerschmitt Bf 109 with I.

With this unit he participated in Operation Case Yellow during the Battle of France and on 19 May 1940, shot down a Royal Air Force Hurricane fighter his first combat victory.

His unit provided escort cover for German bombers attacking England and on 26 October 1940, he shot down another Hawker Hurricane fighter.

[5] Between 6 April 1942, and 26 July 1942, he shot down fifteen more Russian aircraft, primarily Lavochkin-Gorbunov-Gudkov LaGG-3 and Polikarpov I-153 fighters and Ilyushin DB-3 bombers, bringing his tally to forty confirmed victories.

[1] On 2 October, he was temporarily appointed Gruppenkommandeur (group commander) of I. Gruppe of JG 3, replacing Hauptmann Klaus Quaet-Faslem until 2 November 1942.

[8] Documentation concerning Mertens service in the next eight or nine months from the time of his award until July 1943 is scarce and no details of his actions as a fighter pilot are known.

[15] According to Obermaier, he was credited with about 750 combat missions and 54 confirmed air victories and the sinking of a Russian gun boat.