Georg August Weltz was born in Ludwigshafen in 1889. He studied medicine at the universities of Jena, Kiel, Königsberg (now Kalingrad) and Munich. In 1913 he was awarded a PhD on the aetiology of fibroids on the abdominal wall. During the First World War he worked in the medical corps, eventually employed as assistant doctor. From 1919 to 1920 he was employed as assistant doctor in a surgical clinic in Munich and from 1921 to 1936 he was active as a radiologist. From 1937 Weltz was a member of the Nazi party. In August 1939 he was enlisted in the Luftwaffe as a medic.

From 1937 Weltz sat on the board of the German Radiologists Association. From 1936 he was a lecturer at the university of Munich and head of the institute for aviation medicine which, from 1941 became known as the Institut für Luftfahrtmedizin der Luftwaffe. In 1943 he was appointed special Professor for Röntgenphysiologie (X-Ray physiology) with an emphasis on aviation medicine. At the university of Munich he taught intermittently work, sport- und military physiology.

After the war he was tried at the Nuremberg Medical Trial for his involvement in severe chilling at altitude experiments. But was acquitted along with Siegfried Ruff and Hans-Wolfgang Romberg. At a later trial in Munich, 1959, proceedings were terminated due to lack of evidence.

In 1952 Weltz was appointed special Professor for Röntgenphysiologie at the university of Munich. He also ran his own radiology practice.

He died in 1963.