Helmut Kallmeyer, German chemist and soldier (d. 2006)
Helmut Kallmeyer (8 October 1910 in Hamburg – 27 September 2006) was a German chemist in the era of National Socialism. He served as a consultant in Adolf Hitler's Chancellery (Kanzlei des Führers) for gasification methods. Later, he worked in the Technical Institute for the Detection of Crime (Kriminaltechnisches Institut der Sicherheitspolizei, KTI). He was involved in Action T4, Nazi Germany's program to murder people with disabilities.