Jacques Lachnitt was a French engineer, a civil aeronautical engineer and an engineer with the Société nationale industrielle aérospatiale (SNIAS). A professor at the Institut supérieur d'électronique de Paris and at the ESTACA aeronautics and automotive engineering school, he became one of France's leading technical popularisers of the post-war era. He wrote many volumes in the "Que sais-je?" series: L'aérodynamique (no. 752), La mécanique des fluides (no. 1054), Les hautes températures (no. 956), Le titane et ses applications, Les matériaux réfractaires (no. 2093) and L'analyse de la valeur, as well as L'astronautique (Éditions du Seuil), Les avions de combat français and L'aviation d'aujourd'hui (Larousse). He also contributed to the journal Forces aériennes françaises.