In the course of researching and writing my article debunking the myth that jews ‘invented’ the classic rocket equation; (1) I noticed that the jew who was falsely claimed as the originator of it - the Soviet engineer and wunderkind Yuri Kondratyuk – was also sometimes credited with having invented the idea of the gravity-assist or the gravity slingshot; where in essence an object – such as a rocket – uses the gravitational pull of solar objects such as plants or stars to massively gain in acceleration by in essence ‘slingshotting’ around them.
Now before we get into this I will once again note Kondratyuk was in fact only half-jewish (his father) while his mother was a Russian aristocrat of decidedly German origins and his birth name was actually Aleksandr Shargei. (2)
The basis for then claim that Kondratyuk invented the idea of the gravity-assist or the gravity slingshot harks back to Kondratyuk’s attempt to popularise his 1929 book ‘Conquest of Interplanetary Space’ in the Soviet Union that he sent to early Soviet rocketry theorist and expert Nikolai Rynin in 1932, but the bundle of which included another Kondratyuk manuscript titled ‘To Those Who will Read in Order to Build’ which included a very vague description of a gravity-assist scenario using a rocket. (3)
The manuscript although ‘officially’ dated by Kondratyuk to 1918-1919 was in fact substantially modified till he sent it to Rynin in 1932 and there is no way to really know when any of the passages Kondratyuk wrote were written other than that they were written in 1932 or earlier. (4)
In truth these may well just be Kondratyuk appending the ideas of others to his own since the Austrian engineer Guido von Pirquet – the secretary of the ‘Society of High-Altitude Exploration’ (aka the ‘Austrian Rocket Society’) had talked about the concept of gravity-assists/slingshotting in a series of articles in ‘Die Rakete’ between 1928 and 1929. (5)
Even before either von Pirquet or Kondratyuk – remember Kondratyuk’s claim is only ‘dated’ to 1918/1919 because he claims on no evidence to have written it then but we have no evidence of such before 1932 and even pro-Kondratyuk scholars point out it was substantially altered between 1919 to 1932 – (6) Friedrich Zander (alternatively Friedrich Tsander) – a Baltic German from Latvia – first talked about the possibility of gravity-assist/slingshotting in his 1925 paper ‘Flights to Other Planets—The Theory of Interplanetary Travel’. (7)
In other words: the first person to discuss (and thus ‘invent’) the concept of gravity-assist/gravity-slingshot in terms of rocketry and space travel was not the jew Yuri Kondratyuk but rather the German Friedrich Zander.
References
(1) On this please see my article: https://karlradl14.substack.com/p/jewish-invention-myths-the-classic
(2) https://scfh.ru/papers/zemnaya-proektsiya-zvezdnoy-sudby/
(3) Rodolfo Batista Negri, Antonio Fernando Bertachini de Almeida Prado, 2020, ‘A historical review of the theory of gravity‑assists in the pre‑spaceflight era’, Journal of the Brazilian Society of Mechanical Sciences and Engineering, Vol. 42, a. 406
(4) Idem.
(5) Idem.
(6) Idem.
(7) Idem.