Soviet nuclear test, RDS-5 near-ground burst at Semipalatinsk (1954)

This explosion is shown in a 50s soviet film simply called Ядерный полигон (links below), were it is portrayed as an airdrop test (that film ends in showing the hydrogen bombs tests from 1955, so this one could be from 1954 or 1955). There are also footages of this explosion shown in german documentaries by Phoenix (Nowaja Semlja - Der Archipel der Angst, Die Rote Bombe) were it is shown together with scenes of 1954 - 1955 tests (some of these different than the shown in Ядерный полигон) and asociated with airdrop footages.

Supposing that this was ground or near ground explosion at STS in the 50s, and assuming it was at least 1 kt in yield, possibilities are:
- Test 12 (03/10/1954). 2 kt, 130 m. RDS-4M test, airdrop [compare it to US test Teapot Post or UK test Buffalo R3 Kite] (see links below)
- Test 13 (05/10/1954). 4 kt, 0 m. RDS-4M test, possibly airdrop (see ref)
- Test 17 (26/10/1954). 2.8 kt, 110 m. RDS-5 test, airdrop [compare it to US test Teapot Post and UK test Buffalo R3 Kite]
- Test 18 (30/10/1954). 10-12 kt, 55 m. RDS-5 test, airdrop [compare it to UK test Buffalo R1 and Totem T1, or various US tests in the Operation Teapot]
- Test 19 (29/07/1955). 1.3 kt, 2.5 m. RDS-9 test, base [compare it to UK test Buffalo R2 Marcoo and US test Jangle Sugar]
- Test 20 (02/08/1955). 12 kt, 2.5 m. RDS-9 test, base [compare it to UK test Buffalo R1 and Totem T1] (see links below)
- Test 21 (05/08/1955). 1.2 kt, 1.5 m. RDS-9 test, base [compare it to UK test Buffalo R2 Marcoo and US test Jangle Sugar]

Another three possibilities are in 1956:
- Test 26 (16/04/1956). 14 kt, 0 m. RDS-41 test, base.
- Test 27 (25/04/1956). 5.5 kt, 1 m. Unknown device, base.
- Test 28 (24/08/1956). 28 kt, 90 m. RDS-4 test, tower. [compare it to various Teapot and Plumbbob tests. Also, see links]

The ID of the tests was suggested to be the test 18 in a now deleted video by @RadiationHazard , considering the source films suggest this was in 1954-1955 and noticing the duration of the incandescence of the fireball, that make unlikely it to be one of the lower yield explosions. It would make sense that it is portrayed often as an airdrop.

So presumably this could be the test nº18. The RDS-5 was an early tactical bomb that was first tested in a series of experiments in 1953. The program of 1954 started with a series of airdrop tests of RDS-4M charges, a smaller variant of the RDS-4 (first soviet tactical nuclear bomb) (tests nº10 to 13). Then, a series of experiments with different neutron initiators (implemented in RDS-3 and RDS-5 devices) was conducted (tests 14 to 18. The first, unsuccessful, test of the RDS-9 also took place in that period). Test nº16 was pivotal in that it was the first test of a device with a external pulsated neutron initiator and considered a very successful experiment. One source (see ref) mentions that the improved yield of test nº16 was rumored to be the result of higher plutonium mass and not from the new initiator, so Yuli Khariton ordered two tests of the RDS-5, one without the initiator (test nº17) and one with the initiator (test nº18). Test 18 was a second successful demonstration of the effectiveness of this new technology. Pressures reached the order of 1 billion atm and temperatures 1 million Celsius. VNIIEF reported a yield of 10 kt, while a source of the VNIIA mentions 12 kt (the percentage of the improved yield is not mentioned in the sources consulted and can't be assumed the device was exactly the same as the test 17 - different plutonium masses could been used). Important to note is that, if this was indeed the test 18, then the bombs dropping footage shown associated to this test in Ядерный полигон don't correspond to this explosion. The RDS-5 charges tested in 1953 and 1954 (six in total) were mounted inside the same ballistic casing of the RDS-2 and RDS-3 ("product 501-M") (see footages of the bomb dropped during the Totskoye exercises, that is a RDS-2 in such ballistic casing). The bombs shown in Ядерный полигон and some of the German documentaries that used these footages are RDS-4 or similar.
- Ref: https://pn64.livejournal.com/14939.html?noscroll#comments
Also http://militaryrussia.ru/blog/topic-788.html

- Ядерный полигон film: https://vkvideo.ru/video-14225254_162476901

- Video sources: https://www.youtube.com/watch?v=Fn5JaHpE5zU , excerpts of Ядерный полигон in much better quality.

Also, consider these videos:
- https://vkvideo.ru /video-14225254_162415840 (presumably test 19, 20 or 21, most likely nº20)
- https://www.youtube.com/watch?v=Dqf9WS6kKNk (presumably test nº12 or nº17)
- https://www.youtube.com/watch?v=osZ2dDxDajs (presumably test nº28)
- https://www.youtube.com/watch?v=8XPRkO75Hgw (presumably test nº28)
#nuclearweapons #sovietunion #ussr #coldwar #history #ядерноеоружие #СССР #история #tsarbomba

Видео Soviet nuclear test, RDS-5 near-ground burst at Semipalatinsk (1954) канала synthetic sunset