The Kh-22 [AS-4 Kitchen] is a supersonic air-launched cruise missile originally developed as an anti-shipping missile. First entering service in 1962, it is the oldest standoff munition in 🇷🇺 inventory. Production is estimated to have ceased around 1988. 2/13
The Kh-22 is carried exclusively by 🇷🇺 Tu-22M3 [Backfire-C] strategic bombers. The Tu-22M3 can carry up to 3 Kh-22s, though it is common for them to carry one or two at a time. 3/13
The most interesting and relevant technical aspect of the Kh-22 is its propulsion system. Unlike other cruise missiles that typically use jet engines, the Kh-22 uses an actual liquid-propellant rocket engine. 4/13
The Kh-22 is powered by a single R-201-300 engine developed by the Isayev Design Bureau (OKB-2). The R-201-300 uses TG-02 (also known as Tonka or Tonka-250) as the fuel and AK-27I, a formulation of inhibited red-fuming nitric acid (IRFNA), as the oxidizer. 5/13
TG-02 is a ~50/50 mixture of triethylamine and various isomers of xylidine. AK27I consists of ~73% nitric acid, ~27% dinitrogen tetroxide (NTO), and an iodine-based inhibitor. The inhibitor is present to prevent the nitric acid from rapidly corroding the oxidizer tanks. 6/13
The combination of TG-02 and AK27I is hypergolic, meaning they ignite immediately upon contact with each other in the absence of an ignition source. While this simplifies engine design by not requiring a separate ignition system, it complicates propellant handling. 7/13
The Kh-22's propellants, combined with the age of the missiles, themselves likely goes a long way to explain these in-flight failures. The newest units are almost 35 years old. The R-201-300 is a maze of pumps and propellant lines that have valves, seals, etc. 8/13
A single eroded seal could lead to a propellant leak that would easily cause an explosive engine failure, esp. since the propellants are hypergolic. For example, the Cygnus Orb-3 mission failed when one of Antares' 35-year-old NK-33 engines exploded shortly after launch. 9/13
Deviations in propellant composition due to improper storage could likewise cause a violent engine failure. For example, the nitric acid in IRFNA decomposes over time to nitrogen dioxide, water, and oxygen with exposure to light or elevated temperatures. 10/13
Despite the presence of an inhibitor, IRFNA will still slowly corrode its storage tank. Over time, this will leech material from the tank walls and contaminate the propellant. Either of these effects could produce a significant deviation in propellant composition. 11/13
These deviations could easily produce temperatures or pressures that exceed design parameters or potentially cause unexpected combustion instabilities leading to violent vibrations capable of tearing the engine and missile apart. 12/13
These are just a few examples of the innumerable failure modes that are possible when working with aged (and likely improperly stored/maintained) liquid rocket engines and propellants (that are also hypergolic). 13/13
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This is very interesting. AFAIK, the Kh-55SM, like the original Kh-55, was only designed to deliver a nuclear warhead and no conventional warhead was designed. These images indicate that this missile was fitted with an inert warhead. 1/4
This is another example of what was observed with the previous Kh-55 wreckage. 🇷🇺 is likely using these inert munitions as makeshift decoys to saturate and distract 🇺🇦 air defenses with the aim of enhancing the efficacy of their massed standoff strikes. 2/4
It remains unclear if these decoy munitions have been modified in any other ways to improve their performance as decoys. The most logical modification would be the inclusion of an electronic countermeasures (ECM) package. Thus, the contents of future wreckage bear watching. 3/4
Missiles of Ukraine I - Sapsan
OTRK (Operational-Tactical Missile System) "Sapsan" [peregrine in 🇺🇦] is a prospective single-stage, solid-fuel, short-range ballistic missile system. It has been under development in various forms since the mid-90s under a variety of names. 1/46
For clarity, Sapsan currently refers to the domestic variant, while "Hrim-2" ["thunder" in 🇺🇦] refers to the reduced range (MCTR compliant) export version. It’s also been referred to as "Grom" ["thunder" in 🇷🇺] or "Grim," a corruption of Hrim. 2/46
There is a profound asymmetry between 🇷🇺’s ability to strike targets in 🇺🇦 and 🇺🇦’s ability to strike targets in occupied 🇺🇦 territory and 🇷🇺. This asymmetry is a grave threat to both 🇺🇦’s war effort and its people that must be urgently addressed. 3/46
A) No numbers are provided for Iskander-K (9M728/9M729 [SS-C-7/SS-C-8]) ground-launched cruise missiles (GLCMs), the Kh-59 [AS-13 Kingbolt/AS-18 Kazoo] air-to-surface missiles, or the Tochka-U [SS-21 Scarab-B] ballistic missiles (BMs).
1/15
B) 🇷🇺 is averaging production of 26-28 units of cruise missiles per month (50/50 Kh-101 [AS-23 Kodiak] and 3M-14T/K Kalibr [SS-N-30A])
C) 🇷🇺 is averaging production of ~5 units of Iskander-M [SS-26 Stone] BMs per month. This is consistent with other independent estimates.
2/15
A brief 🧵 on the Kerch Bridge strike as much has been speculated on the method of the strike.
1/7) There are two real possibilities: a vehicle-borne IED (VBIED) or a tactical ballistic missile (TBM). Most seem to have concluded it was a VBIED and totally dismissed a TBM
2/7) This conclusion is extremely problematic. First, it is certain that 🇺🇦 possess TBMs with a range of at least 300 km (either ATACMS or Sapsan/Hrim-2) as demonstrated by the Saky airfield strike. I challenge anyone to explain the need to use a VBIED when 🇺🇦 has TBMs
3/7) Second, please explain how a moving VBIED would be remotely tracked at night and detonated. Cell/satphone service in the area is not guaranteed on top of any 🇷🇺 electronic warfare. Not to mention having to assemble a 2-5,000 kg bomb in 🇷🇺 and get it past inspection
There have been multiple reports circulating over the past 72 hours that 🇺🇦 forces have captured a 🇷🇺 general disguised as a lieutenant colonel. These claims are based on a recent video of some new 🇷🇺 POWs. Unfortunately, this seems to be false as I will detail in this 🧵1/5
A number of usually highly credible sources have claimed that this POW is in fact Lieutenant General Andrei Sychevoi, commanding officer of the "Western Grouping" of 🇷🇺 forces and 🇷🇺 units operating in Kharkiv. At a glance, there does seem to be some similarity between them 2/5
However, closer inspection reveals that they are two different individuals. This image of Sychevoi was provided by @CITeam_en and is dated from mid-June. Unless Sychevoi received a bad hair transplant between June and September, this POW cannot be Sychevoi 3/5
It is beyond belief for @amnesty to accuse Ukraine, a nation defending its sovereignty, democracy, language, culture, way of life, and people from a genocidal war of aggression waged by Russia, of endangering its citizens by fighting to defend its own population centers
The Ukrainian Government has undertaken massive efforts to evacuate civilians from areas near the frontlines. Kharkiv, UA’s second largest city with nearly 1.5 mil people has evacuated more than half its population. Pres. Zelenskyy recently issued additional evacuation orders…
…for the entirety of Donetsk Oblast. It’s unfortunately inevitable that some UA citizens will remain behind despite these orders as UA does not force its citizens to leave their homes if they are unwilling. Moreover, whether or not the UA Armed Forces operate in proximity…