Thread by @TrentTelenko

I've done threads on the S-200/5V28 in the ground to ground role previously, but I've yet to do so for the recent Kerch Bridge strike.

This🧵will change that.

1st - Black smoke is consistent with a 5V28 due to the combustion of the
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https://twitter.com/TrentTelenko/status/1686514588399845376

...remaining AK-27P/TG-02 propellants. So we are looking at four 5V28 Kerch missile impacts.

These hypergolic propellants let a late model 5V28 missile engage a SR-71 Blackbird traveling at Mach 3 at a range of 345 km with a 5 minute time of flight.

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censor.net/en/photo_news/…

And we ARE NOT seeing any black clouds in the air indicating a successful Russian SAM engagement of a 5V28.

No black smoke in the sky = No Russian SAM hits on a 5V28 missile.

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https://twitter.com/Liveuamap/status/1690310780623667200

At least two 5V28 missiles hit the Kerch Bridge such that both the road and rail bridges are now closed, plus most maritime traffic is now stacking up south of the Kerch bridge.

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https://twitter.com/BlueYelowBlue/status/1692616030034497740

There are reasons for this starting with the fact the 7 ton 5V28 missile has a 217 kg (478 lb) spherical ball bearing jacket warhead as standard equipment.

The important thing here is the 5V28 was ACCURATE.

Accurate enough to hit a 12 or 14 metre wide bridge span.

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Assuming the two assumed misses were due to inaccuracy, and the definition of circular error probability says 50% impacting inside a circle with a radius of the value of the CEP.

5V28 order of magnitude at Kerch value should be around CEP = 6-7 metres, or CEP = 19.7-23 ft.

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These are outstanding results for a modified 1980s long range SAM, whether equipped with either a home grown GPS/laser ring gyro (RLG) guidance package, or an digital scene mapping electro optic (EO) seeker that was repurposed from a Grom/Hrim and installed, isn't known.

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Given the open source data on GNSS jamming at the Kerch Bridge, Ukraine would have to make use of a controlled reception pattern antenna (CRPA).

CRPAs work by making use of the fact that the desired satellite signals,

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gpsworld.com/anti-jam-techn…

...& the jamming signals arrive from different directions.

In other words, a CRPA removes signals that arrive from particular directions (ground), whilst letting through signals from other directions (the sky).

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This is the best Ukrainian language youtube video on the Grom-2/Hrim-2 seekers that Google could find for me:

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And this is the best written, Ukrainian language, article on the Grom-2/Hrim-2 seekers from the same Google search:

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mil.in.ua/uk/%D1%80%D0%B…

The 5V28 main engine is throttled down for cruise once the missile has climbed to its intended altitude.

Exactly how much propellant is left in the tanks on impact depends on distance / ToF and what cruise thrust setting was programmed into the autopilot.

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Theoretically, a S-400 battery can probably bag a 5V28, as could an S-300PM2 or S-350 if the engagement geometry is right.

This did not happen.

As the S-300P/V/S-400 SAMs were ineffective.
Ukraine had to do something to fox them.

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So the Ukrainian had either some sort of ejectable decoys like the Iskander, or onboard jammers. [Note that the Soviets put X-band jammers into most of their supersonic naval ASCMs]

The only other alternative is mind boggling missileer incompetence🤷‍♂️

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https://twitter.com/TheDeadDistrict/status/1602244087901552640

As for the 5V28 weapon effects, the Kerch Bridge structure had to absorb the momentum of the impacting 5V28 at some velocity between 2-3 Mach, releasing its KE into about 1 square meter of bridge surface, followed tens of milliseconds later the overpressure pulse of the

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...warhead and then followed by the heat pulse of the combusting AK27P/TG02 propellants.

The 5V28 air vehicle mass, once the SRBs are dropped, with full internal fuel is ~3,900 kg i.e. just under 4 tons, of which ~2,186 kg is liquid propellant in the main tanks.

The 5V28 missile turbogenerator has a separate fuel supply using the same propellants to run missile systems for 5 minutes.

So the mass of the unfueled air vehicle, including 217 kg W/H, will be around ~1,770 kg.

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Based on a reasonable range estimate, the remaining 5V28 fuel on impact will be maybe 10-20% of total fuel load at Kerch Bridge impact.

Using the 10% fuel load number, we are looking at a 5V28 impact mass of ~1989 kg.

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Picking Mach 2.5 or ~830 m/s as the median impact velocity, that works out to be 685 megajoules of kinetic energy.

For reference, a 120mm tank gun delivers 12-13 MJ of kinetic energy at the muzzle.

While the 16 inch gun on the USS Iowa delivered 301 M/J at the muzzle.

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And then the weapons effects get much worse, not due to the 217 kg warhead, but because of the propellent.

The two component AK-27I/TG-02 hypergolic fuel is toxic, carcinogenic, corrosive,   inflammable and dissolves concrete by making it take in H2O.

19/ausairpower.net/APA-S-200VE-Ve…

Somewhere between 29 to 58.6 kg of Triethanolamine (TEA) is going to be blasted into the well fractured concrete & steel Kerch bridge structure by the 5V28's 685 M/J impact and 200 kg of explosive payload.


20/ sciencedirect.com/science/articl…

While some of the TEA will evaporate relatively quickly.

That which is in the impact/explosion zone is going to deeply contaminate the impact induced fractures going deep into the Kerch Bridge structure.

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Russia's Kerch Bridge is chemically contaminated with a hypergolic propellent that is now destroying its structural integrity.

And there is nothing Russia can do to stop it.

22/22 End