Index Home About Blog
[on www.warships1.com, in response to a statement about
	 Russian supersonic anti-ship missiles]

Don't hold your breath. Statements like that are an absurd
over-simplification. The Russian anti-ship missiles represent one set of
technical solutions to penetrating anti-missile defenses. They are not
the only set of solutions to those requirements nor are they necessarily
the best.

The Russian attention to hypersonics had its costs. The missiles are big
and heavy. limiting the number that can be carried. Their high speed
causes severe airframe heating that prevents them using infra-red
guidance. It also commits them to a straight run-in course (or, at best,
gentle curves). They have a heat plume that a thermal sight can detect
while the missile is still kilometers over the horizon.

There are such things as adaptive and iterative guidance systems that can
be applied to subsonic missiles that simply cannot be used on the
hypersonics. Subsonics have much lower signatures so can be more
difficult to spot. They don't guzzle fuel like hypersonics so can deliver
equal punch in a much smaller airframe. And so it goes.

For your information; Russian-style hypersonics are known as "streakers",
Western style highly agile subsonics as "dancers". Both have their place
but their relative merits are still being evaluated with great passion.

What is startling is how few of their naval weapons the Russians have
actually sold. P-270 Moskit has gone to China and they have sold 96 Kh-35
Harpoonski to Algeria. Contrary to your repeated assertions, they have
not sold any of their naval weapons to the US. They have sold a small
number of M-31 target drones to the US via Boeing on the simple logic
that it was cheaper to buy the actual missile in question than to spend
money developing a simulator. M-31 is a version of Kh-31, a short-range
air-to-surface missile, roughly equivalent to Maverick.

As a point of factual accuracy, neither the US nor the UK nor any other
major western sea power has adopted or has any plans to adopt any Russian
designed weapons system.

As a point of factual accuracy, according to SIPRI, Russia is now the 5th
largest arms supplier in the world in terms of value of signed contracts
and its relative position is declining.

I would like to revise my first sentence. please do hold your breath
while waiting, you'll find the experience instructive

Stuart [Slade]


Streakers and dancers complicate intercept in two ways. If we take the
intercept window of a crude, basic anti-ship missile (subsonic,
straight-in) as a baseline there are two options. The first is to use the
Russian approach and get the missile to cross that intercept zone as
quickly as posisble. This means adopting the shortest path across it and
flying that path as fast as possible. Hence P-270. This is a perfectly
viable approach.

The second is to stretch the time the CIWS needs to destroy the missile
to the longest possible point. In effect, this (a) reduces the percentage
chance of the system killing the missile and (b)reduces the number of
inbound systems a single CIWS can engage. One way of doing this is to use
an iterative guidance system in the missile.  This works by giving the
missile a fine-cut radar receiver which picks up and localizes the
emissions from the CIWS fire control system. The missile knows its own
coure and speed, it now knows the position of the CIWS (and can work out
the course and speed of the target). The computer in the missile knows
the algorithms used by the closed loop tracking system in the CIWS to
correct the aim of the CIWS. it can therefore work out what the firing
correction applied by the CIWS will be and alter the missile's flight
path to be somewhere else. This system is a service reality.

A third method is to physically shrink the envelope. The outer edge of
the intercept window is set by the maximum range at which the inbound
missile can be spotted, the inner edge is the range at which wreckage
from the shot-down missile will still strike the target ship. We can push
the outer edge in by flying the missile lower, by making it more
difficult to spot and by reducing its emissions. We can pull the inner
edge outwards by making sure the shot-down wreckage travels faster.

Putting all this together means that existing streakers fulfill
rerquirement (a) very well at expense of (b). In terms of (c), the
significantly pull the inner edge back (from 1 km to around 2.5) but have
major sacrifices in the outer edge. Their level of airframe heating,
their heat plume, the altitude at which they fly, their active radar
emissions, all mean they can be detected well over the horizon.

On the other hand, dancers make major gains in (b) at cost of performance
in (a). They sacrifice the inner edge of the engagement zone but achieve
major gains in reducing the outer edge by being inconspicuous. Typically,
they come in with their radars off (homing on command or IR), they are
coated with RAM (which streakers can't use since it burns off), they have
little airfrme heating and only a limited plume.

In summary, streakers move fast but have a larger, more distant intercept
zone. dancers move more slowly and evasively and have a much smaller
intercept zone, closer to the target ship. Close your eyes and visualize
it, you'll see what I mean.

This leads to a curious point which comes back to the Soviet's lack of
systems analysis. They designed P-270 to exploit certain weaknesses in
the SPY-1 radar performance. This it does, but by looking at a single bit
of equipment in isolation, they neglected to evaluate the target system
as a whole. Had they done so, they'd have found they'd managed to push
the intercept envelope back into an area where AEGIS works very, very
well.  Once Standard SM-2 had been given an IR auxiliary homing system,
it was more than capable of shooting the P-270s out of the sky. Its
essential to think system-to-system NOT weapon-to-weapon.

On average a P-270 weighs about 4.5 times as much as a Harpoon. This
loads the odds in favor of Dancers - remember effectiveness is related to
squares of numbers.

Your comments about Yakhonts containers do not represent new technology
or anything particularly unusual - most western missiles have been
delivered that way since the late 1960s. We treat them as "wooden rounds"
- get them, slip them into the rails, hook them up, run a self-diagnostic
then adjust people's attitude with them.

Sadly, I can deny the Russians are achieving a lot of success; I say
sadly because I thought they were going to do a lot better than they
have. Their equipment has stirred up a lot of interest but relatively
little of that has translated into sales. Where it has, it is usually
because of a lack of any opposition. Malaya represents the only case
where Russian equipment has secured an order in the face of Western
competition.

Stuart 

Index Home About Blog