I think you need to get out a bit more Naveleye.:}

Implying that Aster missiles have rather long minimum range of engagement, and that Aster ought to be supplemented with a closer-in air defense missile.


Wikipedia claims minimum engagement for the Aster 15 as 1.7 miles which I make to be about 2.86 seconds from impact assuming Mach 3 @ SLS. It would appear that the Aster 15 is for closer in engagement while the 30 is for longer range. Presumably the two versions are optimised for their respective roles. I doubt there's much you could do with another system in that last window of opportunity.


Also just consider for a moment that these are not little fireworks, 4.2m tall is one hell of a lump to be throwing out with 3 seconds left on the clock!


Please explain the advantage of midcourse updates via data link over semiactive, provided that one’s system has multiple electronically steered antennae which can keep many targets “painted” simultaneously around 360 degrees az. and 180 degrees el. with mucho more kilowatts than transmitters in Aster missiles can emit. In addition, missiles used by brand AB can also get data link updates.


At last the much vaunted network enabled capability being used for something properly! I should imagine that the exact advantages of such updates would be liberally coated with a warm 'official secrets act' goo, were you even able to find someone to ask about it.


It seems to me that PAAMS/Aster's principal advantage is that it can be fitted to a smaller ship than Aegis/SPY.


Considering the UK MoD love of insisting everything is gold plated I should imagine that it's got some serious clout, but then who knows until it gets used in anger.


Assuming that the system doesn't have to be mounted in a floaty, boaty thing, it seems to me that we have a pretty useful close air defence system there. Why not deploy it at all important military bases (i.e. targets)? Oh, I forgot, defence spending cuts. The money is to be spent on a rapid reaction force (read carrier groups) that can poke its nose into any other country's business anywhere in the world. Why would we ever need to defend the United Kingdom?


Yes.. because we've spent no money at all on UK air defence, those Typhoons (of which will may well end up with more of than pilots!) are just there to look pretty..

Quote:

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The Aster missile computes the predicted intercept time according to the target and environmental data it receives during the launch sequence. From the missile flyout and up to the point at which the active RF seeker switches on, the missile is inertially guided, receiving periodic target position and environment updates from the Firing Control Unit via the up-link. …

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There is no reason why the guidance system couldn't have been designed to switch into RF seeker mode immediately after being launched.

Quote:

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Please explain the advantage of midcourse updates via data link over semiactive, provided that one’s system has multiple electronically steered antennae which can keep many targets “painted” simultaneously around 360 degrees az. and 180 degrees el. with mucho more kilowatts than transmitters in Aster missiles can emit. In addition, missiles used by brand AB can also get data link updates.

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Taking a guess, a course update could be 'flashed' to the missile in a fraction of a second which would minimize the possibility of any system finding and blocking the ship->missile channel.

Alternatively it could be that the comms method used is similar to mobile phone technology that uses time domain multiplexing - each missile gets a time slot for communication and the command and control system iterates through each time slot updating one missile at a time.

There are many reasons why the system could have been designed as it is, but judging from what little is in the public domain it is quite an impressive piece of kit.

Also, I assume you meant 90-degrees elevation, not 180-degrees.

… From the missile flyout and up to the point at which the active RF seeker switches on, the missile is inertially guided, receiving periodic target position and environment updates from the Firing Control Unit via the up-link. …

There is no reason why the guidance system couldn't have been designed to switch into RF seeker mode immediately after being launched.

Soemthing like this?

… A Jet Vane Control (JVC) unit allows the RIM-7P to be vertically launched. The JVC unit rotates the missile immediately after it has cleared a ship’s superstructure, cancels the missile’s initial upward velocity, and controls transition to the initial intercept path. Once the seeker is pointing toward a target, the JVC is jettisoned. …

That description of the Aster – miisle flyout and all – They’re not boasting about the minimum engagement range.

http://www.fas.org/man/dod-101/sys/missile/rim-7.htm

… Taking a guess, a course update could be 'flashed' to the missile in a fraction of a second which would minimize the possibility of any system finding and blocking the ship->missile channel. …

Yes, but wouldn’t it be nice if the radar transmitter(s) could also continually illuminate the targets for the missile seekers?

Also, I assume you meant 90-degrees elevation, not 180-degrees.

I don’t how Aegis actually does it, but if I had any say-so, I’d specify a 180 degree elevation scheme. Then if a track passed overhead, instead of “azimuth something, elevation 88, 89, 90.,-89, -88, -87 …, “ wouldn’t be clearer to have “…88, 89, 90, 91, 92, 93 …”? Or maybe not. A matter of taste.

But the way, does this Sampson radar provide complete coverage of the sky overhead? We'll assume it does. :0]

The Ticos always suffered from topweight problems so I wondered how the T45s got away with such a tall mast.

A minimum engagement of 1.7 miles might sound good until you consider that a 4 ton object travelling at mach 2.5 - 3 would probably take the ship out anyway, even without a warhead, assuming that the Aster hits. You want to be taking those beasties out as far away as possible...

Someone please tell me it doesnt just rely on missiles (even if it is a spangly good one) for it's CIWS? Please tell me there's something there that spits out DU at a high rate of knots....

Yes it has 2 Phalanx 1B systems port and starboard. I must say against a Mach 3 target taking evasive action, I would bet too much on them. One thing that is overlooked is that a T45 can manoeuvre itself into an optimal Chaff C and D pattern without compromising it weapons capability in any way. An AB always needs to have the availability and arcs of directors in mind.

I'm sure Chairman Brown would prefer it to be the ship's claypigeon team out on the deck with their twelve-bores...

The Spanish L100 is a pretty compact design. Smaller than a T45 ans still carries AEGIS. I think the Aussies made a mistake in choosing that design.

I wonder why they chose Phalanx instead of Goalkeeper? Topweight / Space / Deck penetration issues?

The only time Phalanx has ever been fired in anger against an incoming missile it managed to lock onto the Missouri and put a few dents in her armour plate. Gloucester took the kill with a Seadart.

In trials against a supersonic Vampire the Phalanx test rig and barge was destroyed despite getting a few rounds on target by the debris from the (much smaller than a Sunburn) missile. This was considered to be a successful test.....

Should imagine that won't be sufficiently egalitarian...

Maybe the RN could throw uckers pieces?

Without consulting Wiki or any other online source if a sunburn weights 4 mT then the most reliable way of ensuring target damage/destruction would be NOT to have any chemical explosives that could be detonated/disrupted by outgoing warheads/rounds but a great big heavy lump of extremely dense Mach3 metal....

Solid Shot
 

So, while 'great big' & 'heavy' may need a bit of refining to a numpty like myself, this sounds difficult to get to Mach 3 very quickly & accurately. ( I'm familiar with the breathtaking acceleration figures of rocket missiles )...

As this nasty pointy thing coming the other way sounds horrendous, I assume we're talking something substantial ( D.U. cricket / foot ball better than explosives ? ) even at M3, to deter it - or better still have the launch vehicle knobbled by the airborne early warning / fighter combination which will of course be in attendance...- Just like the CVS has now - , a situation which will persist for a long time methinks.

+ Without such top cover, is it me, or with it's mix of missiles, wouldn't one or two serious attacks, with decoys etc thrown in, soon empty the magazines if the poor T45 is doing everything for the entire Navy around it, as seems the plan ?

Ok, hat, coat...

Goalkeeper news
 

Check out this thread on a another Board which says that Phalanx 1B are the only CIWS that will be fitted from now on.
http://p073.ezboard.com/fwarships1di...cID=6122.topic

and as biggus states that they will be all reused & update versions (total upgrade was said to be about 16 max i.e 8 ships worth :bored: this is the whole fleet not only the T45's)

One wonders what it has going for it below the water line?

I seem to recall that submariners say there are only two types of vessel - submarines and targets. :E

As I understand it, nothing much than harsh banter.

There is "The Machine That Goes Ping!!", although as it was stuck on as an additional (and therefore minimised) cost, it is certainly NOT the most expensive machine in the hospital, sorry - ship!

Spinflight - the supersonic Vampire referred to wasn't a Talos was it? AIUI, the US supersonic targets were retired Talos SAMs until they ran out of them at which point they bought a whole raft of 3M80s off Ivan to use as targets. Either way, both those targets are pretty substantial.....

I personally would describe the F100 as "an exceptionally ugly bordering on child-frightening" compact design.........

Like the T42 sonar, the T45 sonar has what can be best described as "Oh ****!" range when it comes to submarines (i think the official term is 'limited capability'). It's really meant to help it avoid mines. It's a trade off between the the ships primary AAW mission, a residual ASW capacity (which hasn't stopped the French and Italians putting a half way decent sonar in their Horizon class frigates - cousins of the T45) and of course cost. It's primary organic ASW asset of course is it's helo.

Reckon you're right with the space/deck penetration issues...relatively speaking, you can plonk a Phalanx almost anywhere on deck it'll physically fit and have a clear view from. Goalkeeper is a much heavier system which requires significantly more under-deck space (its ammo is stored and loaded from below, whilst phalanx has a drum mounted on the gun itself).

Goalkeeper also costs a lot more :hmm:.....but seems to me the better solution, though if it just won't fit, then it just won't fit.....

Probably issues with topweight - they've had to make the ship awfully beamy to take that tall mast. Goalkeeper (30mm) is a much better, heavier, system, but as WolvoWill says, Phalanx (20mm) can be put virtually anywhere, you just need a power feed. Goalkeeper needs below deck space, water and power feeds etc. A lot more expensive too - only 2 of the 3 CVSs were ever fitted with Goalkeeper (which we got in exchange for some RR Gas Turbines from the Netherlands).