heavy missile barbette/bay/etc

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F33D
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Re: heavy missile barbette/bay/etc

Postby F33D » Sat Aug 17, 2013 2:26 pm

coldwar wrote:I find that hard to believe in most respects.

Missiles being larger, allowing space for more sensor equipment then modern day missiles.

They aren't larger than long range missiles of today. Not by a large margin. Maybe you are thinking of Trav Torps
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Re: heavy missile barbette/bay/etc

Postby coldwar » Sat Aug 17, 2013 3:58 pm

I'm sorry, my mistake. I thought you implied they were.

In any case, still missiles today can track a target at such long ranges. So IMHO trav missiles would be able to as well.
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Re: heavy missile barbette/bay/etc

Postby F33D » Sat Aug 17, 2013 4:39 pm

coldwar wrote:I'm sorry, my mistake. I thought you implied they were.

In any case, still missiles today can track a target at such long ranges. So IMHO trav missiles would be able to as well.

Nope. The longest range (for carried missiles that are larger than Trav ones) is ~150 miles. I have no idea what missile you are thinking of that acquires and tracks at many, many thousands of miles.
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Re: heavy missile barbette/bay/etc

Postby phavoc » Sat Aug 17, 2013 7:40 pm

F33D wrote:Nope. The longest range (for carried missiles that are larger than Trav ones) is ~150 miles. I have no idea what missile you are thinking of that acquires and tracks at many, many thousands of miles.
What missiles are you referring to? There are many missiles today, carried or launched by other craft or by ground launchers, that have ranges in excess of 150 miles.

Tomahawk and AGM-86 have range in excess of 1,000km. DH-10 from China and KH-55 from Russia have roughly the same range. Drop the range down to less than 1,000km and more than 200km and you have nearly a dozen other countries fielding cruise missiles in that range band.

Now an Exocet has a range of less than 200km, the Harpoon's is less than that, though not terribly so. Was that the class of missile you were referring to?
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Re: heavy missile barbette/bay/etc

Postby coldwar » Sat Aug 17, 2013 9:10 pm

I've just had a couple thoughts I'd like to share.

The first one is are we assuming that a missile is constantly accelerating to its target. If you take a moment to see how many turns it takes for a missile to reach a target it looks like that it does appear missiles reach a maximum speed, then only using whats left of its fuel to correct its path. At some point.
Not so sure on this, but something worthy of thought.

The second, is why with a normal missile a good gunner roll helps, could possible be that the gunner is having to put in a distance in to the missiles computer of when it should start correcting courses when it has its best lock. To early, the missile could make to many corrections, to late it cannot correct enough to hit in the first place.
This one sounds fairly sound, and easily supports that a standard missile also needs to be pointed at the target upon being fired, which also would account a gunner using a skill check to maximize the chances of the missile hitting.

Otherwise, here is an after thought. Most missile ranges are based on fuel capacity, mass, drag and lift. Not its capability to see the target. (In space, drag is very unlikely so that can be ruled out, another can be removed too.)
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Re: heavy missile barbette/bay/etc

Postby SSWarlock » Sun Aug 18, 2013 10:21 pm

coldwar wrote:<snip> In space, drag is very unlikely so that can be ruled out, another can be removed too.
True, though "drag" of a sort could be considered a factor if a missile impinges on a strong-enough gravity well on its way to its target.

Hmm. That's gives me an idea for a new thread.
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Re: heavy missile barbette/bay/etc

Postby locarno24 » Mon Aug 19, 2013 7:43 am

What missiles are you referring to? There are many missiles today, carried or launched by other craft or by ground launchers, that have ranges in excess of 150 miles.

Tomahawk and AGM-86 have range in excess of 1,000km. DH-10 from China and KH-55 from Russia have roughly the same range. Drop the range down to less than 1,000km and more than 200km and you have nearly a dozen other countries fielding cruise missiles in that range band.

Now an Exocet has a range of less than 200km, the Harpoon's is less than that, though not terribly so. Was that the class of missile you were referring to?
Note that none of the missiles you refer to track from launcher to target - they fly on GPS or inertial to a waypoint (or along a series of waypoints) then 'fire up' sensors for terminal guidance. If they do so and there's nobody there (a failed gunner check) then they haven't a hope of acquiring a target.

Also note, however, that the main reason they do this is that these are all over-the-horizon weapons (or at least are capable of this, even if a lighter weapon like exocet is not always employed this way), and it's a physical impossiblilty for such a weapon to have a track on its target with a line-of-sight sensor.

In a space-to-space missile....this is less of an issue as there is no 'horizon'


To put into perspective, as I understand it, traveller missile ~ block X harpoon in size, traveller torpedo ~ tomahawk SLCM in size.
Understand that I'm not advocating violence.
I'm just saying that it's highly effective and I strongly recommend using it.
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Re: heavy missile barbette/bay/etc

Postby Solomani666 » Thu Aug 22, 2013 12:29 am

F33D wrote:The whole turret/barrette/movable mounts for missiles is a bit silly. Missiles are not like rail guns. They can maneuver on their own. They would more likely be set up similar to VLS's on modern warships. Also, all batteries would be considered to be "bearing" no matter the size/configuration of ship.



IMTU

I consider all missile turrets/barbettes/bays to be bearing.

Whether a missile or torpedo launcher is mounted in an actual rotating turret/barbette depends on the ship design.

Ships such a Dragon class SDB have their missile racks in small non rotating pop-open bays.
Exchanging these missile racks to another weapon type would require a major overhaul if even at all possible.

A torpedo barbette can be built into the ship as a 5 ton bay, or mounted as a standard barbette.
The advantage of mounting it in a standard barbette is that it allows the weapon to be changed to a different type without a major overhaul.


.
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Re: heavy missile barbette/bay/etc

Postby phavoc » Thu Aug 22, 2013 1:17 am

locarno24 wrote:Note that none of the missiles you refer to track from launcher to target - they fly on GPS or inertial to a waypoint (or along a series of waypoints) then 'fire up' sensors for terminal guidance. If they do so and there's nobody there (a failed gunner check) then they haven't a hope of acquiring a target.

Also note, however, that the main reason they do this is that these are all over-the-horizon weapons (or at least are capable of this, even if a lighter weapon like exocet is not always employed this way), and it's a physical impossiblilty for such a weapon to have a track on its target with a line-of-sight sensor.

In a space-to-space missile....this is less of an issue as there is no 'horizon'

To put into perspective, as I understand it, traveller missile ~ block X harpoon in size, traveller torpedo ~ tomahawk SLCM in size.
Tomahawks CAN use GPS, but it's not required. Depending on the version, they can utilize their internal sensors. TLAM's mount inertial and terrain contour matching (TERCOM) radar guidance. The TERCOM radar uses a stored map reference to compare with the actual terrain to determine the missile's position. If necessary, a course correction is then made to place the missile on course to the target. Terminal guidance in the target area is provided by the optical Digital Scene Matching Area Correlation (DSMAC) system, which compares a stored image of target with the actual target image (source - FAS website).

Exocet's don't use GPS, neither do missiles like the SS-N-22 Sunburn. In space they will need to either be command-guided, use onboard sensors, or a combination of both. Pretty much like today's missiles, except as you pointed out, there's no sex in the champagne room, err, I mean there's no horizon.

As to it being "impossible" for a weapon to track it's target on a line-of-site sensory, that's incorrect. Many nations have deployed weapons that pop-up on their target right before impact to get a final onboard sensor lock. Some of these will then engage secondary boosters to get to supersonic speeds to make it much more difficult to line of sight defenses to take them out. The Harpoon is just one of many missiles with this capability.
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locarno24
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Re: heavy missile barbette/bay/etc

Postby locarno24 » Thu Aug 22, 2013 2:02 pm

As to it being "impossible" for a weapon to track it's target on a line-of-site sensory, that's incorrect.
Sorry. Meant to specify "at the point of launch" - i.e. 100 miles or so downrange - it's impossible to have line of sight at the missile's cruising altitude; hence the inertial/gps/whatever guidance to get you to attack position.

However, that's due to the earth's curvature - which isn't an issue for space-to-space missiles
Understand that I'm not advocating violence.
I'm just saying that it's highly effective and I strongly recommend using it.
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Re: heavy missile barbette/bay/etc

Postby phavoc » Thu Aug 22, 2013 2:54 pm

locarno24 wrote:Sorry. Meant to specify "at the point of launch" - i.e. 100 miles or so downrange - it's impossible to have line of sight at the missile's cruising altitude; hence the inertial/gps/whatever guidance to get you to attack position.

However, that's due to the earth's curvature - which isn't an issue for space-to-space missiles
Yeah, if you are talking ships. But if you have aircraft-launched missiles it's possible. Though I would suspect the only targeting at that range would be via electronic emissions. While it's possible to get electro-optical sighting at that range, it's very uncommon.

The Russians do have a number of air-launched missiles that can be guided by the launch craft and then go into self-seeking mode when they reach the target. It used to be the chances of them getting that close (with an F-14 being able to target six of them simultaneously, at range even, with the Phoenix missile) was unlikely. Sadly the idea of fleet defense (and the cruise missile defending capabilities of the Phoenix) have fallen along the wayside.

What's Tom Cruise going to fly now? An F-18 just isn't the same... :cry:
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locarno24
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Re: heavy missile barbette/bay/etc

Postby locarno24 » Fri Aug 23, 2013 6:58 am

What's Tom Cruise going to fly now? An F-18 just isn't the same...
Something with an X-Box pad, given the amount of effort that's been going into navalised drone trials recently.
Understand that I'm not advocating violence.
I'm just saying that it's highly effective and I strongly recommend using it.

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