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Correct; the wavelength of SPY-1 is in the 7.5-15cm range.

This might be helpful to people. As I do recall the original SPY-1 was more F then E band, but the active array SPY-1E should be able to do all the lower wavelengths too. Bigger wont work so well given the limited antenna size.

Are we actually supposed to take seriously the sub-microradian radar beamwidth he claimed earlier?

I have no idea whether to believe it or not, because I've never tried to do the physics for a phased array radar set, and even if I had there'd be electrical engineering concerns I'd likely miss. But I trust Stuart enough to be willing to take his word for it.

Stuart derived those spot sizes from non-AEGIS radar systems (which, I presume, have nonclassified capabilities). Perhaps he could provide a reference that describes the parameters of such a system.

Simon_Jester wrote:Stuart derived those spot sizes from non-AEGIS radar systems (which, I presume, have nonclassified capabilities). Perhaps he could provide a reference that describes the parameters of such a system.

I'd love to see such a reference myself. It sounds completely preposterous to have a beamwidth smaller than the wavelength at a distance on the order of 100km.

It's possible that's not the literal beamwidth, but a composite one. In other words, given a series of phased array elements all converging on a space, there could be a very small region of interference where they add up to achieve peak intensity. The beams themselves might actually be wider.

Of course, one question that comes to mind is how quickly they can realign this array given that positioning accuracy must be very high in order to achieve this constructive interference with so many array elements. Rise time and settling time would be useful information, but of course, rather classified. The precision does seem absurdly high, especially if its repositioning time is quick, but then again, we are talking about a system on which the R&D costs alone probably run into the billions of dollars.

Just to put my two cents worth in: If (or rather, WHEN) we invade North Korea, I really do hope we go get the USS Pueblo back. After all, it still technically is on the active service list. It just doesn't seem right to leave a ship behind, amiright?

Omega Scythe wrote:Just to put my two cents worth in: If (or rather, WHEN) we invade North Korea, I really do hope we go get the USS Pueblo back. After all, it still technically is on the active service list. It just doesn't seem right to leave a ship behind, amiright?

Assuming that they don't blow it up before hand.

Seems that they did add another phased array when they did BMD upgrades. Basically, the HPD (High Powered Discriminator) is a small PAR with a narrow FOV, which is aimed via SPY-1 data.

Digging around the internet for a couple of minutes created this entry:

AN/SPY-2 High Power Discriminator (HPD) Radar: Later upgrades to support BMD will add SPY-2. It is a single face X-Band AESA radar based on THAAD hardware and software, and mechanically trained like Mk 99. After cueing from the SPY-1, it will perform long range discrimination against exo-atmospheric missile threats. Due to it's extreme power, detection and tracking of targets will be limited by the radar horizon only: 1,350 km for missiles with an apogee of 100 km, and 1,800 km for missiles that have an apogee of 180 km.

Stumbled across this while browsing the Internets, and I felt like I had to share. I hope it hasn't been posted before.

Darth Wong wrote:It's possible that's not the literal beamwidth, but a composite one. In other words, given a series of phased array elements all converging on a space, there could be a very small region of interference where they add up to achieve peak intensity. The beams themselves might actually be wider.

Of course, one question that comes to mind is how quickly they can realign this array given that positioning accuracy must be very high in order to achieve this constructive interference with so many array elements. Rise time and settling time would be useful information, but of course, rather classified. The precision does seem absurdly high, especially if its repositioning time is quick, but then again, we are talking about a system on which the R&D costs alone probably run into the billions of dollars.

For the first part, it's almost certainly the area of peak intensity, with an umbra of lower intensity around it.

The second, making the assumption that the AEGIS SPY-1 is more accurate that the little kid version they use at the airport, it is possible that they are as HIGHLY accurate as Stuart depicts. I don't know the operational details of the missile system, but there are very similar systems at the radar sites for airports, which they use for making detailed raster scans of weather systems using a pencil beam. Like everything else at the airport technical end, these are extremely good systems for accuracy (they have to be*).

(*my soon to be father-in-law is an engineer who works at Pittsburgh International on the radars. He and his coworkers are EXTREMELY anal human beings about data accuracy and regulation, since they've been conditioned to the notion that nothing less than perfect is good enough to keep our planes in the air. He even drives exactly at the speed limit at all times.)

NOAA has a SPY-1 loaned from the USN - I wonder if we could try and get any details on it that way.

Pelranius wrote:
Assuming that they don't blow it up before hand.

Highly doubt they would even bother; It's a ship from the 1960s. Apparently they use it as a museum ship in Pyongyang. I'd think they would have more important things to worry about.

On the note of the museum ships, why haven't we seen the USS Michigan? I love that ship; The guns are too awesome to behold. It's still mostly operable I think; I doubt it would take much refurbishing, considering the good shape the restorative society keeps it in. I certainly hope Stuart sees fit to bring that back.

Other possible ships are the USS Wisconsin (which was specifically ordered to not be modified in anyway that would impair a return to active duty) and The USS Intrepid (which is just sitting in New York). I love the idea of old ships coming back to active duty; It just feels that much more epic.

Omega Scythe wrote:On the note of the museum ships, why haven't we seen the USS Michigan? I love that ship; The guns are too awesome to behold. It's still mostly operable I think; I doubt it would take much refurbishing, considering the good shape the restorative society keeps it in. I certainly hope Stuart sees fit to bring that back.

Michigan? I don;t know of any Michigan that;s been preserved. The prow of one of the very odl Michigan's has been retained but the rest have gone. The current USS Michigan is an SSGN and she's definately around.

Other possible ships are the USS Wisconsin (which was specifically ordered to not be modified in anyway that would impair a return to active duty) and The USS Intrepid (which is just sitting in New York). I love the idea of old ships coming back to active duty; It just feels that much more epic.

The old Essex class CVs aren't recoverable, they're all in pretty bad shape (even Intrepid after her recent overhaul). I was on Yorktown last week and she's really rough, to be honest I'd be surprised if she's got more than another decade before she's too far gone to save. Midway might be recoverable. As for the BBs, the museum ships are mostly gone beyond the point of return to service. They've been modified to accept tourists and so on and that really limits their usefulness. For example, the bottom section of watertight hatches have been cut away to eliminate the step. Two of the four Iowas have had their guns demiilled (1/4 inch angle iron welded inside the breeches) so there's no point in bringing them back. I really don;t see that the other pair would be worth the effort, there's nothing they can do that other ships can't do better and cheaper. The navies aren't like air forces and armies, they need every aircraft and every tank they can get their hands on, the navies aren;t quite that desperate for ships.

Sorry for that slip; I meant the USS Missouri. Slip of the tongue, nothing more.

And I understand your explanations and accept them; you are the author after all, and the explanations do make sense. I just have a thing for refurbishing things from the past, ships especially. I DO have info, though, that says otherwise as to the fate of the Iowa-Class Battleships, more specifically to the Wisconsin (though it probably applies to the Missouri as well):

Congress has ordered that the following measures be implemented to ensure that, if need be, Wisconsin can be returned to active duty:

1. Wisconsin must not be altered in any way that would impair her military utility;
2. The battleship must be preserved in her present condition through the continued use of cathodic protection, dehumidification systems, and any other preservation methods as needed;
3. Spare parts and unique equipment such as the 16 in (410 mm) gun barrels and projectiles be preserved in adequate numbers to support Wisconsin, if reactivated;
4. The Navy must prepare plans for the rapid reactivation of Wisconsin should she be returned to the Navy in the event of a national emergency.

That's pretty compelling evidence, if you ask me.

And again, I would like to see the Pueblo rescued. I'll be damned if I see American hardware left in the hands of the North Koreans; This is one grudge we need to pay back.

Omega Scythe wrote:Sorry for that slip; I meant the USS Missouri. Slip of the tongue, nothing more.

Ah, right, That makes sense. Missouri is one of the pair that had her guns screwed over so she's pretty much written off. New Jersey is the other Iowa with damaged guns. Technically, Wisconsin and Iowa could be returned to service (the parts and plans have been prepared) but I honestly don't think they're worth the effort. They just require crews that are too large to justify their very limited utility.

Fair enough, but remember they're there; at the very least they could serve as shore emplacements and an extra bit of radar and such; using them in a limited way would probably cut down on the amount of crew they would need. Besides, you never know when you might need a few large caliber-shells put down, or a little extra support =P

You can just build new boats for half the trouble.

Stop raining on my parade =(

I am allowed my unreasonable dreams, and will continue to hold them as per my obstinate stubbornness =P

Stuart wrote: Ah, right, That makes sense. Missouri is one of the pair that had her guns screwed over so she's pretty much written off. New Jersey is the other Iowa with damaged guns. Technically, Wisconsin and Iowa could be returned to service (the parts and plans have been prepared) but I honestly don't think they're worth the effort. They just require crews that are too large to justify their very limited utility.

As an ex museum guy, you have no idea how right you are, and there is more to it than the physical condition of the ship.
Its more than just having the ship in good order (a problematic proposition for any museum, as money for preservation is gifted, not doled out by government as of right), its the people who know how to actually run and generally use the item to maximum efficiency, that is to say more than a day cruise around the local harbour, they must fight the ship and those skills atrophy over time if not used, and that the real elephant in the room.

Omega Scythe wrote:Fair enough, but remember they're there; at the very least they could serve as shore emplacements and an extra bit of radar and such; using them in a limited way would probably cut down on the amount of crew they would need. Besides, you never know when you might need a few large caliber-shells put down, or a little extra support =P

The problem is that the sheer cost of rerecommissioning those two ships is huge. The up-front costs are going to be staggering. The continuous cost of maintaining the crews (when those same crews could easily staff several modern warships with far greater total capability) is large. The cost of maintaining spare parts for an effectively unique class of two giant warships whose basic power plants and hull plan are seventy years old is... no. Just no.

Rerecommissioning a pair of Iowa-class battleships makes sense only in a very specific context: If you confidently expect to need massive amounts of naval gunfire support, if you plan to fight an extended ground campaign within effective gun range of the coast, if for some reason five-inch shells just will not suffice,... IF. There are a lot of ifs involved.

The sheer number of ifs is great enough that in a situation where every dollar spent reconditioning battleships is a dollar not spent on tanks or bombers or some other essential war need, the battleships are not likely to be reconditioned.

Simon_Jester wrote: The problem is that the sheer cost of rerecommissioning those two ships is huge. The up-front costs are going to be staggering. The continuous cost of maintaining the crews (when those same crews could easily staff several modern warships with far greater total capability) is large. The cost of maintaining spare parts for an effectively unique class of two giant warships whose basic power plants and hull plan are seventy years old is... no. Just no. Rerecommissioning a pair of Iowa-class battleships makes sense only in a very specific context: If you confidently expect to need massive amounts of naval gunfire support, if you plan to fight an extended ground campaign within effective gun range of the coast, if for some reason five-inch shells just will not suffice,... IF. There are a lot of ifs involved. The sheer number of ifs is great enough that in a situation where every dollar spent reconditioning battleships is a dollar not spent on tanks or bombers or some other essential war need, the battleships are not likely to be reconditioned.

That also applies now in our universe. The navy collectively wakes up screaming at the concept of the two remaining battleships being brought back into commission - in fact its been seriously suggested that Iowa be the subject of a Sinkex to make sure that political pressure doesn't force the navy to recommission her (obviously current legislation mkes that impossible - which is why it was passed). Personally I'd say that given today's circumstances, I can't imagine a worse disaster for teh navy than bringing the Iowa and Wisconsin back into service. In the context of The Salvation War, the ships are of even less use. The humans have unchallenged air superiority and enough aviation assets to make sure that any target that needs copious high explosive is better dealt with by air attack than a lumbering dinosaur. After all, this isn't the early days of the war when the humans were desperate for every tank and aircraft they could find. Now, the shortage is ammunition and somebody to fire it at.

Am I alone in thinking/feeling that using the USS Iowa as a target has a similar vibe to asking Richard Winters to be a tester for ballistic vests?

tim31 wrote:Am I alone in thinking/feeling that using the USS Iowa as a target has a similar vibe to asking Richard Winters to be a tester for ballistic vests?

Ships with equally illustrious battle records and a much greater role in the history of the US Navy have been sunk as targets before. It's an unfortunately common thing to do with obsolete warships, and arguably a more honorable fate than the alternatives of letting them rust into junk or cutting them up for scrap. After all, there's only so much demand for museum ships.