DD(x) wowee!!

[Guest]

Incidentally, if the US were so committed to stealth and the Soviets had such a trump card against stealth, why would they tolerate the publication of the the key to the trump?

[Werner]

Incidentally, if the US were so committed to stealth and the Soviets had such a trump card against stealth, why would they tolerate the publication of the the key to the trump?

The fact is, I have the papers the Soviets published, and we looked at using them to understand flow and standing waves in the appearance of fossil beds to determine locations bones may exist in a terrestrial deposit. There is no reason to disbelieve this.

[Guest]

What waves are you transmitting through the fossil beds? Acoustic or electromagnetic?

[Foeth]

were able to detect deeply submerged submarines using the internal waves generated by the submarine which were observable as coherent millimeter-sized changes of the surface patterns above the submarine.

I've hear similar claims but I don't believe any of it.

[Werner]

What waves are you transmitting through the fossil beds? Acoustic or electromagnetic?

We weren't that sophisticated. We were looking for other markers in the bedding which indicated standing waves and the other phenomena the Russians relied on in their research. In this case the depth of the wave was a temporal marker of disruption and not an instantaneous indication.

[Werner]

were able to detect deeply submerged submarines using the internal waves generated by the submarine which were observable as coherent millimeter-sized changes of the surface patterns above the submarine.

I've hear similar claims but I don't believe any of it.

The articles generated considerable interest among naval professionals, but you may also recall the low ebb the end of the USSR brought to the ASW "business". The publication coincided with the abolition of an ASW "desk" at the Pentagon and the abandonment of a number of ASW systems and programs as a part of "The Peace Dividend".

[Foeth]

The reason I don't believe is that is difficult to attain accuracry within 1mm (or at least with great care) in laboratories when you are measuring wave heights. You usually use electrodes (wetted surface proportional to conductivity hence wave height) or optical systems (triangulation).

And say you are able to do it (which you're not), how do you intend to find one if you know if it's somewhere within a hundred square miles? Scan the entire surface? Correlate that data for several hundred measurements? Considering the stochastic nature of the wave height elevation, filtering out a milimeter heigh wave sounds far-fetched.

[Werner]

A Laser interferometer is quite able to distinguish differences of 1/4 the wavelength of light. The model used is not so interested in the different distances between the various samples and the observer, but the distance between the samples. You are looking for a particular pattern to emerge out of the static, kind of like the old-fashion color-blindness tests, not for the needle in a haystack. Once the pattern is established, you know the submarine's position to within a few dozen meters at the time the sample was taken, and you know it's course and speed. Of course in the 1980s the computing power required and the telecommunications from the satellite made this an academic exercise, but now it could possibly be done in real time. Perhaps the abandonment of SOSUS in the 1990s means the USN in fact followed this methodology for ocean barrier tripwires and added the instruments to the constellation of Naval Observation Satellites.

Satellite Lasers and Radars have been measuring the pressure wells and hills on the ocean caused by atmospheric pressures for some time. There was quite a significant one off the SE coast of Australia recently. A simpler use was the Laser reflector left on the Moon which was used to measure the orbit of the Moon to within a few millimeters in the 1960s.

I hasten to add that the amount of data gathered, the gathering techniques and the algorithms needed to process the data are far more robust and abundantly more verifiable than the extremely crude approach to modeling climate, with massive assumptions and cryptic, secretive and proprietary algorithms upon which certain profiteering scientists and politicians have raised the alarm of impending doom. The techniques for sensing deeply submerged submarines from space has received more public scrutiny and peer review than the work of elite climatologists like Nasa's Hanson, who refuses flatly to allow peer review.

[Foeth]

Lasers reflect particularly bad on fluid interfaces. If fact, most of the time they do not reflect at all. They do reflect on the froth on waves, which is easily a few millimeters thick, adding noise to the signal. Add this this that you need to correct for atmospheric distortion which may be bad considering the weather pattern. I doubt this distortion is helpful in keeping the laser of a single spot and I guess it will shift position (you are trying to find wave elevations for waves several meters long, the moon is a tad larger). Second, such an interferometer is a point source and you cannot obtain any directional information. Spacial correlation from one point is not really helpful. You'd pretty much have to nail the position of the sub first before you know where to aim an array of these sensors and the chances of a random sub happening to pass your beam are slim. And say you do manage to get past all these difficulties, you still have to get a pattern that is well below to signal-to-noise ratio.

And still, even if everything worked perfectly, I still say it will be difficult if not impossible to get the pattern of a wave a few mm's heigh from your data.

[Werner]

Lasers reflect particularly bad on fluid interfaces. If fact, most of the time they do not reflect at all. They do reflect on the froth on waves, which is easily a few millimeters thick, adding noise to the signal. Add this this that you need to correct for atmospheric distortion which may be bad considering the weather pattern.

All your naysaying has been addressed by astronomers who use adaptive optics to obtain better resolution images from modest terrestrial satellites than can Hubble, far out in space.

I do not pretend to know the answers to your objections because I am not a technologist, and we used the models for an entirely different purpose. What I can say is that the objections you raise, while good in and of themselves, are areas that have been addressed by those in the field, and based on the use of Lasers and Radar for satellite mapping of ocean currents and other well-known activities, must have been addressed to some degree in the last two decades.

I can offer no insight into the these technologies, and anything I say along these lines is sheer conjecture, but I would say that there are projects in closely allied fields which have had to solve these problems for their own purposes. Therefore, it is reasonable to assume there is cross-pollination in the Oceanographic realm which would solve many of your objections.

[Foeth]

All your naysaying has been addressed by astronomers who use adaptive optics to obtain better resolution images from modest terrestrial satellites than can Hubble, far out in space.

I know that. My naysaying doesn't apply to individual techniques to find the moon or make a good picture of some location in space, but the compounded difficulties of scanning a very very very large surface with a highly stochastic nature at a very very very high spatial and temportal resolution which should be analyzed by a pretty powerful computer and a nifty alhorithm to find a signal that is well below the signal-to-noise ratio.

Article: http://news.bbc.co.uk/2/hi/science/nature/6922312.stm

The satellite's radar altimeter, Poseidon-3, is designed to measure the sea level height to within a few centimetres. It will do this from its orbit more than 1,300km above the Earth

Pretty impressive nonetheless!

Factsheet

[Guest]

Whether Poseidon's achievements are impressive from the view from ASW warfare depends on the size of the area it is averaging to achieve the so-called cm resolution of sea level.

If it is averaging the level of 50 sq km of ocean surface to an accuracy of cms, that accuracy is useless for submarine detection. On the other hand, if it can individually measure the level of every square meter of the ocean to an accuracy of cm, and do so fast enough so that the pattern itself does not distort out of all recognition between the time when one scans the first part of it to the last, then that's a different story.

[Guest]

It is reasonable to assume there is cross-pollination in the Oceanographic realm which would solve many of your objections.

Not really, at least not if the assumption is the cross pollination would bear fruit in such a time frame as to make it reasonable to allow the expectation of its maturation to dominate current naval R&D.

[Seasick]

The Soviet censors completely missed the value of the paper that the US used to build its first stealth technology. There was hell to pay at the Soviet academy of Sciences in Moscow. (The censors not the paper's author.)

The author, who was a dedicated communist, was quite dismayed at the application of his reasearch by the USA.

[Guest]

The Soviet censors completely missed the value of the paper that the US used to build its first stealth technology. There was hell to pay at the Soviet academy of Sciences in Moscow. (The censors not the paper's author.)

The author, who was a dedicated communist, was quite dismayed at the application of his reasearch by the USA.

Soviet Union completely missed the significance of Sputnik also until the uproar it generated in the west trickled back into the Soviet Union. The Russians had a spare ICBM research booster sitting around, and the head man of Soviet rocketry program thought it would be neat to put a satellite into orbit with it. So he had his machine shop whip up an airtight aluminum sphere holding a battery and a transmitter in something like a 2 weeks and launched it. The Soviet political hierarchy thought he was jerking off and was about to reprimend him wasting state resources. Then the uproar in the west tricked back and the Soviet leadership decided to credit themselves with visionary leadership instead.

[bb-56]

Wow, reading through all your posts is sad, I thought something that looked that cool would be good but these weapons would work fine on a Burke Class and be seaworthy to boot. and less expensive if damaged or lost in hostile water.
Question then, is the 6" turret on the DDx really a lot better than the 5" 62 caliber on the later FLT II Burkes?

[Werner]

Question then, is the 6" turret on the DDx really a lot better than the 5" 62 caliber on the later FLT II Burkes?

My understanding was the /62 descends from the 5-inch/54, while United designed the 15.5cm to use standard NATO rounds. In addition to benefiting the supply chain, the 15.5 will be able to take advantage of R&D on the other 15.5s.

The Navy really wanted the fully automatic FMC (now United) 20.3cm, but it was too costly.

[Guest]

Speaking of seaworthy Burkes, anyone see the report on their bows crumpling?

[Werner]

You mean this:

Report: DDG 51s heavily damaged by �bow slams�

Staff report
Posted : Monday Oct 15, 2007 18:50:02 EDT

Thirteen Arleigh Burke-class destroyers have suffered �significant� structural damage in rough seas because designers didn�t account for the effect of �bow slams� on the ships� hulls, Navy documents say � and fixing the problem could cost almost $63 million.

A Navy PowerPoint presentation, obtained by Navy Times, confirmed a report Thursday in the British defense publication Jane�s revealing the design problems in the Burke class.

Support beams and other structures inside the destroyers warp so much from the stress of withstanding high seas that they must be cut out and replaced, even in new ships � the destroyer Gridley, commissioned in February, already underwent repairs in September. The document listed the following ships as damaged: Arleigh Burke, Curtis Wilbur, Stout, Paul Hamilton, Stethem, Carney, Gonzalez, The Sullivans, Ross, McFaul, Higgins, Winston S. Churchill and Lassen.

�Damage ranges from local buckling of deck transverse beams and shell web frames and shell longitudinals resulting in several inches of permanent deformation,� said one slide in the presentation.

Internal structure warping is not uncommon among surface warships; the Navy�s cruisers and frigates have gone into shipyards for hull-stiffening repairs.

With each ship designed to serve for around 35 years, the Burkes are the Navy�s only destroyers in service. The first ship was commissioned in 1991, and shipyard Bath Iron Works of Bath, Maine, announced it has started work on the last, DDG 112, expected to join the fleet in 2011.

$63 million... isn't that what it cost to equip the B-2 with an aluminum and plastic reclining lawn chair so the crew could sleep in their 40+ hour missions?

[Guest]

$63 million... isn't that what it cost to equip the B-2 with an aluminum and plastic reclining lawn chair so the crew could sleep in their 40+ hour missions?

For $62 million I guaranty I can equip each and every B-2 with far superior padded fire proof and G-force proof lawn chairs! God damn no bid contracts!