A while ago, we did an article on super maneuverable jet fighters. This clip does a better job of showing how they work then the ones we previously linked to. Notice how the individual exhaust ports on the jet engine move.
So the Navy has built a working rail gun….
Science got one step closer to science fiction Thursday morning, when the Navy used an electromagnetic railgun to fire a 7-pound slug at seven times the speed of sound.
The record-breaking shot, witnessed by a roomful of VIPs via remote camera at the Naval Surface Warfare Center, also moved the armed forces further down the road to a faster, safer, lighter, cheaper form of firepower.
So what are they going to use if for?
The Navy’s ultimate goal is a ship-mounted weapon capable of firing missiles 200 nautical miles in a six-minute arc into outer space and back to land, guided by GPS.
This dwarfs the range of the Navy’s current workhorse gun, the 5- inch MK 45, which shoots about 13 nautical miles.
The railgun uses electricity to propel its missiles, so they carry no fuel. The damage is caused purely by the kinetic energy of the missiles’ descent, which is projected to reach Mach 5, so they carry no warheads.
This means the missiles are cheaper. They are also smaller and safer, making them easier to store aboard ships and allowing for more variety in a vessel’s design.
For the Marines the gun would support, there are further benefits.
A ship carrying a rail gun would be able to begin bombarding the shore much sooner, far beyond radar range. It also would be able to fire more quickly.
The gun has a projected accuracy of 5 meters, which would minimize risk to Marines on the ground as well as any collateral damage.
I am sure that this gun has some uses as a ground support weapon. But I think that navy is being willfully blind here. A rail gun will only be an incremental improvements on the navy’s ability to blast ground targets. But it could change naval warfare completely. Just how would you defend a carrier from a rail gun?
Cruise missiles you can shoot down. In theory you can also shoot down ballistic missiles. But how are you going to stop an accurate rail gun that can fire from outside of radar range from sinking your carrier?
Today I made some attempt at cleaning up, my constant struggle, and found a lot of clippings I had meant to comment on. It seems only fitting to start with the review I ripped out of The Economist (January 6th, 2007). The book under the microscope is called A Perfect Mess: The Hidden Benefits of Click Here to continue reading.
If you ask an engineer a pipe is vessel and a tube is a structure. The standard measure for a pipe (i.e, the size you use to spec it) is the inside diameter because it is a vessel for transporting gas or liquids. The standard measure for a tube is measured by outside diameter because it is used for structural support.
If you ask a plumber, a pipe is any thick walled tube that can be threaded. A tube is anything that carries gas or liquids and is too thin walled to be threaded. Most plastic pipe is not threaded. However it is thick walled and that is why it is called pipe (You can also get plastic tubing).
In general, a plumber use inside diameter as the standard measures for both pipes and tubing. But Black Iron (and other ferrous metal pipes) and plastic pipes nominal size is only an approximation of the inside diameter. What’s more, the inside diameter will vary by thickness of the pipe wall (which is indicated by the pipe schedule). So a schedule 40 pipe will have an inside diameter that is almost twice as big as a schedule as a schedule 120 pipe even though they are both the same nominal size. To make matters worse, from 14” the nominal size is based on outside diameter.
To make matters even more complicated, the standard measure for annealed copper refrigeration tubing (otherwise known as ACR tubing) is always outside diameter. But this stuff is used by HVAC technicians, not your average plumber.
I don’t understand I why we all can’t be more like engineers. Do we really need a bunch of different standard measures for pipes when they are all used for transporting gas or liquids?
Normally, this is something I would post over at the Ethereal Voice. But I don’t think many of the people who read the Voice would really appreciate it. So I figured I would put this on my personal blog instead.
I found this at Sippican Cottage. We must be similar is some way because I Click Here to continue reading.
We have not been keeping up on the news the last couple of days. Here are some things that you might have missed.
The first link comes from the Financial Times…..
The issue at stake revolves around so-called delinquency rates, the proportion of people who fall behind on their debt repayments. When American households have faced hard times in previous decades, they tended to default on unsecured loans such as credit cards and car loans first – and stopped paying their mortgage only as a last resort. However, in the last couple of years households have become delinquent on their mortgages much faster than trends in the wider economy might suggest. That is particularly true of the less creditworthy subprime borrowers. MoreÂÂover, consumers have stopped paying mortgages before they halt payments on their credit cards or automotive loans – turning the traditional delinquency pattern on its head. As a result, mortgage lenders have started to face losses at a much earlier stage than in the past.
“In the past, if a household in America experienced financial problems it tended to go delinquent on its credit cards, but kept on paying its mortgage,” says Malcolm Knight, head of the Bank for International Settlements, the central banks’ bank. “Now what seems to be happening is that people who have outstanding mortgages that are greater than the value of their home, or have negative amortisation mortgages, keep paying off their credit card balances but hand in the keys to their house … these reactions to financial stress are not taken into account in the credit scoring models that are used to value residential mortgage-backed securities.”
Anecdotal evidence that this was going on has been piling up for awhile. Now it seems that it may be showing up in broader statistical samples. If this snowballs, housing prices could really drop.
Related to the above is this story from Bloomberg….
Standard & Poor’s said it cut or may reduce ratings on $534 billion of subprime-mortgage securities and collateralized debt obligations, the most sweeping action in response to rising home-loan defaults.
The downgrades may extend bank losses to more than $265 billion and have a “ripple impact” on the broader financial markets, S&P said in a statement today. The securities represent $270.1 billion, or 47 percent, of subprime mortgage bonds rated between January 2006 and June 2007. The New York-based ratings company also said it may cut 572 CDOs valued at $263.9 billion.
The reductions may increase losses at European, Asian and U.S. regional banks, credit unions and government-sponsored enterprises such as Fannie Mae, Freddie Mac and the 12 Federal Home Loan Banks, S&P said. Many of those institutions haven’t written down their subprime holdings to reflect a drop in market values and these downgrades may force them to recognize losses, S&P said.
The rating agencies have been downgrading things for awhile now. But doing half a trillion dollars worth in one whack still makes people sit up and take notice.
It is kind of funny that S&P is saying that the rating cut will force banks to recognize losses. The name of the game seems to be avoid having to face up to the facts at all costs. This from Naked Capitalism…..
But it seems that duplicity, um, creativity of various sorts is not only being encouraged but actually endorsed. First we had the Federal Home Loan Banks making massive loans to subprime lenders, particularly Countrywide. Now we have the SEC permitting subprime lenders to engage in what can only be described as misleading accounting.
If a mortgage servicer modifies a loan in a mortgage trust, an off balance sheet entity, in ways not comtemplated by the trust’s charter, the trust dissolves and the loans go back to the lender. But even though loan mods are often the best of the bad choices available when dealing with underwater borrowers, if the servicer does mods in a way that violates the trust charter, that means the poor overstrapped subprime lender has to take more assets onto its already not-so-hot balance sheet.
Enter the SEC with a magic wand. You can have your off balance sheet treatment, meddle with it like it really isn’t off balance sheet, but still keep your preferred accounting treatment.