Moderators: Alyrium Denryle, Edi, K. A. Pital
...for the simple reason that infared light only travels about half a meter underwater, due to it's very short wavelength (about 800nm).Detecting subs with infrared systems simply doesn't work
Stuart Slade wrote: Lets have a look at how wake-homers work. Basically, they detect the difference between the wake and the water that surrounds it. To be more precise, they detect the boundary between the wake and the non-wake. At that point there are two different models used.
Wake-crossers proceed diagonally through the wake until they detect the boundary. Then they turn through 90 degrees and make another diagonal transit across the wake until they reach the opposite boundary. Then they repeat the turn, heading back through the wake etc etc. Obviously, this means they use a lot of distance to gain on the ship they are chasing.
Wake-nibblers proceed across the wake until they detect the boundary. They then cross the boundary before making the turn. They recross the wake boundary and turn again. So, instead of crossing the entire wake, they just cross and recross one boundary. There are a few different sensor systems used.
Sonar. The torpedo is equipped with a small, upward pointing sonar that detects turbulence in the water.
Laser. The torpedo is equipped with an upward pointing laser that measures the turbidity of the water
Thermal. The torpedo has a temperature sensor that detects the cooler water in the wake.
It should be noted that wake-homing torpedoes are not uncommon. The French have a wake-homing derivative of the F-17, the Italians one of their A-184 and the US a version of the NT-37F/G. The characteristics of wake-homers are pretty well understood; the idea that they are some sort of mysterious Russian super-weapon just ain't so.
Wake homers are an area attack weapon. The idea behind them is that a submarine doesn't have to close on an enemy formation in order to launch an attack; it can stand off and "brown" that formation with a salvo of wake-homers. The advantage here is that the target represented by the ship formation is that of the formation itself plus the length of their wakes. This makes a big target. In contrast, the acoustic homing used by other torpedoes means the eel has to get significantly closer before its in the acquisition area of its homing head. The problem with wake homers is that they have no discrimination; they follow the wake - there is no way they can determine what wake they are following.
A more serious problem is speed/range. Whether they are wake-crossers or wake-nibblers, the torpedo has to eat a fair amount of distance before it will contact the target. Worse, its in a tail chase. Under such circumstances, a normal torpedo has to have something like a 50 percent speed excess over the target to make a hit (in other words, to hit a 30 knot carrier in a tail chase, we have to use a 45 knot torpedo). Using a wake-homer, the margin is between 2 and 2.5 times (in other words to hit a 30 knot carrier with a wake-homer, the torpedo has to have a speed of between 60 and 75 knots). That's a serious torpedo. There's also a problem of range. The torpedo has to get into the wake and run up the wake at high speed and that eats range.
Of course, the good news is that if the wake-homer does hit, its going to blow the stern off the target.
There are a wide variety of defensive manoeuvers that can be used. One is simply to cross wakes - this creates an area of extreme turbulence and the torpedo goes around and around inside it until it ..... you get the idea. Spreading wakes either by divergence or manoeuver is also a good idea (the torpedo has to run further between wake boundaries). So is countermining - wake homers are VERY predictable in how they come in and, once detected, their course can be projected with great accuracy. The Belgians did some interesting experiments with the Bofors 375 mm rocket launchers on their Weilingens and countermined F-17 wake homers.
Of course the problem is detecting and localizing the threat. The Senior put his finger on the problem here; dataload. The data processing requirement of an ASW/torpedo defense engagement is (at best) equal to that of an AAW engagement. Most ships don't carry the kit.
The Russians found the same as NATO - 53 cm (21 inch) wake homers just don't work very well. They don't have the range/speed characteristics needed. Thats one reason why they went to the big 65 cm which is a lot more convincing. That worked a lot better. As has been hinted, there has been a lot of work done on countering wake homing weapons, most of which is highly classified. However, it is fair to say, if you want to sink a specific ship out of a formation, wake homing is not the weapon of choice.
One of the reasons Canada needs those subs was to patrol the North West Passage. It is Canadian territory but Russia, U.S. and Denmark are clamouring that it is really international territory and to prove it, a few years ago the Russians launched a cruise missile (or was it an ICBM?) in a test in the Arctic, the Americans constantly go through the Arctic with their subs and the Danes gone through there with a few of their ships (I don't think it was military). They do not recognize the Canadian sovereignty over the Arcitc even though Canada has claimed it for about a century.Stravo wrote:Why do the Canadians feel they need subs? They have their neighbor to the south to protect them from errant ice flows and polar bears right?
On a serious note I hope those sailors will be fine.
Well the Canadian Army regularly patrols the arctic with the Regular Force and the Rangers. Plus we have a station on Baffin Island. I think our sovereignity over the arctic is well established. Although it doesn't hurt to patrol it with subs too. But given the performance of the "new" subs lately, I think it will be several years before they are doing arctic patrols.Enigma wrote:Stravo wrote: One of the reasons Canada needs those subs was to patrol the North West Passage. It is Canadian territory but Russia, U.S. and Denmark are clamouring that it is really international territory and to prove it, a few years ago the Russians launched a cruise missile (or was it an ICBM?) in a test in the Arctic, the Americans constantly go through the Arctic with their subs and the Danes gone through there with a few of their ships (I don't think it was military). They do not recognize the Canadian sovereignty over the Arcitc even though Canada has claimed it for about a century.
Want to guess the reason why those nations want that land? Because if they can successfully prove it is international territory then the Americans have a shortcut for their oil from Alaska, 40% of Canada's untapped oil reserves, 48% of untapped natural gas reserves are in the Arctic. I heard that there is enough oil there to supply the current needs for about 300 years. Whether that is bullshit or not I do not know.
They've also had the Nautilus and first Soviet ICBM launches there.Cpl Kendall wrote:The Soviet Typhoon class SSBN was designed with that in mind. It would hide under pack ice, then surface to launch her missiles.Admiral Valdemar wrote:Good site for hiding boomers too I would imagine.
Apology accepted. But what can we expect. They sat in mothballs for ten years. And the Liberal Canadian government is notorious for spending the bare minimum on our military. It looked to them like a good deal. I can't believe the Navy went along with it.Pulse wrote:http://news.bbc.co.uk/1/hi/scotland/3719760.stm
Oh dear. On behalf on my fellow Brits I would like to apologise for selling Canada such piece of shit.
To paraphrase from Star Trek: Perhaps [the Brits]should offer them a refund.LONDON, England (AP) -- A Canadian navy submarine obtained secondhand from Britain just four days ago was drifting in the Atlantic on Wednesday as British ships battled through rough weather to reach it and tow it ashore.
Three crew members were airlifted to Ireland for treatment of injuries sustained in the fire that damaged their vessel, and one was in critical condition, Britain's Ministry of Defense and the hospital said.
The ministry said a helicopter had intended to take the injured men to a hospital in Londonderry, Northern Ireland, but had to divert on short notice to Sligo, in the Republic of Ireland, because one of the crew members needed immediate treatment.
"The condition of one of the men deteriorated and gave us cause for concern," a ministry spokesman said on customary condition of anonymity. "The helicopter landed as quickly as it could."
Sligo General Hospital said the man was in critical condition and his two shipmates had been able to walk in. It gave no further details.
HMCS Chicoutimi, on its maiden voyage as a Canadian vessel, sent out a distress call Tuesday after a major electrical fire broke out on board. Britain's Royal Air Force sent a search-and-rescue helicopter to the sub, some 100 nautical miles (185 kilometers) northwest of Ireland.
Three British naval vessels and two tug boats planned to tow the sub to a Scottish naval base, but a Canadian naval officer said an attempt to get a tow line to the vessel might not happen before Friday because of the bad weather.
The lead rescue ship, frigate HMS Montrose, reached the Chicoutimi at about 1 p.m. (1200GMT) on Wednesday, and pulled alongside to drop off medical staff and supplies and assess the damage, the Ministry of Defense said in London.
Canadian officials had said earlier that nine crew members who suffered minor smoke inhalation were tended to on board by a British doctor. No injuries were reported among the other 48 crew members on the submarine, which is drifting after its engines were shut down as a safety precaution.
"Well, they've got emergency lighting on board. It is probably going to get a little bit cold, but they have sufficient blankets and other means to keep warm on board the submarine," said Commodore Tyrone Pile, commander of the Canadian Atlantic Fleet. "It's going to be uncomfortable with the movement of the sea."
Lieutenant Commander Denise Laviolette of the Canadian navy said the vessel might not be towed to shore before the end of the week.
"Because of the weather conditions out there -- we still have six to eight meter (20 to 26 foot) waves and 35 knot (65 kilometer per hour) winds, so it's still pretty much a gale -- there might not be a window of opportunity until Friday to try to get a tow line to her," Laviolette said.
An Irish naval vessel, LE Roisin, tried to reach the sub Wednesday but turned back after being damaged in heavy seas, the Irish Defense Forces said.
Another British ship laden with food and fuel and carrying a medical team and helicopter was also on the way.
Laviolette said the submarine would likely be towed back to the Clyde naval base in Scotland.
Pile said the blaze was worse than commanders first thought.
"This was a major fire," he said, adding that it damaged the commanding officer's cabin and an electrical equipment room on a separate deck.
A second separate small fire broke out in an oxygen generator, but it was quickly smothered, he said.
Officials initially described the fire on Tuesday as small and easily extinguished.
The incident has highlighted concerns about four secondhand subs Canada recently purchased from Britain.
A deal for the four Victoria-class submarines was agreed in 1998, but the handover experienced lengthy delays amid escalating costs and technical problems. Critics say the subs have a checkered history, cost too much and were not in good shape.
The submarines were originally built in the late 1980s and early 1990s for the British navy. They were mothballed in 1994 when Britain decided to stick with an all-nuclear submarine force.
The Chicoutimi, a diesel-powered patrolling submarine formerly called HMS Upholder, was only turned over to the Canadian navy on Saturday and was on its way from Britain to the Canadian port of Halifax.
It is the last of the subs to be delivered to Canada, but making them operational has been delayed by the need to repair cracks found in key valves after the vessels were brought out of storage.
The Times newspaper reported last week that the four submarines had been "dogged by serious malfunctions and corrosion."
BAE Systems, which was given the contract to prepare the submarines for the Canadian Navy, declined to comment on the report.
Yep, for the money that's been shelled out on the Upholders so far, we could have bought two brand new German Type 212 boats, which are a new design that come with all the goodies of a modern diesel boat, including AIP drive...Cpl Kendall wrote:Considering that we could have bought new from the Germans, Dutch or Russians I think we should get a refund.
We've spent close to $1 billion on the Upholders so far, but that's probably in Canadian dollars, not USD.I don't know how much money has been spent fixing them up, but I do know that the original lease price was around a quarter million pounds (with the sale at the end of the lease being for just one pound). A U212 goes for about 400 million dollars, so the original amount of money outlaid wouldn't have been bought one.
That's all nice and dandy but how does that stop American subs from leisurely pass through the NW Passage? Are the Rangers going to dive into the icy cold water and knock on the hatch and asked them nicely to leave? "Uhm excuse me captain, but if you leave we'll give you some whale blubber, eh?"Cpl Kendall wrote:Well the Canadian Army regularly patrols the arctic with the Regular Force and the Rangers. Plus we have a station on Baffin Island. I think our sovereignity over the arctic is well established. Although it doesn't hurt to patrol it with subs too. But given the performance of the "new" subs lately, I think it will be several years before they are doing arctic patrols.Enigma wrote:Want to guess the reason why those nations want that land? Because if they can successfully prove it is international territory then the Americans have a shortcut for their oil from Alaska, 40% of Canada's untapped oil reserves, 48% of untapped natural gas reserves are in the Arctic. I heard that there is enough oil there to supply the current needs for about 300 years. Whether that is bullshit or not I do not know.Stravo wrote: One of the reasons Canada needs those subs was to patrol the North West Passage. It is Canadian territory but Russia, U.S. and Denmark are clamouring that it is really international territory and to prove it, a few years ago the Russians launched a cruise missile (or was it an ICBM?) in a test in the Arctic, the Americans constantly go through the Arctic with their subs and the Danes gone through there with a few of their ships (I don't think it was military). They do not recognize the Canadian sovereignty over the Arcitc even though Canada has claimed it for about a century.
British Engineers: Making Americans look Brilliant for 200 years!Admiral Valdemar wrote:Don't make me come over there, Shep.MKSheppard wrote:Never ever buy british. At all. They suck major. Buy American, our shit blows
people up and works right
Do we even make Diesel boats anymore?MKSheppard wrote:Never ever buy british. At all. They suck major. Buy American, our shit blows
people up and works right
No,we haven't built them for a long time for the simple reason that they're not worht the effort for the US Navy. The US's sub doctrine since the Pacific has been to take the war to the enemy, and nuclear subs are far, far more capable of doing that.Stravo wrote:Do we even make Diesel boats anymore?MKSheppard wrote:Never ever buy british. At all. They suck major. Buy American, our shit blows
people up and works right
