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aj906
07-08-10, 06:01 AM
Just a quick question...

U-185 is a Typ IX/C and its now Nov '43. I had radar installed as soon as I could on the conning tower. I've not upgraded because, frankly, I've never had a radar contact. My FuG (1942 version) works just fine and detects other radar signals (although there are times I've been "seen" without warning in heavy seas and low visibility).

My question is, how does the radar work? It cost however much renown and has proved useless in 'seeing' ships my watch cant. Am I mistaken into thinking the sweep it does over the horizon is for detecting radar signals and not ships or is there a trick to getting the thing to work?

I'm playing GWX 3.0 with no extra mods (if only cause I'm technologically incompetent and don't know which is which and what to do with them once I have them!)

Gerald
07-08-10, 06:23 AM
Just a quick question...

U-185 is a Typ IX/C and its now Nov '43. I had radar installed as soon as I could on the conning tower. I've not upgraded because, frankly, I've never had a radar contact. My FuG (1942 version) works just fine and detects other radar signals (although there are times I've been "seen" without warning in heavy seas and low visibility).

My question is, how does the radar work? It cost however much renown and has proved useless in 'seeing' ships my watch cant. Am I mistaken into thinking the sweep it does over the horizon is for detecting radar signals and not ships or is there a trick to getting the thing to work?

I'm playing GWX 3.0 with no extra mods (if only cause I'm technologically incompetent and don't know which is which and what to do with them once I have them!)

http://static.howstuffworks.com/gif/radar-intro.jpg

Neither a single nation nor a single person is able to say, that he (or it) is the inventor of the radar method. One must look at the „Radar” than an accumulation of many developments and improvements earlier, which scientists of several nations parallelly made share. There are nevertheless some milestones with the discovery of important basic knowledge and important inventions:

1865 The English physicist James Clerk Maxwell developed his electro-magnetic light theory (Description of the electro-magnetic waves and her propagation)

1886 The German physicist Heinrich Rudolf Hertz discovers the electro-magnetic waves and prove the theory of Maxwell with that.

1897 The Italian technician Guglielmo Marconi bridged larger distances with electromagnetic waves. As a radiating and receiving aerial element he used a long pole, along which was carried a wire. In Italian a tent pole is known as l'antenna centrale, and the pole with a wire alongside it used as an aerial was simply called l'antenna. Today Marconi is known as pioneer of radio communication.

1904 The German high frequency engineer Christian Hülsmeyer invents the „Telemobiloskop” to the traffic supervision on the water. He measures the running time of electro-magnetic waves to a metal object (ship) and back. A calculation of the distance is thus possible. This is the first practical radar test. Hülsmeyer registers his invention to the patent in Germany and in the United Kingdom.

1921 The invention of the Magnetron as an efficient transmitting tube by the US-american physicist Albert Wallace Hull

1922 The American electrical engineers Albert H. Taylor and Leo C. Young of the Naval Research Laboratory (USA) locate a wooden ship for the first time.

1930 Lawrence A. Hyland (also of the Naval Research Laboratory), locates an aircraft for the first time.

1931 A ship is equipped with radar. As antennae are used parabolic dishes with horn radiators.

1936 The development of the Klystron by the technicians George F. Metcalf and William C. Hahn, both General Electric. This will be an important component in radar units as an amplifier or an oscillator tube.

1939 Two engineers from the university in Birmingham, John Randall and Henry Boot built a small but powerful radar using a Cavity-Magnetron. The B- 17 airplanes were fitted with this radar.

1940 Different radar equipments are developed in the USA, Russia, Germany, France and Japan.

Driven by the common war expiry and the general development of the air forces to meaning key players radar technology undergo a strong development push during the 2nd's World War and is used during the „cold war” in large quantities along the german domestic border.



http://www.youtube.com/watch?v=MmhmoLMhO1Y



RADAR (Radio Detection And Ranging) is a technology invented in the 1930s to detect distant objects, mostly aircraft and ships. Since detection is done by receiving radio waves reflected from the target, radar works the same by day and night and in all weather, which makes it a revolutionary long range observation tool, both military, and after world war 2, also civilian.
World war 2 radar technology

Radar works essentially in the same way that a bat uses sound to 'see' in total darkness. The radar transmitter produces strong (kilowatts) and extremely short (about a millionth of a second) pulses of radio energy. The pulses are transmitted thru the air to a known direction by a directional antenna. When pulses hit an object, such as an aircraft, a ship, or the ground, they are reflected by it. The reflections are received by the radar antenna, and converted by a receiver to an electric signal that can be displayed to the operator. Since the speed of the signal is the speed of light, the time between the transmission and the reception of a pulse indicates the distance of the target, and together with knowing the direction at which the antenna transmits, the position of the detected target is known.

Initially radars were equipped with display devices like those in an electronics lab (oscilloscope), but later more operationally useful devices were invented, particularly the PPI (Plan Position Indicator) which is the familiar radar display in which a circular display shows a beam which rotates with the rotating radar antenna, and marks with light the positions of detected targets relative to their range.

Electronically, PPI works basically like the lab oscilloscope display, but because of the rotation it creates a map-like display that the operator understands intuitively and immediately, as if he was looking at a map where the radar's own position is in the centre, and the map position of detected targets are marked with small dots of light. The operational advantage of this display method was enormous, because it eliminated the need to calculate and check directions on a map. PPI is the map that shows the operator clearly where the targets are.

From military point of view there are basically two types of radar, used for detection and for fire control.

Detection radars are used to create a radar map of all objects in all directions and often as far as possible. They are mostly used for purposes such as early warning detection of aircraft and ships, ground controlled intercept of aircraft, which is done by directing fighter aircraft to detected incoming aircraft, and mapping of the ground terrain for navigation and targeting, mostly by bombers.

Fire control radars are the radar equivalent of a searchlight. They are dedicated to the precise positioning of a previously detected particular target, precise enough to aim guns at it and hit it without actually seeing it, or at least to guide the operator so close to it that it finally can be seen, even if only as a dark shadow, and then to aim guns at it and hit it. Fire control radars were used mostly by night fighters, which were usually twin engine aircraft, larger than day fighters, which could carry not just the pilot but also a heavy radar, a radar operator, and were heavily armed in order to make sure that the target, a heavy bomber, will be destroyed by the first burst of their guns, because unlike day fighter pilots which could pursuit their target, night fighter pilots could 'see' only the narrow cone ahead of them that was 'lit' by their radar, and unless the target was destroyed, its pilot could immediately break away into a deep dive or other evasive manoeuvres and unless it was burning it could quickly disappear in the darkness.

An interesting combination of using a radar and a searchlight for fire control was used in anti-submarine aircraft which hunted German submarines in the Atlantic. After a surfaced submarine, or even just the periscope of a submerged submarine, was detected by radar, the radar operator guided the pilot to it, but since it was such a small target, and one that had to be precisely hit in the 1st attempt or it would disappear, and since radars can't detect below a certain minimum range, the aircraft pilot just had to see the target with his eyes in order to direct the aircraft right over it and drop the depth charges at the right moment. To be able to do so at night, these bombers carried a powerful fixed searchlight aimed forward, and it was lit in the last few seconds. Early enough for the pilot to actually see the target on the water ahead of him, and too late for the submarine to dive.
Electronic Warfare and Electronic Intelligence

The greatest advantage of using radar is that it denies the enemy of the ability to use the element of surprise, of being hidden by distance, by night or by clouds until it's too late to defend against it or to attack it before it disappears. The response was obvious, the side that wanted to avoid being detected by radar wanted to know if and where it was being detected by radar, and also to be able to neutralize enemy radar in order to regain the element of surprise. This started a dramatic and secret electronic arms race between radar developers and those who develop measures against radar, an arms race which continues since world war 2.

The first development was radar detectors. The basic types, carried mostly by bombers and submarines, could tell their operators if a radar was transmitting at them (and therefore could detect them) and could estimate if it was near or distant, by the power of the radar waves. The more advanced radar detectors were used to analyze everything possible about enemy radars, their power, radio wave frequency, pulse rate, pulse width, and other technical parameters from which engineers could learn a lot about the capabilities of enemy radars, and design 'electronic warfare' counter-measures to use against them.

They could also help determine where enemy radars were positioned, so they could be attacked, or bypassed, or in one special case, stolen! - in late 1941, British intelligence noticed that one German early warning radar position, in Bruneval, Belgium, was positioned very close to the beach. It was on a cliff, but not far from a path going down to the water. This was enough for British commandos to raid the isolated German radar station in Bruneval one winter night in 1942, dismantle the radar, with the help of a radar specialist who came with them, and take it all back to England in a motor boat, for a complete analysis of this particular type and of German radar technology in general. (this bold idea was repeated in 1969 when Israeli commandos dismantled and lifted a radar in Egypt with helicopters)

Once much is known about enemy radars, they can either be attacked, if they're in range for a precision attack by dive bombers or fighter-bombers, or more commonly they can be disrupted by electronic warfare, which in world war 2 included two main types of counter-measures: jammers transmit strong radio waves in the same frequency as the radar, which saturate the radar receiver with signals so much that it can't see the weaker signals of real targets. chaff (nicknamed 'window' by the royal air force) are a cloud of thin lightweight strips of metal cut to a specific size, which can be dispersed from a heavy bomber. These strips are designed to be detected by radar and therefore instead of detecting isolated real targets, the radar operator sees just a huge cloud. There are various ways for radar operators and designers to partially counter these counter-measures, partly by having highly trained and experienced operators, partly by technological solutions, and partly by direct action, using radar detectors on night fighters to locate and destroy the jammer-carrying aircraft.
Notable world war 2 radar types

*

Freya - a German early warning radar used to detect formations of allied bombers (range: 125 miles)


Funkmessgerät Typ. Freya - with two antenna systems, one for horizontal and one for vertical use


Freya fitted to a German night fighter

*

Wurzburg - a German GCI (Ground Controlled Intercept) radar used to direct fighters, especially night fighters, close enough to enemy bombers that their pilots could then independently intercept them, visually at day, or by radar at night (range: 18 miles)


Würzburg-Riese radar

*

Lichtenstein SN2 - the radar of the German night fighters (range: 2.5 miles)


Lichtenstein BC fitted to a Ju 88

*

Chain Home - a network of British early warning radars used to defend Britain in the Battle Of Britain. It was an early and primitive radar, but it was powerful and reliable, and was efficiently operated by experienced operators, and therefore was a critical asset which allowed the British Fighter Command to optimally engage incoming German bomber formations. (range: 185 miles)


Chain Home radar masts

*

ASV (Air to Surface Vessel) - this airborne radar very dramatically increased the ability of maritime patrol aircraft to detect German submarines in the wide Atlantic ocean and attack them, and was therefore a critical element in the battle of the Atlantic.


ASV (Aircraft to Surface Vessel) radar was tested in Avro Ansons

*

SJ - the radar used by American submarines to detect Japanese ships and aircraft at night and in bad weather.

*

H2S - a ground mapping radar used by allied bombers for navigation and targeting in long range missions. German night fighters used radar detectors to detect H2S transmissions in order to intercept the bombers despite the electronic warfare against the German radars.




* Before World War II, experiments were performed with electronic systems to find the range of aircraft or other targets by transmitting radio pulses and measuring the time delay in receiving an echo back from the target. During the war, "radio detection and ranging (radar)" went through a rapid evolution and became an important weapon and tool in the conflict, with the opponents developing radars of increasing sophistication -- as well as "electronic intelligence (ELINT)" systems to spot enemy radars and "electronic countermeasures (ECM)" systems to jam them.

By the end of the conflict, radar systems had advanced to a level inconceivable before the war, and have continued to be refined in the postwar era. Radar remains an important military and civil technology. This document provides an introduction to radar concepts and terminology.

Gerald
07-08-10, 07:45 AM
Just a quick question...

U-185 is a Typ IX/C and its now Nov '43. I had radar installed as soon as I could on the conning tower. I've not upgraded because, frankly, I've never had a radar contact. My FuG (1942 version) works just fine and detects other radar signals (although there are times I've been "seen" without warning in heavy seas and low visibility).

My question is, how does the radar work? It cost however much renown and has proved useless in 'seeing' ships my watch cant. Am I mistaken into thinking the sweep it does over the horizon is for detecting radar signals and not ships or is there a trick to getting the thing to work?

I'm playing GWX 3.0 with no extra mods (if only cause I'm technologically incompetent and don't know which is which and what to do with them once I have them!)
:up:

Jimbuna
07-08-10, 08:29 AM
Just a quick question...

U-185 is a Typ IX/C and its now Nov '43. I had radar installed as soon as I could on the conning tower. I've not upgraded because, frankly, I've never had a radar contact. My FuG (1942 version) works just fine and detects other radar signals (although there are times I've been "seen" without warning in heavy seas and low visibility).

My question is, how does the radar work? It cost however much renown and has proved useless in 'seeing' ships my watch cant. Am I mistaken into thinking the sweep it does over the horizon is for detecting radar signals and not ships or is there a trick to getting the thing to work?

I'm playing GWX 3.0 with no extra mods (if only cause I'm technologically incompetent and don't know which is which and what to do with them once I have them!)

I've no idea what you are referring to with "Fug" but the readar and sensors are explained in the manual that came with the mod....pages 67 - 71.

maillemaker
07-08-10, 11:57 AM
I've never had much luck with radar, either. Especially in rough seas / poor visibility, which is when you want it the most. The problem is every time the water touches it it turns off the radar!

I find radar WARNING to be much more useful. It does not give away your position, but is nearly as good for finding THEIR position.

Steve

Gerald
07-08-10, 05:21 PM
I've never had much luck with radar, either. Especially in rough seas / poor visibility, which is when you want it the most. The problem is every time the water touches it it turns off the radar!

I find radar WARNING to be much more useful. It does not give away your position, but is nearly as good for finding THEIR position.

Steve RWR was better in a different way,but as you say give not, position! :yep:

Snestorm
07-09-10, 08:35 AM
I've never had much luck with radar, either. Especially in rough seas / poor visibility, which is when you want it the most. The problem is every time the water touches it it turns off the radar!

I find radar WARNING to be much more useful. It does not give away your position, but is nearly as good for finding THEIR position.

Steve

It's one of the things that got "fixed", when it wasn't broken.

In my original install it worked fine, and kept me from getting run over in heavy fog.

My newer (Encore) installation "fixed" it, by rendering it completely useless in rough seas, and while using time compression.

Note: Overall, Encore has fixed, and improved alot.
So in exchange for all the good things, I can endure the radar "improvement". (I'm considering ommitting radar from my purchases, as it truely has been made useless.)

I hope the radar detector didn't get the same treatment.

maillemaker
07-09-10, 10:15 AM
What is Encore?

Steve

Snestorm
07-09-10, 12:07 PM
What is Encore?

Steve

If you get the SH2 SH3 combination from Amazon, it's distributed by Encore, through some kind of deal with UBI. It already comes patched to 1.4, and without Starforce, which was why I bought it.

After uninstalling my original purchase, and installing the Encore release, I learned that it was modded, repaired, and for the most part, improved.

The first thing I noticed was the ports. My original install didn't show any of the piers and things on the nav-chart, nor did the nav-chart perfectly match visual immage from the bridge. The new install showed everything about the ports in great detail.

The next thing I noticed was all the neat new nav-tools, which weren't in my original install.

Next to be noticed was, no more game crashes. And I could finaly "Save and Exit", which my original install didn't allow.

There is more, but I modded so much that I can't remmember them all.

The only minus I can think of is "fixing" the radar, that wasn't broken.
(minor when looking at all the pluses, no?)

I think they fixed the diving depths of the variouse boats as well, but haven't been brave or desperate enough to test it.

Gerald
07-09-10, 12:30 PM
If you get the SH2 SH3 combination from Amazon, it's distributed by Encore, through some kind of deal with UBI. It already comes patched to 1.4, and without Starforce, which was why I bought it.

After uninstalling my original purchase, and installing the Encore release, I learned that it was modded, repaired, and for the most part, improved.

The first thing I noticed was the ports. My original install didn't show any of the piers and things on the nav-chart, nor did the nav-chart perfectly match visual immage from the bridge. The new install showed everything about the ports in great detail.

The next thing I noticed was all the neat new nav-tools, which weren't in my original install.

Next to be noticed was, no more game crashes. And I could finaly "Save and Exit", which my original install didn't allow.

There is more, but I modded so much that I can't remmember them all.

The only minus I can think of is "fixing" the radar, that wasn't broken.
(minor when looking at all the pluses, no?)

I think they fixed the diving depths of the variouse boats as well, but haven't been brave or desperate enough to test it. Nearby costline or bad condition,but the enemy unit can detect you,so this is more logical to use,when you really need this equipment,I turn I't of more to avoid some DD with "RWR" on.

Snestorm
07-09-10, 02:18 PM
Nearby costline or bad condition,but the enemy unit can detect you,so this is more logical to use,when you really need this equipment,I turn I't of more to avoid some DD with "RWR" on.

Our problem is that when we realy need it (bad weather - Heavy Fog), it doesn't work.

Bronzewing
07-10-10, 08:54 PM
I've noticed one important fact no one's mentioned here, the main reason radar on subs never seems to work is that you have to remember it's fixed to your conning tower. This means it doesn't scan, it just covers a narrow angle in front of you. So unless something passes in front of you, in range, while you have it on, you're not going to see it. I did once pick up a ship with it in medium fog, but calm sea. However this was only after spending the prevoius 30 hours driving my boat round and round and round in circles to rotate my boat's radar. :DL The crew were most releived as they were getting very dizzy! :doh: Sadly when we finally caught up with it, it was only an old coastal steamer that was hardly worth sinking, at least it wasn't neutral.

timmy41
07-10-10, 10:14 PM
I've noticed one important fact no one's mentioned here, the main reason radar on subs never seems to work is that you have to remember it's fixed to your conning tower. This means it doesn't scan, it just covers a narrow angle in front of you. So unless something passes in front of you, in range, while you have it on, you're not going to see it. I did once pick up a ship with it in medium fog, but calm sea. However this was only after spending the prevoius 30 hours driving my boat round and round and round in circles to rotate my boat's radar. :DL The crew were most releived as they were getting very dizzy! :doh: Sadly when we finally caught up with it, it was only an old coastal steamer that was hardly worth sinking, at least it wasn't neutral.
you are talking about the FuMO 29
http://www.uboat.net/technical/images/fumo29.jpg

there are also several others in game, that rotate. the FuMO 30, 61, and 65.

maillemaker
07-10-10, 11:53 PM
I've noticed one important fact no one's mentioned here, the main reason radar on subs never seems to work is that you have to remember it's fixed to your conning tower.

No, the main reason the radar never seems to work is that it automatically turns off whenever water hits the bridge.

So in inclement weather/heavy seas, when you are most likely to want to use radar, it won't stay on but for a minute or two before shutting down because water hit it.

Steve

Jimbuna
07-11-10, 07:19 AM
No, the main reason the radar never seems to work is that it automatically turns off whenever water hits the bridge.

So in inclement weather/heavy seas, when you are most likely to want to use radar, it won't stay on but for a minute or two before shutting down because water hit it.

Steve

Correct Steve...thus giving the game engine the impression you are submerged, hence no radar.

Snestorm
07-11-10, 08:20 PM
I think the difference between my two installs is this.:

In the original install the default setting was "On", unless I turned it off.
Thus, even after cotacting water, it would return to the default "On" setting.

In my newer install they changed the default setting to "Off".
Every time it makes contact with water it turns "Off", until you manualy turn it back "On".
The "improvement" was a mistake on somebody's part.

Captain Nemo
07-12-10, 07:01 AM
I had the FuMO 29 radar in a previous career and other than the problem of it switching itself off, I found that I had to man it myself because the Radio man wouldn't call out contacts like he does when he sits at the sonar station. Have others experienced this problem?

Nemo

Paul Riley
07-12-10, 09:03 AM
you are talking about the FuMO 29
http://www.uboat.net/technical/images/fumo29.jpg

there are also several others in game, that rotate. the FuMO 30, 61, and 65.

With it only covering a 10 degree arc to the front this particular set would be better off thrown overboard,not only is it practically useless you are lit up like a Roman candle on bonfire night (radar signature wise).The only POSSIBLE use would be in thick fog,but I would probably submerge anyway during said conditions.It could be useful in the bay of Biscay but only when returning! in the odd chance you may pick up incoming planes to your front (very risky) :ping:
My advice,switch off,unplug,rip out,throw into sea.
Maybe the later models are more effective.