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Suppose you have a reasonably competent pilot, with reasonable hardware, on a reasonable day, an no one shooting at him (so maybe in training). How accurate was dive bombing? How likely would it be to hit a ship, or a pill box?
Hate to be a pedant but doubling the diameter/radius doesnt double the size of the target. 50x50=2,500 100x100= 10,000, it just doubles the distance from the aim point the area is 4 times bigger.Here's some info where F4U's and SBD's were compared as dive bombers against land targets. The F4U lowered its landing gear for dive brakes. Apparently the F4U's landing gear was designed to take the stresses, as the usual 'max speed with gear down' restrictions didn't apply.
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Hate to be a pedant but doubling the diameter/radius doesnt double the size of the target. 50x50=2,500 100x100= 10,000, it just doubles the distance from the aim point the area is 4 times bigger.
The German shipborne radars used a fairly narrow beam radar and would have to have the receiver/transmitter aimed at the aircraft in order to detect it. There is no evidence via Tirpitz's War Diary (March 1942) that she was able to detect aircraft at long range via radar.
The Japanese magnetron was not the same design as the cavity magnetron developed by the UK (Randall and Boot) and was never capable of generating high power output.
Seetakt was detecting aircraft from its inception, in 1935. Both a Freya radar and a Seetakt radar (at the German naval station at Whilhemshaffen) detected an inbound raid of Wellingtons that was almost completely destryed by Me 109 interceptors. The two radar operators contacted each other. A Beam width of 6 degrees is adequate for detecting aircraft.
On the day of operation Catechism, the Lancaster bomber raid that sank Battleship Tirpitz the ships radar detected the Lancaster's at 150km range (see Niklas Zetterling book on Tirpitz) and provided Tirpitz's first warning.
Tirptiz was sunk because the Luftwaffe did not intercept due to a a combination of bad luck, Ju 52 landing on the fighters runway and likely espionage at the Luftwaffe's Wassermann radar station.
By 1942 Kreigsmarine u-boats were getting FuMO 61 Hohtenweil radars which had a mattress aerial in the side of the conning tower, in 1943 small ships received it and latter in the year Hohtenweil received a full PPI (Plan Position Indicator) referred to as a panorama display. Tirpitz received a hohtenweil as did Prinz Eugen.
In 1944 some ships (torpedo boats) and larger units such as Bismark and also Prinz Eugen also received FuMo 81 Berlin 9cm microwave radars.
Whatever is in the war diary would be cryptic as radar would only be referred to peripherally, likely as EM-2 (range finder 2,the code word for radar on German ships) and in any case German navy tended to maintain radio and radar silence.
As you state the UK magnetron was a very different design. RN Type 271/273 had a much longer range due to the higher power output, and range was essentially horizon limited. Duke of York's Type 273 detected Scharnhorst at ~41km, when only her upper superstructure was above the horizon. The IJN Type 22 vastly inferior.The Japanese magnetron worked in exactly the same way: circular cavities with round slits. The Japanese even developed strapping. The difference was that the British magnetron was machined out of a solid copper block with water cooling into the main copper whereas the Japanese magnetron was fabricated and installed in a glass case to maintain vacuum and lacked water cooling. There are pictures around and I have a $500/book folly published by the IEEE.
The Japanese type 22 radar had the same range, about 24km which they achieved by using a long pulse of about 10 micro seconds leading to an range accuracy of about 300m.
The Japanese did develop more powerful magnetrons including water cooling (in development). They also introduced lobe switching using 3 horn antenna (central transmit, left and right receive) .
There are a lot of radar myths out there.
If there had of been fortnightly curior flights between German and Japan its likely the Germans would have become aware of the Japanese microwave radar and it would have helped them immensely.
As you state the UK magnetron was a very different design. RN Type 271/273 had a much longer range due to the higher power output, and range was essentially horizon limited. Duke of York's Type 273 detected Scharnhorst at ~41km, when only her upper superstructure was above the horizon. The IJN Type 22 vastly inferior.
Tirpitz's War Diary makes no mention of radar detection of aircraft.
What shore based radar could do is not really relevant. KM shipborne radar was broadly equivalent to RN Type 284. Yes, type 284 could detect aircraft, but is was terribly inefficient at it because of the narrow radar beam which meant that the director upon which it was mounted would have to be rotating constantly to scan the horizon. Tirpitz, by 1944 was a static shore battery and was given, the equivalent to a shore based radar installation. RN type 79 was operational in 1938 and was a dedicated long range AW radar. Type 279, was similar but had a FC ranging unit added to it. It was used operationally from 1940.
At the end of the war both USN and Luftwaffe were trialling toss bombing sights.
No, the UK magnetron didn't work in different ways. It used circular cavities and narrow slits. The physics was the same. It had water cooling and was solid copper that is what allowed it to operate at much higher power levels. Dr S.Nakajima who headed JRC (Japanese Radio Company) department that developed these radars amongh other complained in the IEEE book "Radar Development to 1945" that he started the war with a workforce of 800 and ended it with 400. He said "The Japanese military had no basic policy in drafting personnel" and that many ended up as foot soldiers. This is what stopped them refining their product. The Japanese did develop type 32 which offered 35km range (essentially to the horizon) and had lobe switching for blind fire control. It still used the 2kW magnetron. It was simply physically larger antenna. Dr Nakajima said JRC had a solid metal water cooled magnetron ready in 1945 but said "we couldn't move on it because there was no allocation of materials for it. From the first radar to the last the Japanese military didn't allocate the nickel for the magnets or the copper for the magnetrons. They also had PPI. The Japanese radar also functioned as a radar detector with the transmitter switched off.
UK type 284 radar was originally 25kW and rather unreliable due to requiring a 20 minute warmup time and a shutdown after a few hours. The Germans had non of these problems and their 1.5kW and 8kW radar had the same range. As continuous use was possible there was no problem with using them as search radars for aircraft and surface search. The Seetakts used grid modulation and a longer pulse to get the range but recovered accuracy from the greater precision of the grid modulation circuit and phase recovery. The UK radars overcame these latter problems and Type 284M and Type 284P started appearing around 1942 with 125kW pulse and lobe switching to allow blind fire.
The Seetakt received a 125kW modulator in 1942 as well but only on land based "Calais" versions. This is because Seetakt up until then had used grid modulation to turn the pulse on and off as well as generate the wave whereas the British radar used anode modulation in which the grid generated the wave but the pulse was created by pulsing the whole valve like a spark plug. Hence the Germans tried this first on land based installations due to the high voltages required and planed a latter installation at sea.
When Scharnhorst encountered Burnetts three cruisers and then Duke of York (DoY) during the Battle of North cape it was very bad timing for the Germans as Scharnhorst just missed out on radar upgrades that were a few months away at most.
1 Firstly note that the Germans were outnumbered and had to observe radio silence whereas the British being the superior force could keep their radars on.
2 In All encounters German passive radars (or infrared) detected the British radar (both the cruisers and Duke of York) and gave sufficient warning for the German crews to at least get to action stations and start the process of getting their guns pointing in the correct direction. The German microwave warning device Naxos was also unreliable at this time.
3 The forward facing Seetakt was damaged in the encounter with the cruisers but the rear radar was working. It could detect the British ships and direct fire against them but at the great ranges involved the German radar could not see the shell splash and correct aim whereas the British with their bigger shells and more powerful radar could (although Scharnhorst pulled away and got out of shell splash radar range when a lucky shot ( moments before DoY was about to give up) hit a shot trap near her engine room and slowed her down.
4 The emphasis for the German navy was improving radar on its u-boats. The three capital ships the
Tir[pitz, Scharnhorst and Prinz Eugen had to wait. Scharnhorst thus missed out on the Backup Hohtenweil PPI radar being fitted in 1943 to u-boats and torpedo boats latter fitted to Prinz Eugen and Tirptiz as well as the FuMO 81 microwave surface search radar towards the end of 1944.
5 The 8kW 24km range FuMO 26 was supposed to be replaced by the 125kW FuMO 34 which could detect to the radar horizon and sport shell splash to it (due to its long shaped pulse). It seems Tirpitz had a 125kW pulse as a 'one off' since it could detect the incoming Lancaster raid at 150km.
Hence those imagining Bismarck battling a KGV or Iowa class in late 1944 or early 1945 should consider with a late war fitout more or less matched them or nearly so. (Iowa's 1945 fitout is pretty impressive because its radar could spot shell splash over the visual horizon not only for range but bearing deviation)
Seetakt was modified to both have a surface search, support air search, anti aircraft fire control and blind fire ability with multi role antena.
Type 79 and Type 279 were long wave radars that could not detect a surface submarined or a periscope nor could they be fitted to smaller ships. This made British convoy escorts fairly ineffective at the start of the war. Seetakt could do all of this and on a 1000 ton torpedo boat. It may not have been the best air warning radar but it did perform that job effectively. As I have pointed out the Krieksmarine supplmented its radars with a Hohtenweil PPI type from 1943-1944 and with a microwave type called FuMO 81 from late 1944 onwards.
Under those conditions, in an SBD, I'm going with pill box. That's how good that bad boy was. Those cadets were hitting die markers in the Gulf of Mexico, 4 for 5 and 5 for 5. My Dad's docket shows the runs and scores he and his "crew" got. But I heard it in his retiree club, too, and how much the pilots loved that "Speedy D," whether it was the one they ended in, or just trained some in. So, put me down for pill box in the poll.Suppose you have a reasonably competent pilot, with reasonable hardware, on a reasonable day, an no one shooting at him (so maybe in training). How accurate was dive bombing? How likely would it be to hit a ship, or a pill box?
(this is a bit off topic) The one good thing about dive-bombing compared to the torpedo bombing (if you wanna take out a ship) was as a dive bomber you would start at a higher altitude and you would be moving very fast throughout the bombing run while torpedo bombers had to be slow a low to the sea level.
Although the "very fast" part is not all that true - Stukas, SBDs, A-36s, Vals, etc. all deployed dive-brakes that limited their dive speed.Versus carriers, sure -- assuming you caught them at the right time.
Although the "very fast" part is not all that true - Stukas, SBDs, A-36s, Vals, etc. all deployed dive-brakes that limited their dive speed.
The SBD's massive dive-brakes held it steady at 250mph in it's 70-80 degree dive.
The Stuka was about 350mph in it's near-vertical dive.
The A-36 Mustang was about 390mph and the D3A 273mph.