Fire Control

[Werner]

I believe you're referring to the common attribution to von Neumann.

In fact, he invented the offine stored program and the mechanism to put it into main storage so the computer itself could access it.

The post office computer is more attributable to the US Constitutional requirement that an accurate census occur every decade for the purpose of determining proportional representation. Herman Hollerith (founder of IBM) rose to this task as early as 1890 and had reliable computers tabulating several simultaneous formulas by the 1930 census (the one with the Three Stooges in it). Computers suitable for fire control of this generation and could have been available, properly programmed in 1900.

My dad had a neat computer built around 1930 in Germany which was in the shape of a salt cellar with a crank on top. But that was a gentler era when the labor of calculation was beneath Herr Professor Doktor and properly the province of the unwashed graduate student (undergrads could not be trusted to spell their name, tie their shoes or comb their hair). You could tell the radicals in your class by the crease in their trousers.

Creation of the MIT RadLab, by the way, was the only significant set back to The Manhattan District Project (the A-Bomb), because Salizard and a number of others who had qualms about their science becoming a bomb to be dropped on Germany (and presumably Austria, Hungary, Czechoslovakia and so on), and were only too happy to apply to a project which worked on theoretically only locating the enemy, and not hurting him in any way.

A series of cavity magnetrons were lent to Nicola Tesla in Upstate New York, who announced by letter that he had determined a way to create a pulsed and focused coherent energy wave which could destroy a ship or plane, or formations of soldiers. Tesla was no crackpot, and when he died in 1944 the contents of his lab and writings were seized by the US Army and hidden away, presumably for a time when another human might approach his level of genius. His letter roughly describes a device known as a MASER, which is like a LASER, but predates it by approximately 20 years.

It would seem a total war with complete mobilization can be the most impressive catalyst for invention and scientific breakthrough ever known.

[Werner]

Incidentally, the anticipated performance for the radar system designed for Yamato (and partly installed before she sank) was roughly the same as the USN's CXAM-1, in that it might be able to detect a formation of high altitude bombers at 70 miles and a formation of destroyers at 12 miles.

Sadly, though, it was unable to detect an object roughly Yamato sized at 5-6 miles. The Japanese Army search set was so superior that it was mooted they obtain several sets for the fleet, but that level of cooperation was considered impossible by the Naval Staff.

[Laurence Batchelor]

"needed R&D", not true.
Read the histories.

One thing that I always get fractionally upset about, is that most believe that the US built the first "all electronic programmable computer", when in fact it was a Post Office engineer who achieved this feat in late 1943 at Bletchely Park.

The one with all the valves at Bletchely Park was the worlds first Super Computer I believe, there is a distinction
One only has to go to the Science Museum in London to see Sir Charles Babbage's mechanical contraptions they my friends are the world's first programmable computers, not what you see at Bletchely Park!

Yes Radar did need further RnD ar in the USA, it was far from perfected! Thats why there was a proliferation of new variants every few months in the war, they still hadn't got it spot on!

"...the British (British Patent GB593017 by Robert Watson-Watt in 1935), led to the first real radars. The war precipitated the research to find better resolution, more portability, more features etc etc'
Watson Watt is responsible along with a few others of mainly getting air detection radar going and acredited for equipping Britain will all her Chain Home stations in 1940 and getting the operatives trained in there use, so vital in the Battle of Britain.

Of course the next major development in the history of radar was the invention of the cavity magnetron by John Randall and Harry Boot of Birmingham University in early 1940.

But when these fellows went over to the USA they still didn't have a workable Centimetric radar.
They'd made a discovery but it still needed further work.
That was developed by them at the US Naval Research Laboratory by them inventing a duplexer switch allowing a pulse tranmitter and receiver to share the same antenna without destablizing the sensitive receiver.

Only with the combination of the magnetron, the duplexer switch, small antennas and high resolution allowed small high quality radars to be installed in aircraft, i.e. the working centrimetric radars used to deadly effective in the Battle of the Atlantic.

So yes very much RnD was needed in the US to perfect radar in my opinion, it was only workable in its infantile forms and was seriously under developed before the team went over to the USA.

If you have a different opinion I'd love to hear it please.

[ar]

I do have a different opinion to a degree but am currently hosting one R Short.

"needed R&D", not true.
Read the histories.

One thing that I always get fractionally upset about, is that most believe that the US built the first "all electronic programmable computer", when in fact it was a Post Office engineer who achieved this feat in late 1943 at Bletchely Park.

The one with all the valves at Bletchely Park was the worlds first Super Computer I believe, there is a distinction
One only has to go to the Science Museum in London to see Sir Charles Babbage's mechanical contraptions they my friends are the world's first programmable computers, not what you see at Bletchely Park!

Yes Radar did need further RnD ar in the USA, it was far from perfected! Thats why there was a proliferation of new variants every few months in the war, they still hadn't got it spot on!

"...the British (British Patent GB593017 by Robert Watson-Watt in 1935), led to the first real radars. The war precipitated the research to find better resolution, more portability, more features etc etc'
Watson Watt is responsible along with a few others of mainly getting air detection radar going and acredited for equipping Britain will all her Chain Home stations in 1940 and getting the operatives trained in there use, so vital in the Battle of Britain.

Of course the next major development in the history of radar was the invention of the cavity magnetron by John Randall and Harry Boot of Birmingham University in early 1940.

But when these fellows went over to the USA they still didn't have a workable Centimetric radar.
They'd made a discovery but it still needed further work.
That was developed by them at the US Naval Research Laboratory by them inventing a duplexer switch allowing a pulse tranmitter and receiver to share the same antenna without destablizing the sensitive receiver.

Only with the combination of the magnetron, the duplexer switch, small antennas and high resolution allowed small high quality radars to be installed in aircraft, i.e. the working centrimetric radars used to deadly effective in the Battle of the Atlantic.

So yes very much RnD was needed in the US to perfect radar in my opinion, it was only workable in its infantile forms and was seriously under developed before the team went over to the USA.

If you have a different opinion I'd love to hear it please.

[Laurence Batchelor]

Well I'll still be here after you've finished hosting Randy.

[Werner]

The problem with this argument is we are lumping what amounts to several generations of devices, each nearly revolutionary in it's own right unter one term: radar

It would be like lumping every hand-held projectile device developed since 1300 into one group and trying to argue who invented it.

Each week brought incremental features from the 1939-era direction finding transciever to units which incorporate an American designed time calculator addition which greatly increase the precision of range estimating using the beam formed by the transmitter by counting the micro seconds the radio signal travelled and converted that to feet or meters. Later, improvements in wiring allowed the receiver device to be somewhere other than nearly directly under the antenna. Further improvements created the Position Plot Indicator, which turned a series of wavy lines on an ocilloscope into a map-like screen, which greatly reduced the training requirement for the operators. Beam forming electromagnets and other aids controlled the scatter and random emissions of radar improving accuracy while reducing the possibility of interception.

Until the end of the war every week saw such massive improvement that GE, SCR, Westinghouse, Collins and so many others had thousands of technicians serving on ships and planes of all descriptions in the combat theatres in order to improve the art. Washington DC deserves a monument to the technicians of all types who died under enemy fire to improve the art of warfare in WW.II.

[chuck]

Chuck's writing on the Japanese culture seems to imply the combat officers would rather apologize and take the blame for the failure rather than blame the equipment or the system.

It's their code of honour afterall. Naval designers took the blame for themselves after the Tomozuru incident for instance. If it's right or wrong I don't know but it was their choice and problem.

Fujimoto was fired. He didn't "take the blame" voluntarily.

[chuck]

Do you think Filipe when the IJN developed the oxygen 24inch Long Lance torpedo in the 1930s they realised how reliant they would become on them in WW2?

Is it just possible they started to realise their large-calibre (long-range especially) firing was a bit pants.
Rather than spend the long time required to cure their gunnery problems, be them barrel or F/C related which could mean lengthy refits and 'retro-fitting' the whole fleet they decided to just really change their doctrine and make the torpedo their primary offensive weapon?

Just a thought!

Nonsense. They developed outsized oxygen torpedo because they were under the mistaken impression that RN had already developed and deployed a similar torpedo in the form of the 24.5 inch torpedo in the Nelson. Once you developed a 50 knot torpedo with a range in excess of 40,000 yards, naturally you begin to rebalance your notion of decisive weapon between torpedos and guns.

It was only later that they realised that in fact their torpedos were not playing catch up, but were in fact world leading.

[chuck]

Filipe,

'Large calibre' doesn't mean 5-inch guns on a destroyer I was speaking of cruisers!

In some cases the Long-Lance proved decisive others times a ticking time-bomb. I think you and the IJN attached too much importance to it.
They put all their eggs into 1 basket.

In hindsight it would have been better for the IJN to invest all that time, money and development in the 1930s into radar.
That way all of their capital ships may have been so fitted by 1942.

Also it seems a bit of a material waste to go to all the trouble to mount (sorry I'll rephrase that squeeze!) 10 8-inch barrels onto a relatively small hull and then up your torpedo armament and make that the weapon you most wish to use.

Japan's electronics industry was not sufficiently advanced for them to independently assess the real potential of radar. Considering their electronic industry overall was on a par with that of Italy, the quality and quantity of IJN electronics equipment actually deployed speaks of a very concentrated effort.

[Werner]

Thinking about fire control, 3-4 hits scored among 50 shots fired at 20,000 yards isn't all that much better shooting, except it is against a non-maneuvering enemy who believes themselves to be undiscovered.

Of course, since these are 24 inch torpedos, each hit is a kill and worth the waste, I guess.

[chuck]

Thinking about fire control, 3-4 hits scored among 50 shots fired at 20,000 yards isn't all that much better shooting, except it is against a non-maneuvering enemy who believes themselves to be undiscovered.

Of course, since these are 24 inch torpedos, each hit is a kill and worth the waste, I guess.

3-4 hits out of 50 fired at 20,000 yards is a better hit ratio than normally demonstrated by any naval artillery. The original intention was to fire about 400 torpedos at the US Pacific fleet battleline just before the on-set of the artillery battle. The longer range of the volley being compensated by the much bigger target profile. At that hit rate 24 torpedos can be expected to hit and take out at least 3-4 battleships, which would go most of the way to removing the initial 5:3 battleship advantage enjoyed by the US.

[Werner]

3-4 hits out of 50 fired at 20,000 yards is a better hit ratio than normally demonstrated by any naval artillery.

Quite true, but the 24-inch torpedo was the Tomahawk of it's day, and one torpedo cost Japan more than several main battery salvos, so you would have to discount the cost of the engagement thusly.

Of course any naval engagement where your motion at the end is horizontal and your enemy's is vertical is a victory no matter what the cost.

Too bad Yamato never hit anything. It would have made for interesting calculus regarding cost/benefit. As it is, she remains one of the most modeled, completely worthless ships of war. Even Tirpitz can't make that claim.

[chuck]

The primary weakness of Japanese naval artillery fire control, other than lack of Radar FC, was the requirement for large amount highly trained crew operation. The theoretical maximum capabilities of Japanese range finding, shot spotting and range keeping were on a par with what is developed in the US. However, Japanese fire control was not centralized, and requires large amount of manual transmission of data from one step to another. So the system is much more vulnerable to crew fatigue and is much more impacted by poor crew training.

Regarding the behavior of Japanese cruiser fire in 1943, I suspect it has to do with poor manual intervention in range keeping. The Japanese fire control involve a device which plots multiple range forecasts based on multiple different reads and sources. The operator manually examines the range plots and discards what he judges to be unreliable plots. The device then average the remaining range plots for transmission to the director. Obviously the man with the power to discard plots must both have good access to information of results of current firing, as well as training adaquuate to judge what would likely be a good range reading and what is likely to be spurious. If, when a series of solvos have all been unsuccessful, and he is called upon to improve the range solution, either his training or his oversight causes him to consistently discard the wrong set of range reads, then I imagine the next solvo's accuracy will suddenly deterioate.

This will explain the improve - improve - improve - decay pattern seen in some Japanese cruiser fire.

[Werner]

Quite a possible scenario. The pattern was noted in 1942 as well, so perhaps at some point the decision table is defective.

I regard a British built-in defect as unlikely. It reminds me of a story in the early 1970s that a British officer in Whitehall could press a button and the location of every USSR submarine was displayed on a projection map.

The story goes that MI6 had infiltrated the USSR ship design directorates to such a point that the Soviet ship builders actually installed transponders for Whitehall as ordered by the design bureau!

[chuck]

3-4 hits out of 50 fired at 20,000 yards is a better hit ratio than normally demonstrated by any naval artillery.

Quite true, but the 24-inch torpedo was the Tomahawk of it's day, and one torpedo cost Japan more than several main battery salvos, so you would have to discount the cost of the engagement thusly.

One torpedo hits is worth at least 3-4 well aimed solvos, especially considering the hit rate in well aimed salvoes is about 1 - 2 hit out of 3-4 solvos at 20,000 yards.

[Werner]

Quite true, but the 24-inch torpedo was the Tomahawk of it's day, and one torpedo cost Japan more than several main battery salvos, so you would have to discount the cost of the engagement thusly.

One torpedo hits is worth at least 3-4 well aimed solvos, especially considering the hit rate in well aimed salvoes is about 1 - 2 hit out of 3-4 solvos at 20,000 yards.

Like I said, if at the end of the engagement your motion is horizontal and the enemy's is vertical, the cost is unimportant.

[chuck]

It's their code of honour afterall. Naval designers took the blame for themselves after the Tomozuru incident for instance. If it's right or wrong I don't know but it was their choice and problem.

Fujimoto was fired. He didn't "take the blame" voluntarily.

Incidentally, all of the top heavy Japanese cruiser and destroyer designs were attributable to Fujimoto. The Japanese cruiser got lighter in construction and more questionable in stability the more Fujimoto was promoted. His first completely autonomous cruiser design not subject to the review of Hiraga his mentor and the navy board was the Mogami, whose hull was so flexible and bends so much in heavy sea that it actually deform the main caliber barbettes into ovals so the turrets jammed in train.

Watching that ship work in heavy seas must be like watching the wings of passenger planes flex in rough air.

Incidentally, his thinking was very advanced. His ships flex like modern ships. But he didn't work out all the consequences of having such a flexible hull.

[Guest]

The notion that Japanese knew of their own gunnery deficiencies prior to WWII was also untrue. The Japanese had in fact planned on engagements out to beyond 38,000 yards and excercised accordingly. When Yamato first joined the combined fleet in 1942, she participated in an fleet exercise where she failed to hit (Definition of "Hit" is unclear) a target at 38,000 yards. This was considered a grave disappointment for the brand new battleship. Apparently at first it was felt that equipment performance expectation was not met and thus the inexperience of green crew was no excuse - Yamato class having the best fire control equipment in the IJN. Nevertheless a range keeper was later blamed for failing to properly use his intrument correctly. The next instance I know of when Yamato engaged in a super range firing exercise was 1944, when she, along with Musashi and Nagato successfully engaged a target at 38,000 yards - Again, definition of success is unknown to me.

The fact the Japanese exercised successfully by their own measure at such extreme range and yet seemly performed in battle mostly below expectation at closer range suggests to me that Japanese fire control is physically capable of very good performance, but lack the robustness to exhibit maximum performance in battle.

[phil gollin]

The cavity magnetron came to the USA in a leather satchel in 1940, a gift of the British Government. Later in 1940 they sent Edward George Bowen who opened the MIT Radiation Lab. Half of all radar instruments deployed by the allies in WW.II came from the RadLab.

Not only the cavity magnetron.

The Bailey committee ensured that ALL british radar designs and samples of almost all radar equipment was sent over to the US in late 1940/early 1941.

In addition three US electrical engineers were sent over in late 1940 to examine all British all radars and look around the experimental establishments.

[Laurence Batchelor]

Nonsense. They developed outsized oxygen torpedo because they were under the mistaken impression that RN had already developed and deployed a similar torpedo in the form of the 24.5 inch torpedo in the Nelson. Once you developed a 50 knot torpedo with a range in excess of 40,000 yards, naturally you begin to rebalance your notion of decisive weapon between torpedos and guns.

It was only later that they realised that in fact their torpedos were not playing catch up, but were in fact world leading.

I wasn't being serious merely taking a light hearted approach to their doctrine

How often did IJN warships undertake gunnery practice?