Comments on: Automatic Aiming Cannon Could Hit Invisible Aircraft (Feb, 1929)

By: Firebrand38

Firebrand38 — Mon, 03 Aug 2009 23:05:25 +0000

Nice of you to say so. I try to make my self useful so Charlie will let me hang out.

I know what you mean about calculations. My favorite example is back in the 50′s when Lockheed engineers designed the A-12 using slide rules.

By: Jari

Jari — Mon, 03 Aug 2009 22:23:28 +0000

Firebrand, thanks for the links to those documents, interesting reading. I have had Museum of Retro Technology on my bookmarks for a couple of years, though. Excellent site, btw. A bit of mindboggling, what kind of calculations can be done with pantographs, rollers and gearing.

By: jayessell

jayessell — Mon, 03 Aug 2009 00:16:55 +0000

When I think of ‘War Tubas’ I think of this…

http://www.youtube.com/watch?v=Fa19ibXVnQU

Especially at 05:30 or so.

By: Firebrand38

Firebrand38 — Sun, 02 Aug 2009 23:43:10 +0000

Once again, in 1929 it’s all they had. After radar came into wide usage sound ranging against enemy artillery and aircraft went the way of the Dodo

Back in 1917 it was in it’s infancy as this 1917 manual reveals http://cgsc.leavenworth.army.m.....rcraft.pdf

http://www.dself.dsl.pipex.com.....ar/ear.htm
http://en.wikipedia.org/wiki/Sound_ranging

As to correcting for environment they really weren’t as stupid as all that as can be seen in this WW2 AA manual http://cgsc.leavenworth.army.m.....1_1940.pdf where they tell how to make corrections based things like temp and humidity.

By: Jari

Jari — Sun, 02 Aug 2009 22:29:28 +0000

As I served my national duty in AA corps as an radar engineer in eighties, this was a fashinating article. But microphones… As sounds are affected by wind and humidity, I’ll have my doubts about it’s accuracy even against zeppelins. Radar, of course is another thing. I’ll remember having fun with a Russian electromecanical servos, adders, substracters and other doodads, which comprised AA battery’s firing controller computer

By: Toronto

Toronto — Thu, 30 Jul 2009 03:54:18 +0000

I spent part of the 1970s living underneath a 3″/70 twin (it looked like this one: http://www.navweaps.com/Weapon.....he_pic.jpg)

It wasn’t the most pleasant place to be while it was firing at 90 rounds per minute. (Not that you’d be lounging in your bunk at those times.)

By: Firebrand38

Firebrand38 — Thu, 30 Jul 2009 02:23:05 +0000

The drawing was a case of artistic license coupled with ignorance.

The 3 inch gun looked like this http://www.antiaircraft.org/3inch.htm

By: GrumpyKiwi

GrumpyKiwi — Thu, 30 Jul 2009 02:08:58 +0000

Three inch is the calibre (or diameter of the barrel) of the weapon, not it’s size. (76mm). From the image supplied, I doubt it would fire at a high velocity, which is an important component of any AA weapon. And I would assume they would want the sound detectors to be seperated by a much larger margin.

By: Stephen

Stephen — Tue, 28 Jul 2009 12:35:29 +0000

Late in the Second World War a system like this was used as a defence against the German cruise missiles (the V-1). However, that automated gun was aimed by radar, not by sound tracking, which was of course far more reliable. They eventually got it up to an 82% success rate: see http://en.wikipedia.org/wiki/V.....ermeasures .

By: Eamonn

Eamonn — Mon, 27 Jul 2009 23:00:13 +0000

Good thing they worked just as advertised, otherwise London might have been bombed by the Nazis. Let the Hun tremble before the might of our invincible robot guns!

By: Firebrand38

Firebrand38 — Mon, 27 Jul 2009 19:37:24 +0000

In the August 1928 Coast Artillery Journal we find “A new development this year in the direction of increased accuracy is the device known as the torque amplifier, by the use of which
the battery is operated automatically from a distant station. The torque amplifiers are driven hy small electric motors and keep the gun set continuously at the proper elevation and azimuth. The importance of this development is in reducing the chance of personnel error. The pattern of the bursts is noticeably more uniform than the pattern made when firing with the follow-the-pointer system, and this is a better pattern than when sights are used.”

Looking at the Feb 1929 Coast Artillery Journal page 107 we find “Another development is the torque amplifier which permits the guns to be laid by the data computer without the aid of
traversing and elevating details at the guns. The type of sound locator now used is still the exponential horn, but corrections for sound lag and other conditions may now be applied automatically as is the case in gun fire. Furthermore, the data from the horns are received
at an instrument known as a comparator. Here the operator matches his pointer with the one actuated by the horn and so moves the light. This permits of’ distant operation of the searchlight, thus keeping the operator from being blinded by his own beam. Sound locators are to be carried in specially designed vehicles so that the whole unit, lights and locators, would be able to make from 30 to 35 miles an hour on good roads.”

Not quite the Robot Gun

By: Firebrand38

Firebrand38 — Mon, 27 Jul 2009 19:07:47 +0000

Not blimps. They couldn’t carry enough payload to make it worthwhile. Zeppelins on the other hand had participating in bombing raids over London during WW I and the first non-stop aircraft flight between European and American mainlands was the German ZR-3 (later the USS Los Angeles) which was a zeppelin being delivered to the US Navy in October 1924 as part of the war reparations.

But this is irrelevant. The first non-stop transatlantic flight had taken place in June 1919 when Alcock and Brown flew a modified bomber between Newfoundland and Ireland in 72 hours.

More to the point though, the first flat top aircraft carrier was converted in September of 1918. Prior to that the Japanese seaplane carrier Wakamiya conducted the world’s first naval-launched air raids on 5 September 1914 during the Siege of Tsingtao.

So yeah Thundercat, you could say that they had their concerns (but not about blimps).

By: JMyint

JMyint — Mon, 27 Jul 2009 19:06:15 +0000

I was curious. I knew the article was talking about predictors, the electromechanical computers used to aim AA artillery, but I guess he just didn’t come out and say it. Well I looked for Major W.P. Wilson and found that he was an inventor and engineer but not in the Ordinance Department but the Coastal Artillery Corps. The earliest mention of him I could find was a foot-note in the “Journal of the Franklin Institute”, July-December 1922, thanking him for the calculations require for the building of a Oscillograph Camera for the National Bureau of Standards. However and article in “The Coast Artillery Journal”, May 1923 states that Maj. Wilson submitted a sound plan for for an automatic ploting device and computing machine for anti-aircraft batteries that was similar to a device proposed by Maj. R.G. Groetzenburger of the Ordinance Department.

By: Thundercat

Thundercat — Mon, 27 Jul 2009 17:01:01 +0000

Thank God! Finally, something to save me from the horrors of blimp attacks!

By: Rick

Rick — Mon, 27 Jul 2009 14:29:25 +0000

If, as the article states, that’s supposed to be a three inch gun, then according to scale the one that is pictured is only about 20 inches long. And I love the way the author(s) state how invulnerable we’d be with these around our coasts!

Rick