Questions on Italian AA fire control

[sdae102]

Italian Battleship AA fire control questions


Hello all:

I am seeking information on the control of Italian heavy (130mm) medium (100mm) AA gun control on the Duilio and Littorio class ships.

Question 1: Was there a separate (from main/secondary armament control) a centralized AA plot/control facility. Or were the AA guns controlled directly from their respective directors?

Question 2: Does anyone have detailed information on the director designations of all BB calibers of fire control equipment for the Italian ships? And possibly have, or know of the location of in a reference book of detailed photos and/or line drawings of the Italian directors?


Question 3: I am also seeking line drawings of the aircraft catapults fitted to the Littorio class ships.

Of you have or know of the above information please contact me a sdae103@yahoo.com. Any help would be greatly appreciated and fully credited and acknowledged 'in print in' my upcoming book release on Italian Battleships.

Thank you all in advance

Regards

Wayne

[USS ALASKA]

Sir, a person you might wish to contact is http://bobhenneman.info/forum/profile.p ... file&u=109. He seems very knowledgeable on things of this nature.

[tommy303]

You might want to check out Campbell's Naval Weapons.

[Lutscha]

A copy of one of Antonio Bonomi`s posts on the Marinearchiv:
http://forum-marinearchiv.de/smf/index. ... ml#msg9699

Ciao all,

well later you will see the pics related to this explanation when thru Thorten we will be able to post them.

Vittorio Veneto class Fire Controls

The fire direction system on the Vittorio Veneto class was initially installed on the rebuilt Duilio and Doria battleships.

It was a set of very modern equipment for the period and unless an addition of one radio-tele-meter ( now better known as R.A.D.A.R. ) they were never changed.

For the data elaboration they were all referring to the ( Centrale Tiro ) central fire direction system installed on the second aisle under the protection deck, after the barbette of turret number 1, basically below the main tower.

This data elaboration system was based on : a ‘ Centrale Automatica San Giorgio ‘ ( name of the system ) for big units ; with 4 additional subsystems ( Mobilone a 4 smistamenti ) ; an energy distribution system ( power control ), one inclination control ( Mediatore Beta Inclinometro ) ; one control of telemetric distances evaluations ( Mediatore distanze Telemetriche ) ; of a control panel for turrets fire ( Quadro Comando fuoco torri ) ; of a recording system for the fire executed ( Registratore Dati di Tiro ) ; of a receiver of the rudder angle ( Ricevitore angolo di barra ) ; of a receiver of the ship speed ( Ricevitore Velocita’ propria dal solcometro ); of a receiver of the bearing from the A.P.C. ( Central Fire Direction Rangefinder ); of a Gimetro ( variation of the target bearing evaluation system ).

On of the main tower ( Torrione ), around 30 meters from the waterline, there was the First Artillery Officer fire direction station ( Coffa del 1° D.T. Direttore Tiro ) on a cylinder with 2 lateral area for the spotters ( on the Roma going all around the cylinder ).
From this station the A.P.G ( Apparecchiatura Punteria Generale ) central targeting system type San Giorgio which allowed to monitor the target and allowed the fire with buttons that could fire the main turrets.

This cylinder for the first artillery officer ( 1° D.T. cylinder ) was directly connected with the cylinder down below, which contained Central Artillery Room ( Centrale Servizio Artiglierie ), with the central fire system ( Centrale Tiro Principale ) on the superior rangefinder cylinder / turret ( Torretta Telemetrica Anulare Superiore ).
This big rotating cylinder was placed under the 1° DT and contained 2 big rangefinders of 7,2 meters type San Giorgio ( one stereoscopic and one at coincidence ) used to measure the target distance.

Moving down below there was the inferior rangefinder cylinder / turret ( Torretta Telemetrica Anulare Inferiore ) a bit smaller than the one above because only had 1 rangefinder still model type San Giorgio of 7,20 meters called ‘ tactical rangefinder ‘ used to evaluate various enemy distances as well as better target findings, etc etc , without any interference with the other 2 above rangefinders used to fire the guns.

In case of ‘ out of action ‘ of the 1° D.T. ( First Artillery control station ) it was possible to pass the control to the 2° D.T. ( Second Artillery Officer control Station ) which was located down below the ‘ tactical rangefinder ‘ cylinder and above the Admiral armoured room cylinder.
This second artillery control station was equipped with an A.P.C. ( Apparecchiatura Punteria Centrale ) which was having their lenses on the of the room coming out in front of the main tower.

Additionally on each main gun turret there was a Central System reduced model type Galilei with a big rangefinder model type Duplex-San Giorgio of 12 meters which allowed each turret to fire on their own independently.

Summarizing the fire could have managed with several different methods :

a) All the turrets under the 1° D.T. control with A.P.G. central or turrets 2 or 3 reduced centrals.

b) All the turrets under the 2° D.T. Control with A.P.G. central or turrets 2or 3 reduced centrals.

c) Turrets 1 and 2 directed by 2° D.T. with A.P.G. central or turret 2 reduced central, while turret 3 with 1° D.T. with A.P.G. Central or turret 3 reduced.

d) All turrets directed by turret 2 Fire Director managing the central A.P.G or the reduced central of turret 2 itself.

As you can see many different options including at the end all the options of use by each singular turret itself or managing another one as slave.

For the first time it was thought to fire also in the darkness so for this purpose 2 dedicated systems were located one each side of the command platform that can manage the turrets fire independently. On reality they were never used due to the lack of a real system to evaluate distances on the darkness.

The only radar ever installed on the Vittorio Veneto class was in fact installed on late 1943 ( summer ) just 2 months before the ships sailed to malta in execution of the armistice signed on September 9th, 1943.
Even if it was Guglielmo Marconi on June 20th, 1922 to start developing that theory, Regia Marina never got a radar till summer of 1943 when a radar ( radiotelemetro ) model ‘GUFO’ built by Marinelettro of Livorno was installed on of the main tower ( torrione ) with a 360° degrees rotating angle.

The secondary 152 mm guns fire direction was based on the side from were the enemy was located.
In fact between the 2 funnels there was on each side the rangefinder stations equipped with a rangefinder ( stereo-telemetro ) Model type San Giorgio of 5 meters with related A.P.G. central fire direction system and all the other instruments.
The 2 lateral turrets were connected with 2 central fire control station located under the protection deck on the 2 sides of main turret 2.
The 4 triple 152 mm turrets were also singularly equipped with a 6,3 meter rangefinder model type San Giorgio and a reduced fire control station model type R.M. 4.

Than there were the Anti-Aircraft rangefinders of 3 meters placed aside of the main tower with their own dedicated A.P.G. ( central control fire system ).

Finally there was under the mainmast a spare 3 meters rangefinder.

Hope my explanation is satisfactory, if you need more details just let me know.

Ciao Antonio

[sdae102]

Antonio

Thank you for your detailed post...It is much appreciated and if you are unable to post the photos to the forum please email them to me at sda103@yahoo.com.....and please include your last name for credit listing in my upcoming book on Italian BB's......Thx again wayne

[sdae102]

Antonio:

I am also seeking confirmation of the Search Radars mounted on Duilio and Doria postwar the one atop the foremast is I believe a USN SG4 set, and the air search dipole antennas mounted lower on the foremast and on the aft tower....I believe they are UK type 281B's, but 1951-52 Jane's states they are US Army sets, although I was unable to find any reference to a US Army set that remotely resembled them....any knowledge on these? Thx Wayne