SBS Model Toldi Sets

SBS Model has released three new 1/35th-scale resin and photoetch sets for the Hobbyboss Toldi I kit — 35014: 1/35 Toldi Tools and Equipment (Toldi I, Toldi II, Toldi III) for Hobbyboss Kit; 35015: 1/35 Toldi I (B20) corrected turret (without barrel) for Hobbyboss Kit; and 35016: 1/35 Toldi I (B20) corrected turret (with metal barrel) for Hobbyboss Kit.

toldi-SBS35014 toldi-SBS35015 toldi-SBS35016-1

 

A-26 Upper Turret Angles

Diagram of the upper turret fire interruption angles for the A-26, from: Pilot’s Handbook for Army Models A-26B and A-26C Airplanes, AN 01-40AJ-1, August 1945, revised January 1946.

a26-upper-turret-guns

This illustration shows the gunfire intercepting areas and the margins of interruption (approximately) and indicates the limits of gunfire from the upper turret for efficient use of the guns by flight personnel.

 

Naval Twin 5-Inch Turret

Details of the twin mount 5-inch/38 cal. naval gun from Naval Ordnance and Gunnery, NAVPERS 16116, Bureau of Naval Personnel, Training Division, May 1944.)

Enclosed twin mount and handling room; 5-inch/38 cal. gun.

Enclosed twin mount and handling room; 5-inch/38 cal. gun.

Twin mount plan view; 5-inch/38 cal. gun.

Twin mount plan view; 5-inch/38 cal. gun.

 

5-Inch Naval Gun Turret

Cutaway drawing of the Mark 12 5″/38 caliber U.S. naval gun. (Source: Naval Ordnance and Gunnery, NAVPERS 16116, Bureau of Naval Personnel, Training Division, May 1944.)


 

Machine Gun Turrets

Introduction to aircraft machine gun turrets from the WWII manual Index of Aeronautical Equipment with Navy and British Equivalents: Volume 5, Armament, March 1944.

MACHINE GUN TURRETS
(LOCAL CONTROL TYPES)

The primary function of a machine gun turret is to provide an automatic means for a gunner to track a target and operate the guns. All turrets consist of an enclosure, a turret control system, and means of mounting, sighting, feeding, and firing the guns.

Upper Turret

The locally-controlled turret is a rotatable structure in the form of a ball, dome, or rounded cylinder, in which one or more machine guns are mounted. The guns are sighted, controlled, and fired by a gunner within, above, or below the turret, depending upon its type and location in the airplane.

Turrets are designated according to their installation in the airplane, i.e.: upper turrets (on the upper deck), lower or belly turrets (under the fuselage), tail turrets, and nose turrets.

Upper turrets are non-retractable and have dome-like, transparent enclosures of plexiglas and metal under which the gunner sits or stands. The guns may be rotated through 360 degrees horizontally, through 90 degrees in elevation, or any simultaneous combination of the two movements.

Lower, or belly turrets can be either retractable or non-retractable. They may be spherical, with the gunner seated inside; or hemispherical, with the gunner kneeling inside the airplane above the turret. The enclosures are usually of metal and plexiglas. The guns may be rotated through 360 degrees horizontally, through 90 degrees in depression, or any simultaneous combination of the two movements.

Lower Gun Turret and Ball Turret

Tail turrets are not retractable. The cylindrically-shaped enclosure includes steel armor plate protection, a cover of transparent plexiglas, and, in some installations, flat panes of bullet-proof glass. The gunner is seated completely inside the structure and controls the turret to move the guns through approximately 180 degrees horizontally, 90 degrees upward, and 90 degrees downward.

Continue reading Machine Gun Turrets

How to Jettison a PB4Y Ball Turret

Procedure to jettison the nose ball turret in the PB4Y from Naval Aviation News, August 1944.

How to Jettison a Turret
PB4Y Gets Back Safe from Saipan

A Navy photographic plane came back from a mission over Saipan recently after battling through 15 attacking Zekes which swarmed in when one of the PB4Y’s engines cut out. One of the main reasons it got back, however, was that the crew had worked out carefully the procedure for lightening the load by jettisoning the ball turret.

The Zekes attacked the plane 30 miles from Tinian on the trip home and continued the fight for 70 miles. Although the point at which the engine cut out was 1,000 miles from its home base, the plane made the grade because of skillful piloting and some active tossing-overboard of all movable gear. Major items included all guns and ammunition, all cameras, armor plating from turrets, all radio equipment except one set–and the ball turret.

Procedure for jettisoning the turret had been worked out carefully in squadron drills ahead of time. By following this procedure, the crew got rid of it in 20 minutes, going through the following steps:

1. Turn off the electric power switch on the overhead and cut all electric wiring.

2. With the elevation handle, point guns straight down.

3. Disengage azimuth power clutch.

4. Disconnect oxygen system and remove oxygen bottle.

5. Remove the azimuth gear box by taking off the four holding nuts.

6. Remove the eight vertical bearings which are held in place by two bolts. They bear on the scarf ring.

7. Place the turret in the fore and aft position.

8. Lower the turret and the scarf ring together. This prevents the turret from swaying in the slipstream.

9. Using the waist-gunners’ safety belts, secure the turret so it will not drop when trunnion nuts are removed. The belts should be secured between the turret A frame and the turret retracting piston.

10. Remove the six nuts that secure the turret trunnion housing to the turret retracting assembly.

11. All hands stand clear and two men cut the two safety belts at the same time. It is suggested that nuts and bolts to be removed be painted same color other than the color of the turret, so that if an emergency arises they can be spotted immediately.

Before the turret and other gear were jettisoned, the plane lost altitude on auto-lean and gradually descended from 20,000 to 6,000 ft. As soon as the turret was dropped the plane was able to maintain its altitude in auto-lean.

 

Thanks to the Power Turret… The Bomber Fights Back

The importance of the modern power gun turret to U.S. bombers in WW2 from Aircrewman’s Gunnery Manual, Aviation Training Division, Office of the Chief of Naval Operations, U.S. Navy, 1944

Thanks to the Turret…  THE BOMBER FIGHTS BACK

  • Without the men who invented the turret, today’s great bombing missions would be impossible. For without turrets, the bomber would be almost as helpless over enemy territory as an ordinary transport plane without a single gun.
     
  • No one knows exactly who should get credit for inventing the modern turret. The first crude models came out in the 1920’s. One was a circular mount, illustrated on this page, which the United States developed to put a little flexibility into bomber guns. The Russians tried a movable platform, cranked by hand, in which the gunner sat right out in the open, fighting the slipstream as well as the enemy.
     
  • Early Aircraft Gun Turret

  • The modern power turret–driven by electricity and mounted inside the bomber–was developed after many experiments in the 1930’s and proved its worth in action in the second year of World War II. Its effect on air strategy was spectacular. At last the bomber–heavier and slower than the fighter plane–could really fight back.
     
  • For turrets–little blisters of plexiglas or safety glass, bristling with caliber .50s, swinging around to meet enemy fighters no matter where they come from–enable the bomber to match the enemy slug for slug in an air battle.
     
  • Approach an American bomber today, from any angle, and you will see a turret whose guns could be turned toward you in an instant.
     
  • The top turret swings in a full circle; its guns move up and down from straight out to nearly straight up; it protects the whole top of the plane.
     
  • Continue reading Thanks to the Power Turret… The Bomber Fights Back

Erco Ball Turret

Illustrations and performance details of the Erco 250SH Ball Turret mounted in the PB4Y Privateer from Aircrewman’s Gunnery Manual, Aviation Training Division, Office of the Chief of Naval Operations, U.S. Navy, 1944.

Erco Ball Turret

Erco Ball Turret
ERCO 250SH-2, 2A or 3

The Erco Ball Turret is the bow installation in the Navy PB4Y-1 and PB4Y-2 airplanes. It serves a double purpose in taking care of any bow attacks on the Liberator besides being used for strafing, in anti-submarine warfare. Inasmuch as this turret is of the ball type, the gunner moves with his guns and sight in elevation and azimuth as he moves his control handles. It is a relative of the Martin 250SH Bow Turret of the PBM-3 airplanes and has many points of similarity in design and action.

There are several models which for the most part are the same—the Erco 250SH-2 or 2A used in the bow position of the PB4Y-1 airplane and the Erco 250SH-3 used in PB4Y-2 airplane.

Erco Ball Turret -- PB4Y Privateer Nose Turret
Facts and Figures

POWER: The Erco 250SH operates hydraulically on pressure built up by a hydraulic pump driven by a constant speed electric motor.

SIGHT: Its sight is the standard Navy Mk 9 reflector sight, fully described in the introduction of this section.

ELEVATION: From the horizontal position the turret ball, and consequently the guns, may be depressed a maximum of 70° and elevated a maximum of 85°.

AZIMUTH: This type of turret is capable of revolving 360° in azimuth, but for the installation in the bow of the PB4Y-1 or PB4Y-2 airplanes, its motion is restricted to 80° either side of the center line of the plane.

ARMOR: The armor plate of the turret consists of three parts to protect the gunner from enemy fire and flak: (1) 1½” laminated bullet proof glass to protect his face. (2) ½” armor plate in front to protect the gunner’s body, no matter where his guns are pointed. (3) ¼” armor plate bolted to the floor to protect his feet.

STOWING: The stowing position is 0° azimuth and 0° elevation, guns pointing straight forward.

 

Bendix Chin Turret

Bendix manual on the Operation and Maintenance of the Bendix Chin Turret for the B-17 Flying Fortress:


Operation of the Bendix Chin Turret

GENERAL SPECIFICATIONS

Armament
Two Caliber .50 M-2 machine guns.
Ammunition Capacity 450 rounds per gun.

Speed of Turret
Slow speed (tracking) ¼° per second to 12° per second.
High speed (slewing, with high speed button depressed) ¼° per second to 33° per second.

Weights
Turret Complete (no guns or ammunition) 438 lbs.
Ammunition 33 lbs. per 100 rounds.
Guns 65 lbs. each.

Gear Drive
Speed Reducer ratio 25-1.
Azimuth gear ratio 50-1.
Elevation gear ratio 42-1.
Azimuth gear train reduction 1250-1.
Elevation gear train reduction 1050-1.

Electrical Requirements
24 Volt D.C.
Peak starting current motor amplidynes 1280 amps.
Maximum current draw running full load 92 amps.
Maximum current draw running no load 40 amps.

Drawing of B-17 Flying Fortress

GENERAL DESCRIPTION
BENDIX CHIN TURRET

The Bendix Chin Turret Model “D” is an electrically driven power turret, mounting two caliber, .50 M-2 Machine Guns, equipped with recoil absorbing mechanism, firing solenoids, and manual gun chargers.

The turret is designed to be mounted in the Bombardier’s Compartment and to be operated by the Bombardier to protect the forward approaches to the ship. The guns rotate 172° in azimuth (86° to the left and to the right of forward) and swing from 26° above horizontal to 46° below horizontal. Switch limits are adjustable. The turret is mounted at floor level in the Bombardier’s Compartment. The guns extend below the fuselage at the nose of the ship. The lower assembly, with the exception of the gun barrels which protrude through covered slots, is enclosed in an aluminum, movable housing to minimize wind resistance. Plexiglass windshields seal the space at the floor of the ship around the turret.

B-17 Bomber Chin Turret

Continue reading Bendix Chin Turret

Erco Tear Drop Turret

Illustrations and performance details of the Erco 250TH Tear Drop Turrets mounted in the PB4Y-2 Privateer from Aircrewman’s Gunnery Manual, Aviation Training Division, Office of the Chief of Naval Operations, U.S. Navy, 1944.

Erco Tear Drop Gun Turret - Erco 250th - U.S. Navy Consolidated PB4Y-2 Privateer

ERCO TEAR DROP TURRET
ERCO 250TH-1 AND 2

The Erco 250TH Turrets have the approximate shape of a tear drop. They are installed in the waist positions on either side of the PB4Y-2 airplane—the Erco 250TH-1 on the starboard side and the Erco 250TH-2 on the port side. With their wide cone of fire they protect the plane from beam or belly attacks, besides offering a considerable area of protection from above. In operation they are somewhat similar to a ball type turret inasmuch as the gunner moves with his guns and sight in the direction he moves his control handles.

Erco Teardrop Gun Turrets Navy Consolidated PB4Y-2 Privateer

Facts and Figures

POWER: The Erco Tear Drop operates hydraulically on pressure built up by a hydraulic pump driven by a constant speed electric motor.

SIGHT: Its sight is a standard Navy Mk 9 reflector sight fully described in the introduction to this section.

ELEVATION: Both turrets can raise their guns 55° above horizontal in elevation and depress them 95° below horizontal.

AZIMUTH: In azimuth, the Erco Tear Drop turret allows the guns a movement of 135°, 55° towards the bow from the beam and 80° towards the tail of the airplane from the beam.

ARMOR: The armor plate in the turret protects the gunner from fire in any direction he turns his guns. It consists of three groups: (1) 1 1/2″ thick bullet-proof glass in front of his face, (2) 5/16″ armor plate in front of his body, and (3) 5/16″ armor plate under his feet.

STOWING: The stowing position is 0° elevation with guns pointed in the extreme aft position in azimuth (80° aft of the beam).