Monday 27 July 2020

German Explosive Ordnance - Rockets (Part 19)







German Explosives





38-cm H.E. Rocket, Spin Stabilized


Overall Length: 56.68 inches
Diameter: 14.94 inches
Total Weight: 761 pounds
Propellant Weight: 88.5 pounds
Type of Filling: 50/50 Amatol, poured.
Weight of Filling: 270 pounds


Description: The H.E. body is of two-piece welded construction and is threaded internally at the after end to receive the motor body.  The booster pocket and fuze adapter is welded in position at the forward end.

The motor contains the propellant charge and igniters and is threaded internally to receive the venturi assembly.  A relay igniter charge, consisting of three bags of gunpowder, is located in the perforation in the central propellant grain.  The venturi assembly is drilled to form 32 jets at an angle of 14 degrees.  In the center of the assembly is located a threaded hole for the electric squib.  A rear spacer ring welded to the forward end of the venturi assembly acts as a grid and positions the outer row of propellant grains.


Remarks: The German designation for this round is "38 cm R. Sprgr. 4581"

The round is painted dark green overall, with an 0.8 inch white band painted around the center of gravity, and with black stenciling.

This round is notable among German rockets because of the steel splines inserted in the after end of the motor.  These splines engage the rifling of the projector liner and aid in imparting an initial rotation to the projectile.








R 100 BS Air-to-Air Rocket


General Description: The R 100 BS air-to-air incendiary rocket was originally designed as an uncontrolled rocket for attacking bomber formations from fighter aircraft.  This project was started in the latter part of July 1943.  During the latter part of 1944, however, it was decided to use the Oberon Gerat to control the bursting point of the rocket, thereby improving the chance of a strike from a negligible value to a probability of about 0.4.

Details of the rocket are somewhat sketchy but the salient features seem to be that the total weight was 100 kg, 180 cm in length, with a maximum diameter of 210 mm.  The propellant, consisting of 25 kg of normal rocket propellant, gave the projectile an impulse of 4,200 kg/sec with a burning time of 0.9 seconds.  The maximum range was estimated at 2,000 meters and the maximum velocity of 550-600 m/sec.

The warhead weighed 30 kg and contained 460 incendiary cylinders filled with thermite, each weighing 55 grams.  These cylinders were so arranged as to be stable during flight and fired forwards in a 60 degree cone.  They were intended to ignite the aircraft petrol tanks and had a lethal range of about 18 meters.  The incendiary cylinders had a velocity of 500 m/sec at ejection in addition to the velocity of the rocket.


Launching: Four of these projectiles were slung underneath the wings of a Me-262 and were launched electrically by rather complicated launching gear which comprised the following:

1. AZ 420 Kreiselvisir (Gyro Sight)

2. A radar range meter which is referred to as FUG 217 or 218.

3. A relative velocity meter known as the Oberon clock.

4. An Elfe, which apparently accepted signals from other components and carried out some sort of computation.

5. An altitude/angle computer.

6. A remote fuze setter.


It has been state that the rockets were launched electrically by means of the sight when the correct range (as measure automatically by the radar range-finder) was reached and not fired by the pilot.  These four projectiles could be launched either singly or in salvo, for which purpose a ripple firing mechanism with a 0.1-second interval was incorporated.  No control was applied after launching.



Remarks: Although this weapon had undergone satisfactory tests and was actually being produced, it never was, however, used operationally because of delays in the firing gear.



Next Time: Rockets (Part 20)


Source: German Explosive Ordnance Vol. 1: Bombs, Rockets, Grenades, Mines, Fuzes & Igniters

Tuesday 21 July 2020

German Explosive Ordnance - Rockets (Part 18)







German Explosives





28-cm H.E. Rocket, Spin Stabilized


Nature of Projectile: Multiple baseventing, spin-stabilized, pusher rocket.
Caliber: 280 mm

Filled Weight (complete round): 83 kilograms (183 pounds)
Overall Length (complete round): 1,190 mm (46.41 inches)

Nature of Fuze: Nose Percussion delay action
Nature of Filling: H.E.
Maximum Range: 2,339 yards.


Warhead
General Shape: Cylindrical canister with rounded ends, one of which receives the fuze and the other the tail unit.

Material: Sheet steel

Overall Length: 720 mm
Diameter: 280 mm
Wall Thickness: 1 mm
Weight of Filling: 36 kilograms
Filling: Amatol or TNT


Markings:
On Nose - 28 cm Wk. Spr.
On Body - 13 Mr. 5.6.42.G.


Method of Ignition: A separate electrical initiator enclosed in an aluminum tube and bakelite container, and which may be fired from a 4-volt battery, is screwed into the central drilling in the base.  For firing single rounds, initiators are provided, connected by 15 inches of two-strand insulated wire to a plug, and action is instantaneous on application of voltage.  For firing from Wurfgerat (four-frame stand), four initiators, externally similar in appearance, are provided, wired in series.  One only (tagged "0") is instantaneous and the remaining three (tagged "2", "4", and "6") include powder pellets so as to fire after intervals of 2, 4, and 6 seconds respectively.


Ignition Charge

Nature
Head: Compressed Gunpowder.
Base: Nitrocellulose in powder int he form of six-pointed, star-shaped flakes.

Weight
Head: (Unavailable)
Base: 10 grams

Container
Head: Flat, circular aluminum with open end towards propellant.
Base: Porous, rough-cloth bag.

Positioning
Head: In a pressed-steel housing supported by a flanged split ring.
Base: In center of grid.


Markings:
Head: None
Base: Wx. Man. St. P (2.25/23) dt1938/5 WO.7.842W.


Description: This is a spin-stabilized projectile consisting of a large warhead with a rocket motor of smaller diameter attached at the rear.  The projectile is electrically fired from the wooden crate in which it is carried or from a multiple launcher consisting of a number of frames of similar dimensions.


Warhead: The warhead is a thin steel shell sealed at the rear, where it has a flange threaded to take the rocket motor.  Two raised bearing surfaces on the body locate the projectile in the firing frame and also reduce lateral friction.  An adaptor in the nose of the warhead is threaded to take a nose percussion fuze and a gaine holder.


Rocket Motor: The rocket motor is in the form of a cylinder screwed into the rear of the warhead and closed at the rear by a plug in which are a number of offset venturi drillings.  The propellant, which consists of a single stick, is located at the forward end by a flanged metal spacing ring which also contains the ignition charge, and at the rear by a metal grid holding the rear ignition charge.  The base plug screws over the motor body and has a central drilling tapped to receive an adaptor for the electrical igniter.


Remarks: This rocket is designated the "28 cm Wfk. Sprg." 

The round is painted grey overall, with stencillings in black and white letters.








30-cm MEB H.E. Rocket, Spin Stabilized


Nature of Projectile: Multiple baseventing, spin-stabilized, pusher rocket.
Caliber: 300 mm

Overall Length (complete round): 48.44 inches
Overall Weight (complete round): 278 pounds

Nature of Fuze: Nose Percussion
Nature of Filling: Amatol
Maximum Range: 4,976 yards.


Warhead
General Shape: Elliptical with rounded forward end and truncated tail.

Material: Sheet steel

Overall Length: 29.5 inches
Maximum Diameter: 12.125 inches (across rib)
Wall Thickness: 0.109 inches
Diameter at Tail (External): 8.938 inches
Diameter at Tail (Internal): 8.625 inches
Diameter at Nose: 4.563 inches

Weights
Empty: 49 pounds 12 ounces
Weight of Filling: 98 pounds 6 ounces
Filling: 60/40 Amatol


Markings:
Stamped On Nose - 23.
Stamped in White approx. 4 inches below Fuze - 30 cm WK 42 Sp.
Stenciled on Rear Center: 13 Jg 29 9 42
Stamped on Lower End: 42, CKI.


Description: This projectile is similar in design to the 28- and 32-cm rockets, being spin-stabilized and consisting of a forward warhead to the rear of which is attached a rocket motor of smaller diameter.


Warhead: The warhead is constructed of two sections of sheet steel, a nose piece and a tail, the four sections being joined together by circumferential welds.  A single rib around the center of the projectile serves to reduce friction against the side of the launcher.  The nose piece is threaded to receive a nose fuze, Wgr. Z.50 and a gaine, and the tail internally threaded to screw onto the forward end of the rocket motor.  The H.E. filling consists of 96 pounds of amatol.


Rocket Motor: The rocket motor is of conventional design and consists basically of a cylindrical body and a base plug incorporating the venturi and igniter assemblies.  The body is machined internally and externally and is closed at the forward end, where it is threaded to screw on the tail of the warhead.  This end section is not flat but is slightly concave internally to permit a more even distribution of pressure.  The rear end of the body is threaded internally to receive the base plug which has 18 offset venturi drillings and a central drilling to take an electrical igniter.  The propellant, which consists of seven mono-perforate sticks, is located by two grids, one at each end of the motor body.  A celluloid tube containing a quickmatch train and plugged at each end by a gunpowder pellet, is located in the drilling in the central stick and transmits the flash from the igniter to the ignition charge at the forward end of the motor.



Remarks: The German designation for this round is "30 cm Wkf. 42 Spr."

The round is painted dark green overall, with black and white stencillings.





32-cm Incendiary Rocket, Spin Stabilized


Overall Length: 48.6 inches
Diameter: 13 inches
Total Weight: 174 pounds

Propellant Weight: 14.24 pounds
Length of Grain: 16 and ¼ inches
Diameter of Grain: 4 and  inches
Type of Filling: Kerosene mixture
Weight of Filling: 87.69 pounds


Description: This rocket consists of a large, bomb-shaped head, filled with an incendiary mixture and burster ignition tube, and a motor body to which the head is threaded.  The head has raised ridges fore and aft to provide bearing surfaces, and near the nose is a filling plug.  An adapter is threaded into the burster container, the base of the adapter containing a booster charge.  The burster contains two sets of one solid and one ring penthrite pellet.  Between the sets of pellets is located a magnesium filled ignition charge container, through the center of which passes a burster stick of penthrite.

The motor contains a single propellant grain with one central perforation and eight smaller perforations arranged at equal intervals around the central one.  Eight longitudinal grooves are formed along the exterior of the grain.  In each groove is fitted a tubular celluloid inhibitor.  Through the large central perforation is passed a length of quickmatch in a celluloid tube.  This serves to connect the head igniter with a primary ignition charge located in a cloth bag at the after end of the propellant grain.  The primary ignition charge and the propellant grain are supported by a metal grid attached to the venturi assembly.  The venturi assembly, drilled to form 26 jets at a 16 degree angle, is threaded to screw into the after end of the motor body.  A threaded hole in the base of the venturi assembly accommodates the electric igniter.


Remarks: The German designation for this round is "32 cm Wfk. M. Fl. 50"

This round is painted dark green overall.

Although recovered only with an incendiary filling, it is reported that this round may also contain a chemical charge.



Next Time: Rockets (Part 19)


Source: German Explosive Ordnance Vol. 1: Bombs, Rockets, Grenades, Mines, Fuzes & Igniters

Monday 13 July 2020

German Explosive Ordnance - Rockets (Part 17)







German Explosives





15.2-cm Anti-Aircraft Rocket, Fin Stabilized


Overall Length: 58.2 inches
Diameter: 7.09 inches
Total Weight: 150 pounds
Propellant Weight: 11 pounds 10 ounces
Length of Grain: 11.7 inches
Cable Length: 950 yards

Diameter:
Main Parachute: 11 feet
Pilot Parachute: 6 feet

Type of filling:
Upper H.E. Charge: RDX/Wax (95/5)
Lower H.E. Charge: RDX/Wax (95/5)

Weight of Filling:
Upper H.E. Charge: 2 pounds 6 ounces
Lower H.E. Charge: 1 pound 10 ounces


Description: This projectile is of the "aerial-wire-barrage" type and is used to project a steel cable into the air by means of a rocket.  One end of the cable is fixed to the ground and the other to a large support parachute and a smaller drag parachute.  When the cable has paid out, the parachutes are pulled from their housing.  The projectile is fin-stabilized and consists, from nose to tail, of the rocket motor, parachute housing, and upper and lower cable housing.


Rocket Motor: The rocket motor consists of a motor body, which is screwed into the parachute housing, and an ogival nosepiece containing a TNT destruction charge.  The motor body is a cylinder closed at the forward end and open at the rear.  There is no base plate, but the propellant gases are allowed to escape through four venturi drillings in the forward end of the parachute housing.  The propellant is a single, cylindrical, multiperforated stick and is ignited by means of an electrical base igniter, a train along the central drilling, and an ignition charge in a grid at the forward end.  Leads to the electrical igniter pass through one of the venturi drillings.  A delay fuze in the forward end of the motor body ignites the destruction charge in the nose piece.


Parachute Housing: The parachute housing, which is a cylinder closed at the forward end, serves not only to house the large main support parachute and the smaller drag parachute, but also as a base plug for the rocket motor.  The forward end has four venturi drilled obliquely in the sides of the body.

At the forward end of the parachute housing is a TNT destruction charge enclosed in asbestos.  Although this has a primer, there is no means of initiation; it is assumed, therefore, that this charge is set off by sympathetic detonation from the charge in the nose of the projectile.  Below this destruction charge is the main parachute wrapped in asbestos and below it the small drag parachute.


Cable Housing: The cable housing is constructed in two separate halves.  The upper half is attached to the base of the parachute housing and accompanies the projectile on its flight.  The lower portion of the housing has a flanged base, which fits into the mounting and remains on the ground.  The finned tail unit is spot welded to the upper half and fits over the lower portion.  This maintains the projectile in position until it is fired.  A slot is provided in two of the fins through which a wire is passed, holding the lower section in position; this wire should be removed before firing.

A continuous length of approximately 950 yards of 1/8-inch steel cable is coiled in equal lengths inside each portion of the cable housing.  The end of the cable in the upper portion is attached to the parachute, and the other end passes through a hole in the bottom of the lower portion and terminates in an eyebolt secured to the launching frame.


Operation: The actual barrage consists of the support parachute, drag parachute, and cable.  The projectile is evidently launched from some kind of frame (no specimen of this had yet been recovered, to which the lower portion of the cable housing is fixed.  When the propellant charge is ignited, the projectile climbs until, theoretically, the whole of the cable has paid out.  The drag parachute and the main support parachute are then withdrawn from the parachute housing and the main unit continues on its course, leaving the cable suspended in the air.

When the propellant burns out, the destruction charge in the nose piece, actuated by the delay fuze, destroys the rocket motor and parachute housing.  It is presumed that the charge in the forward end of the parachute housing is at this point set off by sympathetic detonation to assist in this destruction.









20-cm Anti-Aircraft Rocket, Fin Stabilized


Overall Length: 64.3 inches
Diameter: 8 inches
Total Weight: 159 pounds 3 ounces
Propellant Weight: 11 pounds 9.5 ounces


Description: This rocket is similar in design and operation to the 15.2-cm anti-aircraft rocket but is much cruder in construction.  The round consists of a rocket motor at the forward end, a middle compartment containing the parachute and the cable housing surrounded by the fin sleeve.



Operation: On firing, the cable housing remains on the ground, and the rest of the assembly is projected into the air, uncoiling the cable from its housing.  When the cable is completely unspooled, the parachute is withdrawn through the fin sleeve.  The separation of parachute and motor operates a pull igniter, which initiates a demolition charge contained in a central tube in the motor.



Remarks: The round is painted dark green overall.





21-cm H.E. Anti-Aircraft Rocket, Spin Stabilized


Overall Length: 49.2 inches
Diameter: 8.27 inches
Total Weight: 241.3 pounds

Propellant Weight: 39.5 pounds
Length of Grain: 21.67 inches
Diameter of Grain: 2.46 inches
Type of Filling: Amatol 40/60
Weight of Filling: 22.4 pounds


Description: This is a streamlined aircraft rocket projectile, consisting of an H.E. shell, externally threaded at the base to screw into the rocket motor and at the nose to receive a ballistic cap.  A booster container is threaded into the nose of the shell and receives the nose fuze.  A wooden actuating rod separates the fuze from the tip of the ballistic cap.

The motor body is a cylindrical steel body machined externally to form fore and aft bourrelets.  A venturi assembly, drilled to form 22 jets, threads into the base of the motor.  The jets are inclined at an angle of 16 degrees to impart a rotary motion to the rocket in flight.  An electric squib is threaded into the center of the venturi assembly.  The propellant charge consists of 7 single-perforated grains supported by a metal grid at the after end.  A ring-shaped black powder igniter is placed at the base of the charge and a second igniter is located at the forward end of the charge.  These two ignition charges are connected by a length of quickmatch in a celluloid tube, which passes through the perforation of the central propellant grain.


Remarks: The German designation for this round is "21 cm Wgr. 42 Spr."

This round is painted green overall.




Next Time: Rockets (Part 18)


Source: German Explosive Ordnance Vol. 1: Bombs, Rockets, Grenades, Mines, Fuzes & Igniters

Monday 6 July 2020

German Explosive Ordnance - Rockets (Part 16)







German Explosives





8.8-cm H.E. Hollow Charge Rocket, Fin Stabilized


Nature of Projectile: Multiple-venting, non-rotating, fin-stabilized pusher motor.
Caliber: 8.87 cm

Overall Length (Complete round): 19.4 inches
Total Weight (Complete round): 5 pounds, 13.5 ounces

Nature of Fuze: Instantaneous nose percussion
Nature of Filling: Cyclotol


H.E. Head
General Shape: Cylindrical main body; truncated, conical impact cap and rear section

Overall Length: 10.47 inches
Diameter of Bearing Surface: 3.494 inches
Depth of Cavity Liner: 3.67 inches

Main Body Wall Thickness: 0.045 inches
Impact Cap Wall Thickness: 0.09 inches
Cavity Liner Wall Thickness: 0.06 inches

Forward Diameter, Impact Cap: 1.356 inches

Weight (Empty): 4 pounds 0.75 ounces
Weight (Filling): 1 pound 7.14 ounces


Markings:
Cylindrical Portion of Body:
Stenciled in Purple - WaA 424
Stenciled in Black - Tpn 2.3 44D LM 4312

Rear Portion of Body:
Stenciled in White - 43 fcc 47



Description: This projectile is fired from the mobile anti-tank rocket launcher 8.8cm Raketenwerfer and is similar in appearance to the 8.8cm Raketen Panzerbuchse Granate 4322.  The projectile, which is fin-stabilized, consists basically of an H.E. head, a motor tube, and a tail-fin assembly.


H.E. Head: The head of the projectile consists of the body containing the cyclotol hollow-charge located by a cavity liner and an impact cap.  The impact cap is flanged at the read end to bear against the cavity liner and is fitted at the forward end with an adapter, threaded to receive either of two nose percussion fuzes, the A.Z. 5095 or the A.Z. 5095/1.

Two pressed flanges at the forward end of the body secure the impact cap and the cavity liner.  The rear end of the body is conical in shape and fits over a tail adapter which forms the junction with the motor tube.  A reinforcing sleeve is pressed into position over the cylindrical portion of the body and provides the forward bearing surface of the projectile.

At the lower end of the cavity liner is a flash tube below which is located the gaine; this consists of an aluminum cup containing a charge of PETN and wax and a detonator.  The gaine is separated from the motor tube by a wooden plug which acts as a buffer and which also provides the necessary thermal insulation between the motor and the gaine.


Motor Tube: The forward end of the motor tube is sealed and threaded to screw into the tail adapter.  The rear is screwed into the venturi block.

The propellant consists of a single stick with 14 small longitudinal perforations and a single axial drilling of larger diameter.  Three lands around the outside of the stick keep the propellant from touching the inside of the tube and ensure an external burning surface.  Two grids, one at each end, are used to support the propellant; each grid is a triangular metal platform on three legs.  At the rear there is a wire mesh between the grid and the propellant to prevent any unburnt particles from blocking the venturi drillings.

Between the grid and the propellant at the forward end is an ignition charge mounted so that it is free to burn on both surfaces.  A celluloid tube, containing a thin strip of what appears to be nitrocellulose powder, is located in the axial drilling of the propellant; both ends of the tube are capped with a block of black powder.  This train serves to transmit the flash from the primer to the ignition charge at the forward end of the motor tube.


Tail-Fin Assembly: The tail-fin assembly consists of a venturi block, stabilizing fins, obturator, and percussion igniter.

The venturi block, which is screwed over the end of the motor tube, has six venturi drillings parallel to the axis of the projectile.  These are each formed by two drillings of different diameter; instead of taper there is a sudden step from the smaller to the larger diameter.  The block is drilled and tapped in the center to receive the firing-pin adapter.  A collar on the rear of the firing-pin adapter holds the obturator in position around the rear of the fin assembly.  A percussion cap is mounted in the forward end of the firing-pin adapter, immediately in rear of the quickmatch train.  The adapter is machined down to a separation point near the rear end; when the projectile is fired, the adapter severs, and the rear portion remains in the breech together with the obturator.

The six stabilizing fins are mounted in three pairs around the venturi block and are strengthened by a sleeve fitted around the fins and under the forward lip of the obturator.



Remarks: The German designation for this round is "8.8 cm R. Pz. B. Gr."

This same round, modified for percussion firing, is used in a single tube, two-wheel launcher, the "8.8cm Raketenwerfer 43"









15-cm H.E. Rocket, Spin Stabilized


Overall Length: 38.55 inches
Diameter: 6.22 inches
Total Weight: 70 pounds

Propellant Weight: 14 pounds
Type of Filling: TNT
Weight of Filling: 4.5 pounds


Description: This rocket resembles an elongated gun projectile with a bulbous nose cap.  The round consists of a forward motor body containing the seven single-perforated propellant grains and the after H.E. container.  An enlarged diameter ogival ballistic cap is threaded to the forward end of the motor, and a venturi assembly with 26 drilled jets threads over the base of the motor.  The venturi assembly also is threaded externally at its after end to receive the machined steel bursting charge container.  An H.E. charge in a fiber container is placed in the steel shell case, separated from the base of the motor by an iron spacer to provide an insulating air void between the H.E. and propellant charges.  A booster adapter, containing the booster charge and threaded to receive the base fuze, screws into the base of the H.E. shell.

The propellant grains are supported fore and aft on a pair of metal grids.  A black powder igniter charge is placed over the rear grid, and a second black powder charge is contained in an aluminum holder between the head of the motor and the forward grid.  The two charges are connected by a black powder filled cellulose tube, which passes through the perforation of the central grain.  An electric igniter is fitted into 1 of the 26 jets.



Remarks: This round is designated "15-cm Wgr. 41 Spr."









15-cm Smoke and Chemical Rocket, Spin Stabilized


Overall Length: 40.16 inches
Diameter: 6.22 inches
Total Weight: 79 pounds

Propellant Weight: 14 pounds
Type of Filling: Smoke Composition
Weight of Filling: 8.5 pounds


Description: Except for the shell after body, this rocket is identical to the 15-cm H.E. rocket.  The motor arrangement is identical to the latter, and the shell similarly attached to the motor.  The shell for the smoke rocket is 4.5 inches longer than that for the H.E. round and is somewhat differently constructed.  The shell consists of a thin-walled steel cylinder with a long burster charge container threaded into the after end.  This container holds 3.05 pounds of picric acid.  The container is threaded to receive a base fuze and a short exploder.  The smoke composition is located between the shell body and the outer wall of the burster container.



Remarks: The German designation for this round is "15-cm Wgr. 41 Nb."

This round may also be employed as a chemical shell.  When so used, the German designation is "15-cm Wgr. 41 Grunring"




Next Time: Rockets (Part 17)


Source: German Explosive Ordnance Vol. 1: Bombs, Rockets, Grenades, Mines, Fuzes & Igniters