GERMAN HEAVY TRANSPORT TRAILER

The following information concerning the German heavy transport trailer was obtained in a recent examination of one of the vehicles by our own Ordnance officers.

The trailer has an overall length of 38 feet 10 1/2 inches, wheelbase from front bogie to rear bogie of 28 feet 8 inches; its total weight unloaded is 31,810 pounds and its load-carrying capacity is approximately 35 tons.

The trailer consists of front and rear bogies with a load platform suspended between them. This platform is constructed of two main I beams and two secondary I beams parallel to each other. The primary I beams extend past the platform in front and rear and constitute the only means of attaching the platform to the bogies. This is done by the use of four heavy fingers, two per bogie, that fit in rectangular slots in each of the primary I beams. This assembly is secured by large pins inserted through the slots and fingers. The front bogie attachment to the load platform is semi-permanent while the rear bogie attachment is removable.

a. Specifications

Front bogie section weight 9,560 lbs Platform 10,850 lbs Rear bogie section weight 11,400 lbs Ground clearance 1 ft 10 in Ground to platform top 2 ft 3 in Width from center of tires 8 ft 3 1/2 in Platform size 19 ft 1 in x 9 ft 10 1/2 in Rear bogie section length 9 ft 7 in Front bogie section length 9 ft 9 in Drawbar length 5 ft 4 in Turning radius (using rear steering in addition to drawbar) 58 ft

There are eight wheels (singles) with size 13.50 x 20 tires. In addition to these wheels for the running gear there are two spares (same size). All tires are 16-ply and hold 114 lbs per square inch of air.

b. Suspension

(1) Leaf-type springs, one for each wheel, eight in all, having 11 leaves each spring.

(2) Thickness of spring leaves, 3/8-inch.

(3) Length of spring overall, 4 feet.

GERMAN HEAVY TRANSPORT TRAILER

c. Maker and Markings

In the trailer which was examined there was a part of an instruction manual, the text of which indicated that the vehicle was probably built by the Waggon Maschinen Fabrik at Bautzen, Germany. The figure of a tiger, stenciled on the trailer, may signify that it was attached to a unit serving the German heavy tank Pz Kw 6, called the "Tiger".

(1) Markings on the rear of the trailer were:

Vorsicht beim Überholen (Be careful when passing)

Anhängerbreite 3 Meter (Width 3 meters)

Heben (Lifting) Senken (Lowering)

Schnellgang (Fast gear) Normalgang (Normal gear)

Markings on the rear of the fenders were:

Beim Senken Kupplungskopf, 2 Kabelstecker & 2

Stossdämpfergestängebolzen Lösen (Disconnect coupling

head, 2 cable connections, & 2 shock absorber bolts when

lowering).

(2) Markings on the rear of left cab were:

Vor jedem Senken oder Heben der Ladebrücke ist die Öl pumpe

zu Betätigen & die Zahnflanken des Getriebes im Windenkasten

Einzufetten (Each time before lowering or raising load platform,

lubricate with oil pump and grease gears in winch box.)

(3) Below the above instruction plate were these markings:

Druckschmierung (Pressure lubrication)

(4) Markings on the rear of the front truck were:

Stossdämpfergestängebolzen im Gelände lösen (Disconnect

shock absorber bolts in rough terrain.)

d. Loading

Trailer must first be positioned so that if the vehicle to be loaded is dead, the winch cable can be used to tow the vehicle on the trailer platform.

Large pins securing the two fingers of the rear bogie section in the rectangular slots of the primary I beam must be turned past their catches and removed.

Lower the rear of the trailer platform by means of the two hand-driven winches which are located one on each side of the rear bogie section. These winches must be turned in the direction marked Senken . When the rear end of the platform is resting on the ground, pressure is taken off the tongs holding the platform and they can be released.

When the rear bogie section is free of the trailer the section must be pushed out of the path of the vehicle to be loaded.

After the vehicle to be loaded is pulled on the platform by means of the winch of the prime mover, the rear bogie section is repositioned over the rear of the trailer platform, the lifting tongs are engaged and the two hand winches are turned in the direction marked Heben . (Note: Although the operation appears to be quite simple, the actual work involved to prepare the trailer, load the vehicle and reconnect the platform is a task that took a crew of five experienced men at least 90 minutes to accomplish.)

e. Steering

(1) Steering is accomplished by means of a drawbar attached to the prime mover. When aided by rear steering, the turning radius is approximately 50 feet. All four wheels of the front bogie assembly steer by means of the draw bar. The linkage is such that the wheels are always tangent to an imaginary circle.

(2) Rear bogie assembly wheels are steered by the trailer driver who operates a steering wheel. To aid the trailer driver in steering when under full load, a double-acting air piston is connected with the linkage so that power is exerted whenever the wheel is turned. All four wheels of the rear bogie steer differentially so that they are all tangent to the same imaginary circle that the front bogie wheels are.

(3) The air for steering and for the air brakes is supplied by the towing vehicle. Provision is made for four air reservoir tanks, one of which is on the front bogie and is used for the front air brakes. The other three tanks are positioned on the rear bogie. One of these is used for the rear air brakes; the other two are used for steering purposes.

(4) The driver on the rear bogie is provided with a steering indicator dial on the steering wheel column. A small indicator lamp is placed on each side of the dial. It is considered that these lamps are provided so that the driver of the prime mover may signal steering instructions to the trailer driver. To the left of the trailer driver's compartment is a hand wheel that applies the brakes on the wheels of the rear bogie by means of a worm and gear linkage. This is probably used only for parking.

f. Conclusions

(1) This transport trailer can be used to provide a loading ramp for railroad cars.

(2) Its gradual angle of load when the platform is lowered aids in loading.

(3) The rear steering, air boosted, makes this trailer very maneuverable so that it can negotiate sharp corners on relatively narrow streets. This feature also makes it very easy to back the trailer.