An interesting post and probably the appropriate place to mention my favorite truck. The Tatra T813 and the T815. The suspension on these two varients is aswesome, not to mention awe inspiring. Their offroad mobility and haul capabilities in the aforesaid enviroment are unparalleled.Some background on these marvellous machines before I describe them an further.In 1942, when the TATRA company was under German war industry supervision, a special 6x6 truck was developed, whose task was to operate in the most difficult terrain covered with snow and under temperatures deep below freezing point. For this purpose the TATRA-concept chassis with its rigid backbone tube and independent swing half-axles, as well as the air-cooled V 12 engine were further developed. The vehicle, designated as TATRA T-111, was never used in WW II but for its outstanding performance and driving qualities it formed a basis for later exports of commercial off-road TATRA trucks to the USSR in the late 40's and early 50's. TATRA T-111 was also used as a standard military truck for the Czechoslovak Army and many other armies of the former Warsaw Pact.Later successors of this distinguished truck further developed the design features of the TATRA-concept, making all the off-road vehicles particularly suitable for military use.
The T813 was introduced in 1965, produced at the Koprovince factory (Czechoslovakia), outfitted with a monstrous and torquey 17.6-litre 12-cylinder unit of 247bhp @ 2000rpm (very likely a highly reliable air-cooled diesel V12). It could haul up to 8.2 tons and was available in many forms, including the approprietly named 8x8 (4 axle) Kolos (collosal) towing truck. The T813 is probably the most widely known Tatra truck ever produced.
T815 & Unique Independant Suspension.
In 1982 a new T-815 model family of both commercial, and military trucks was launched. This family of trucks, still based on the same TATRA-concept principles, has over time been developed into the commercial TERRNo1 family, and military ARMAX and FORCE families, the latter two distinguished by their proximity to standard production commercial models is still produced with minor improvements to this day in a multitude of different versions. The rather conventional looking T815, available in 2, 3, or 4 axle format, was initially equipped with a 10-cylinder (an air cooled diesel, naturally) engine of 15.8-litres and with a torque of 1010Nm (@ 1400rpm) on tap. Later on 19-litre 470bhp 12-cyl. (with torque of either 1130Nm or 1295Nm @ 1400rpm) and 12.7-litre 8-cyl. (with 840Nm @ 1400rpm) units became available. Carrying capaciy of a typical T815 is about 14 or 15 tons and maximum speed is around 90 km/h.
ARMAX family
Trucks or chassis based on production commercial models, meeting European emission, noise, and axle load standards
FORCE family
Special truck or chassis models, military or commercial, using several different makes of water-cooled engines over 300 kW, special or automatic transmissions, and other high-performance design features enhancing the outstanding off-road mobility of the TATRA-concept chassis.
Both ARMAX, and FORCE families of trucks or chassis use the latest results of TATRA suspension development - the so-called combination suspension, using a commercial name KING FRAMEĀ®.
Since WW II, more than 360,000 trucks and chassis using the TATRA-concept have been produced. Out of this number ca 135,000 units belonged to the TATRA T-815 and TERRNo1 families.
More than 8,700 units of TATRA T- 815 family military trucks and various types of chassis (4x4, 6x6, 8x8) were delivered to the Czechoslovak and, later on, Czech Army, as well as to many armies worldwide.
TATRA SUSPENSION TECHNOLOGY:
The independant suspension on the Tatra 13/15 is a very unigue piece of engineering. The Suspension consists of a central "backbone" which houses the lockable side- and inter-axle differentials, drive shaft and axles and traverses the lenght of the truck. Its available in 4x4, 6x6, 8x8 layouts.
The design eliminates torsion or bending of the chassis and superstructure,allowning safe and trouble-free transport of sensitive loads, special bodies or superstructures, high ride comfort, faster drive off-road and long life of the chassis as the driveline shafts and other components are covered and protected inside the "backbone" tube
the chassis can operate "frameless", which makes it possible to fix certain bodies directly to the chassis crossmembers.
All wheels are mounted on independent swing half-axles because of which each wheel moves up and down independently resulting in remarkably higher speed on rough roads and quick pass over obstacles coupled with unparalleled off-road and cross-country mobility.
Excellent absorption of shocks and vibrations caused by rugged road surface.Swing half-axles are extremely resistant against impacts and shocks.
The modular" design allows for a very high degree of commonality for commercial and military models.AWD 4x4, 6x6, 8x8, and 10x10 versions in production and different wheelbase alternatives available for each version making adaptation suitable as cargo or troop carriers, and particularly as chassis for different kinds of special superstructures.
lockable side- and inter-axle differentials.
The Latter T815s came with the King Frame supension with a light and heavy varient. The "light" version, using combination of coil springs incorporated inside the airbags, which are located above the "backbone" tube, and the "heavy" version, which uses a combination of leaf springs and airbags, located again above "backbone" tube and in this way protected against any impact or damage.
The principal effect of this design consists in eliminating the wheel camber, which used to be an inherent feature of unloaded TATRA trucks using the original TATRA suspension leaf-spring technology. With the "heavy" version, the combination suspension also features with a substantial increase in permissible axle load. Air pressure in the airbags, changing in relation to the load, keeps the position of the frame in a constant height, i.e. the position of a cargo body, platform, fifth wheel, etc., is always in the same height.
