Ukhtysh. The Time of Centaurs

The Time of Centaurs

No matter what you say, any wheeled ATVs are designed for driving on roads, even very bad ones. A tracked vehicle, on the contrary, constantly lays its own roadbed under the road wheels, which makes it a real off-road vehicle capable of overcoming soggy plowed land, peat bogs, waist-deep snow, and rocky fords. So why haven't everyone who needs to get to remote places bought themselves tracked tractors? Fortunately, quite a few were made in the USSR, and buying some GAZ-71 decommissioned from army service is quite inexpensive?

The thing is that a purchased tracked vehicle still needs to be operated. And here a mass of problems arises. Not only are traditional steel-tracked ATVs strictly forbidden to enter asphalt (we all remember what the tracks of the Kantemirovskaya and Tamanskaya divisions' tanks did to Moscow streets in 1991 and 1993). But the very operation of a tracked vehicle costs many times more than a wheeled one. It drinks fuel in barrels, it's not easy to drive, and there's no comfort. There are, of course, such "beasts" as the "Bobr" or the Swedish Hagglunds Bv-206. But they are still too large. Buying one for private use is like buying a bus. If only one could take a regular SUV and put it on tracks... But that's impossible!

I myself sincerely thought so until I saw at an exhibition of equipment intended for oil and gas workers nothing less than the most ordinary canvas-topped UAZ... Only instead of wheels, the vehicle rested firmly on tracks. It turned out that the vehicle is called the "Ukhtysh" and that this centaur was made in the town of Zavolzhye, near Nizhny Novgorod, but not at the Zavolzhye Tracked Tractor Plant, where the GAZ-34039 and "Bobr" are produced, but at a young enterprise called the "Zavod Vezdekhodnykh Mashin" (All-Terrain Vehicles Plant). The curb weight of the "Ukhtysh" is two tons, the dimensions are like a regular UAZ, and the rubber-metal tracks allow operation on asphalt. In a word, just what is needed! And how many vehicles have been made? Only one? I suppose it's impossible to take it for a spin yet?

On the Move: First Impressions

My second date with the "Ukhtysh" took place at the entrance to the track where all Zavolzhye tracked ATVs are tested. After thoroughly climbing over the vehicle, I realized that the "Ukhtysh" is not a UAZ on tracks at all. In front of me stood an original vehicle, in the design of which some Ulyanovsk components and body panels were used. The basis of the design is a steel "boat", in which a carbureted UMZ-421 engine, a regular four-speed gearbox, a transfer case, and the final drive housing of a Ulyanovsk reduction axle with a corresponding final gear are mounted.

But further on, the mechanics start to differ. Between the main gear and the final drives are the side friction clutches, which are multi-plate clutches. Some discs are engaged with the drive shaft, and torque is transmitted to the driven discs connected to the drum. A brake band is located on this drum. By turning to the side, you disengage the friction clutch of the lagging side, torque stops being transmitted to it, and goes entirely to the advancing side. And you brake the lagging side with the band brake. Ideally — depending on the force applied to the steering wheel. The greater the braking torque, the smaller the turning radius. The friction clutch itself has one turning radius, around the track. All other radii are selected by braking. Generally speaking, the side friction clutch is already an anachronism today, being replaced by hydrostatic steering mechanisms. But friction clutches are cheap and reliable. And since the task of the creators of the "Ukhtysh" was to bring to market a simple and cheap-to-operate ATV, these exact units were used.

The track has a rear-mounted drive sprocket (at the front is the idler wheel, which serves to tension the track), six road wheels with lever-torsion suspension, and three support rollers. The rollers themselves are double (the ridges of the track guide run between them), aluminum, with rubber tires. The front pair of rollers is equipped with an oil shock absorber.

The designers are very proud that they manufacture the rollers themselves, using the same technology as the rubberized rollers of combat tracked vehicles. The tracks themselves at first glance strongly resemble the tracks of the "Bobr", but only at first glance. The "Bobr" has tracks consisting of metal track shoes, each of which has a metal pad attached. The main idea of the new track is the presence of a rigid guide, which provides, among other things, the propeller rigidity of the track, that is, rigidity in the direction parallel to the vehicle's axis. It is precisely the insufficient propeller rigidity that explains the "Bobr"'s tendency to throw its tracks at every convenient opportunity. At the same time, this apparatus provides reverse rigidity. To ensure the necessary width and grip on the ground, elastic widening pads are installed on the track. When driving on hard ground, they do not touch the surface at all. The widening pads could be rigid, but in that case, they would break when hitting obstacles. The idea of a track with removable widening pads is not new; the Germans put them on the PzKf VI Pantera, but there they were rigid and broke desperately. The "Ukhtysh" track is a conglomerate of all the laboratory's developments in recent years.

Firstly, a rubber-metal joint (RMJ) is used to connect two adjacent track shoes. This, on the one hand, eliminates the friction of the pin against the metal of the track link and wear at this joint. Each track shoe is equipped with two pins. The pins of the two track shoes are connected by links, to which the widening pads are attached. Generally speaking, the RMJ is not news; the track design of most of our tanks is based on the RMJ. But tank track shoes are forged, with machined ridges and pin holes.

The "Ukhtysh" track turned out to be very manufacturable. Two ordinary pipes are welded with plates to which a one-piece stamped ridge is welded, and this entire structure is baked into a rubber-cord shell. This provides a rubber tread on which ice and snow do not freeze (a problem characteristic of all-metal tracks), as well as asphalt-friendliness.

The interior layout of the tracked "Ukhtysh" is completely no different from the interior of the most ordinary "commander's" UAZ, except that instead of a steering wheel, a small handwheel from a metalworking machine is installed, and to the left of the steering wheel is a pressure gauge showing the pressure in the pneumatic line... The fact is that the side friction clutches are controlled by pneumatics. Turn the handwheel to the left — you turn on the pneumatic valve, disengage the discs of the left friction clutch, and engage the band brake of the left drum; turn to the right — the same thing happens on the right side of the transmission.

But enough technical details, it's time to try out how the "Ukhtysh" drives! I open the UAZ door, cut off at the upper hinge, and climb into the driver's seat. Yes, now it's clear why the steering wheel was replaced with a tiny handwheel. I suppose if the steering wheel had its usual dimensions, I simply wouldn't be able to squeeze past it, but this way — not very convenient, but quite possible. I turn the key, listen to the starter motor whine for a few seconds, and press the gas pedal "spoon" to the floor. The three-liter Ulyanovsk "four" sneezes, spits out a cloud of bluish smoke, and finally begins to run smoothly and rhythmically.

"Let's start in second," advises Sergey, a professional test driver sitting next to me. The crunch of the gear engaging — off we go! I immediately realize that some automotive skills need to be left overboard. The thing is that the experimental vehicle is equipped with a compressor and pneumatic valves from a Pavlovo bus, and the friction clutches are controlled on an "all or nothing" basis. So the angle at which the vehicle turns is set not by the steering angle, but by the time you open the right or left valve. Get distracted, hold the handwheel in the turned position for an extra second, and one track brakes completely, and the vehicle itself rushes off the trajectory you want to direct it along.

You instinctively release the gas and feverishly spin the handwheel in the opposite direction, and the vehicle, which has managed to lose momentum... rushes into the opposite ditch. It took me about ten minutes to adapt to driving. Yes, this is somewhat longer than the time needed to get comfortable with the extremely simple controls of the Swedish Bv-206, but significantly less than what is required to penetrate the secrets of handling the levers of the "Bobr". Well, once you get comfortable, you can also engage third and fourth gear.

The speedometer needle dances between 40 and 50, and judging by subjective feelings, it's not lying. I become bolder and bolder, throwing the vehicle into the assault on the bumps, pits, and swampy sections of the testing ground. The "Ukhtysh", clever thing, literally does everything by itself. By the way, glancing sideways, I discovered that the transfer case control lever is in the "low gear engaged" position. I ask Sergey — what will happen if I engage direct? He just laughs in response: "That's not low gear, that's high gear."

It turns out that from theoretical considerations it would be optimal to have a main gear with a gear ratio of no more than 1:2 and final drives with a ratio of about 1:2.5. But in order to use standard UAZ reduction axles with a ratio of 1:2.77 and serial final drives with a ratio of 1:3.18 (the same final drives are used in the "Bobr"), the designers needed to redesign the transfer case in such a way that the reduction gear became an overdrive, with a ratio of 1:0.51. We never engaged the direct gear, which plays the role of a reduction gear in the "Ukhtysh". It wasn't needed.

Water Test

Sergey suggests: "Well, shall we go to the Volga? We'll ride there and swim"... On the way, I evaluate the suspension of the "Ukhtysh" in the most positive way. In my combat expedition youth, I had to ride tracked ATVs quite a bit, and almost all of them suffered from longitudinal pitching. You drive on what seems to be a flat road, but you are rocked like a longboat in a five-point storm: up and down, up and down, from bow to stern. The "Ukhtysh" does nothing of the sort. Longitudinal pitching begins only when the road itself is an alternation of bumps and hollows and the suspension hits resonance.

Also, the suspension of the "Ukhtysh" is notable for its excellent energy capacity. Package torsion bars made of four rods are used on the vehicle. They are both simpler and more manufacturable than pre-stressed single-rod torsion bars, which place very high demands on steel quality and tuning. Here we are racing through a floodplain swamp. Suddenly, right in front of the nose, a rather deep ditch appears, hidden until now by sedge thickets. I grip the handwheel tighter, expecting a serious blow, and press the brake. But the blow turns out to be quite tolerable. Actually, I could have not even reduced the gas. Sergey laughs: "More gas, fewer bumps...".

The only thing that spoils life is that the needle showing the coolant temperature periodically hints to us that the engine is about to boil over or has already boiled over. The fact is that hot air from the engine is not thrown out under the bottom, as in conventional cars, but passes under the floor of the passenger compartment along the entire "boat" and exits through several narrow slots in the rear side. On the experimental vehicle, these slots turned out to be somewhat smaller than needed. We have to open the hatch in the floor of the luggage compartment leading to the transmission compartment. To some extent, this solves the problem, but the noise level in the cabin becomes such that we have to shout.

The "Ukhtysh" is generally a rather noisy vehicle. But the creators of the vehicle assure that they have already figured out how to cope with overheating and radically improve sound insulation. Actually, the experimental sample, which is a running stand for testing the characteristics of the suspension, transmission, and testing the track design, simply did not deal with these issues.

A rather wide channel blocks our path. Well, shall we turn around? "Why, let's swim!" commands Sergey. Ah yes, it also swims! After all, both the "Bobr" and the "Ukhtysh" grew out of the same experimental ATV created in the laboratory of all-terrain vehicles of the GPI.

I carefully drop the wide nose of the vehicle into the water — and now we are swimming. It's just not clear where, since all the windows instantly fogged up. I wipe the glass and see that we are swimming completely in the wrong direction. I turn the handwheel, blocking one track, but practically nothing changes — it seems the "Ukhtysh" has absolutely no intention of turning anywhere. "Engage fourth and full throttle," advises Sergey. The water under the track guard of one side boils, and the "Ukhtysh" lazily begins to turn in the desired direction. That's good, now we are aimed perpendicular to the shore.

Now let both tracks row. I wonder how we'll get out here — the shore is quite steep... No problem at all. At some point, I feel the tracks catch on the bottom, immediately engage second gear again, for a second the wide UAZ hood obscures the sky, then smoothly lowers — and that's it, we're on the opposite shore.

After bathing, it turns out that the "Ukhtysh" has practically stopped obeying the steering. "It's a normal thing, we scooped water into the boat, so the friction clutches stopped working normally," Sergey and Alexey reassure me. "We'll drain the water now, and everything will be fine again." Here, by the way, it turns out that the drain plug on the "Ukhtysh" is located not too successfully, on the bottom under the engine. As a result, first you have to crawl under the vehicle with a wrench, and then look for a position so that most of the water still pours out.

On production vehicles, everything will be much simpler, since, firstly, the location of the kingston plug will change, and secondly, the equipment of the ATV will be supplemented with a bilge pump. In addition, an automatic flap should appear that prevents water from pouring into the engine compartment when entering the water. And yet I would not dare to swim across a river with a rapid current on it. The speed of swimming due to the rotation of the tracks is too low, and the vehicle steers too poorly in the water. However, there is an old proven expedition method — hang an outboard motor, such as a "Veterok", on the rear side of the boat. And the speed will increase from 3–4 kilometers per hour to 10–12, and controllability will appear.

The carbureted UMZ-421 with a volume of 2.9 liters copes well with its duties, but a diesel would still be better.

The main cause of overheating is the too-small slots for exhausting hot air in the hollow rear side.

The fuel tank filler neck located above the muffler is not the best solution from a safety point of view.

Turning the handwheel opens and closes the valves of the pneumatic system that controls the friction clutches.

Pressure in the pneumatic system is created by a compressor from a Pavlovo bus.

The design of the "Ukhtysh" uses many parts from serial machines. For example, the idler hub is borrowed from a "Moskvich".

Torsion bar suspension allows relatively smooth passage over even serious obstacles.

Having ridden enough through the sands and swamps in the Volga floodplain, we return to the base, and I organize my impressions. To say that I liked the vehicle is to say nothing. I am sure that there will be demand for it, and what a demand. Especially if you replace the carbureted engine with a decent diesel. Moreover, both private clients who want to have a real ATV for hunting and fishing trips, and oil workers, and foresters, and security forces will line up. Currently, both the Ministry of Emergency Situations and border guards have shown interest in the vehicle.

In a word, work for the "Ukhtysh" will be found where you need to overcome real off-road conditions and don't need to carry large loads. For now, only the bonnet version will be produced, but a version with a "loaf" (UAZ-452) body has already been drawn. As for the units, any engines from the range used on UAZ vehicles can be installed on the "Ukhtysh". At the same time, it is expected that the "Ukhtysh" will cost half as much as the "Bobr", and many times cheaper than the GAZ-34039 or a used Bv-206. Operation will also be noticeably cheaper. For the Bv-206, one belt costs $3,000, and there are 4 belts in total. And if you drive over an obstacle that tears the belt, you will have to buy a new track. The "Ukhtysh" track costs no more than $1,500, and in the worst case, you will need to replace a couple of track shoes at 500 rubles apiece.

By the way, manufacturers guarantee a track life of 8,000 km, but according to their own calculations, the real mileage will be at least 30 thousand km. The widening pad of a track shoe holds at least 300 kilograms and is most often lost not due to rubber tearing, but due to the fixing pin flying out. But even if you lose all the widening pads, the vehicle will still not lose its ability to move.

The doors are cut to the upper hinge, and a wire guard protects against contact with the muffler when boarding.

The main gear is taken from a military UAZ axle, the friction clutch and final drives are original.

Each track shoe is a rubber brick into which a metal frame, two connecting pins, and a stamped ridge of the guide apparatus are cast.

And in general, one can feel that the interest in the vehicle is huge. While we were riding in the Volga floodplain, people approached us twice and offered to sell the vehicle. Well, the "Zavod Vezdekhodnykh Mashin" is used to such requests and offers everyone to wait until February. Well, for now... Can I, after all, dream? For example, about how great it would be to get such a vehicle into the editorial fleet and, without hesitation, get to the most inaccessible sections on trophy-raid tracks. And why not, actually? Dreams are good because sometimes they have a tendency to come true.

Background of the "Ukhtysh"

Light ATVs have been dealt with in Nizhny Novgorod since the late 40s of the last century. This topic was especially actively developed in the mid-60s. Even then, many enterprises needed vehicles capable of replacing the "Buran" snowmobile, inexpensive to maintain and quite comfortable. Then, at the Research Institute of Transport Engineering and the Gorky Polytechnic Institute, the Laboratory of All-Terrain Vehicles was created. The core of the laboratory consisted of teachers from the Department of All-Terrain Vehicles. The laboratory was engaged not only in tracked vehicles. Wheeled vehicles, screw-driven vehicles, and motor sleds were also developed there (by the way, the GPI-1910 motor sleds were closest to serial production, but there was no plant capable of mastering this technique). The notorious "Buran" snowmobile was also developed in this very laboratory. There were also military projects and projects of equipment for oil workers.

GPI-22, 1947, GAZ-AA units.

S-GPI-19, 1960, ZAZ-966 units.

S-GPI-17, 1965, MZMA-403 units.

S-GPI-37, 1968, GAZ-24 units.

Source: www.off-road-drive.ru