GETTING OUT OF TIGHT CORNERS.
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WHEN ROAD an weather conditions conspire together, even the most careful driver may find himself and his lorry in difficult positions. Whilst there are many experienced men who know all the tips of the trade, a little observation shows that many drivers': on the road to-day have very little idea as to what to do in difficult and yet common enough circumstances. It is primarily for the benefit of these that this article has been written.
Apart from the risk entailed to the driver in particular, and other road users in .general, should a heavily-laden lorry get out of control, much damage may be caused to the vehicle itself, and the delivery of the load will be delayed. Minor troubles may also cause vexatious delays and material damage. For drivers engaged on cross-country routes,. the negotiation of steep, greasy, or slippery gradients is a common source of trouble. When making a descent, the golden rule is never to allow, the lorry to get beyond a moderate or even low speed. If a high speed is reached before the brakes are used, the pedal will, in all probability, have to be applied harshly (the instinctive action of the driver being rather to overdo the pressure), causing the rear wheels to lock and slip or skid over the surface. By a judicious and gentle application of the brakes at an early stage, and by leaving the engine in gear, troubles due to locking the wheels can be avoided.
In making ascents, chains are of great asoists,nce on frozen and slippery roads. If these useful adjuncts be not available, a temporary substitute, which is very effective, consists in wrapping a length of rope round the tyre and the rim of the wheel. Much can be done by handling the clutch and gears carefully and avoiding sudden acceleration. When making a start on a greasy or slippery surface, the clutch should be let in very gently indeed. Second gear should be engaged in preference to the first, provided that the engine will take dt, because the twisting effect transmitted to the rear wheels is thereby minimized, and this reduces the tendency to wheel-spin. On poor road surfaces soft and muddy patches are met with, into which one of the rear wheels may sink and become embedded. A similar trouble is often met with if, in attempting to pass anothervehicle, one of the rear wheels passes over soft and treacherous turf at the edge of the foad. " When a lorry becomes embedded in this way it is of absolutely no avail to " rev " the engine and engage the clutch repeatedly. This will simply cause the free wheel to spin round, or, if both are on soft ground, they will rapidly dig themselves into a _worse position, reducing ,the clearance between ground and the bottom of the differential case to the danger point.
Ensuring a Grip for the Wheels.
In either event, the aim of the driver should be to obtain a grip for the embedded wheel. First of all, the mud and stones in front of the wheel should be cleared away so far as possible, and the tyre can be bound up with a length ofrope. A piece of sacking or canvas can then be laid down in front of the wheel and pushed under the tyre as far as it will go. With this assistance the wheel will obtain sufficient grip to pull itself out when the clutch is engaged—in all but very exceptional circumsta.nees. In this connection it should be remembered that the attempt at getting away will be made more difficult if the front wheels are locked over.
In some cases, when driving at night, wnat appears to be a grass strip at the edge of the road may, in point of fact, be an undisclosed ditch. In these circumstances a detour to avoid an oncoming car may result in the two near wheels becoming deeply embedded in the ditch, with the lorry canted over at an alarming angle. It is usually hopeless to attempt to extricate the vehicle under its own power, a tow being required, as a rule. The best method is to pull the ditched lorry out backwards, along the route taken when going in. Before starting on this process as much of the load should be removed as possible. The attachment of the tow-rope requires a little consideration. In the absence of hooks provided for the purpose, the ends of the rear cross-member should be selected, the rope being also passed round the side members. Very often it is advisable to start the towing lorry with the rope slack, so that wben the rope tightens up a sudden jerk is exerted which will start the ditched vehicle on its way out.
This jerk should not be overdone, or the rope may be broken. The attachment of the tow-rope has already been mentioned, and deserves emphasis, because the writer has seen cross-members badly bent through the pull being applied near to the centre instead of at the ends.
Apart from the more serious troubles outlined above, minor difficulties are often met with which may produce disastrous results. Chief of these is skidding. It is sometimes quite impossible to avoid a skid, but a precaution which goes a long way towards obviating trouble is to handle the brakes very gently when negotiating greasy surfaces. Harsh brake application is almost sure to start a skid, and it is as well to remember that-suddenly to accelerate is almost equally bad. This is due to the fact that, to apply a sudden torque to the rear wheels, forwards or backwards, lessens the resistance of the tyres to moving sideways.
Another trouble, which is most likely to occur in the case of an inexperienced driver, arises when a kear is missed when ascending a hill. Suppose, for example, that a rapid change down from second to first speed is required, and that, owing to inexpert handling of the controls, the lorry comes to a stop with the gear lever in neutral. Before the driver has time to engage' the gear the vehicle will commence to run backwards downhill.
There are, of course, the brakes, but the speed will increase so quickly that, if the driver loses his head for a few seconds, the opportunity of pulling up will be lost. It is a great pity that more attention has not been given to the question of providing an efficient sprag in the transmission. system, and encouraging its employment, as the ordinary " external-pole variety is usually useless in an emergency of this kind, merely serving to hold the lorry when stationary but incapable of pullingit up should it have started to run back. The (nay solution with the orthodox vehicle consists of steering into the bank, kerb, or wall as soon as possible! , Last on the list of minor difficulties comes the question of manceuvring -a lengthy vehicle in a confined space. The lowest gear available should, of course, be used, and the clutch should be handled carefully, so as to avoid sudden and jerky movements. When possible, select fin individual of sufficient intelligence to give signals the meaning of which cannot be misunderstood.
In endeavouring to turn around in a narrow road or lane, much time and trouble can be saved by choosing a spot where there is a gateway or by-road which will add materially to the width available. It is as well to avoid manoeuvring close to a blind corner, as the sudden appearance of a fast touring car when the lorry is right across the road is somewhat disconcerting for all concerned