1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156 
Road and workshop
Page 48
If you've noticed an error in this article please click here to report it so we can fix it.
Loads and forces (7)
by Handyman
• Although it may seem at first sight anomalous to bring up the matter in midsummer, the question of spills occurring on snow-bound road must be dealt with in this series. On such roads, many spills are brought about on descents by no more than a sudden urge to change down: the driver feels that he is going too quickly and must drop a gear or two, which has exactly the wrong effect and will produce a slide in most instances. The whole situation is worsened by the quick and unavoidable speed increase during the operation, and the high resistance at the driving axle as the clutch is engaged.
It is of advantage for drivers when under safe conditions to familiarize themselves with the retarding values of various gears when on snow. This will enable them to select the most suitable gear for a difficult descent, one that will play its part in conjunction with light, or if needs be intermittent, braking.
One of the major causes of downhill accidents on snow, particularly among younger drivers, is the habit of tackling the route to the top of some icy or snowbound hill without thought that others may already be in trouble, either on the way up or down. By the time they meet another vehicle in trouble, it is then too late to stop or even control their own vehicle ; chaos follows. This is an all too frequent happening—it may be the first and only lesson needed by a driver, but it is totally unnecessary.
The "let-me-get-at-itattitude in an enthusiastic but woefully inexperienced
young driver can cause trouble on icy hill climbs when he feels that he must "show 'ern". He makes his own dash at a hill, only to find that the line of best adhesion is already being used; his subsequent attempt to rush by in the rough ends in an abrupt stop, blocking the road to other users.
About the worst driving hazard met is 'black ice"; often there is nothing to indicate a change in road condition. Rain may be freezing on the ground on contact, and particularly in the dark this is, a great danger. In the early hours it is not uncommon to find wet roads on a motorway or clearway with safe wheeladhesion conditions generally except under some cutting or under a bridge arch where a wind may have frozen surface water so that there is no adhesion. This is all too often why a vehicle may be operating safely at near full throttle one second, and be in an uncontrollable spin the next.
To see a large vehicle slow down and stop on such a surface and then watch it slide gently sideways down the road camber to the kerb, is enough to drive the point well home.
There is no simple drill to deal with these conditions of "black ice" except to be wary of rain in winter when it is known that the temperature is near freezing point; the most dangerous period is often between midnight and 6 a.m, when a night driver's earlier alertness is no longer so keen: in daytime it is always possible to assess road cond itions with more certainty.
Where ice is expected to form in cuttings, past the corners of walls or buildings, etc, avoid abrupt changes of speed, steering or braking. Also drive with a much wider gap than normal between vehicles, and if caught out by ice at speed and a breakaway begins, either declutch or slip into neutral and let the vehicle run itself down; no braking should be attempted if there is a clear road ahead.
As a rule if a slide or slip is starting, or the vehicle is found to be veering around on the steering, the action of freewheeling on all wheels will steady it and it will run on course. If there are obstructions ahead and speed must be lost quickly, still use the neutral technique but move the vehicle gently to the kerb; do not swerve it in, let it roll in at an easy angle. Usually whatever grit is arbund will be found close to the kerb, within a foot or so away, and once in this area braking can be applied gently.
Drivers of experience who know they may meet clear or black ice are constantly on the alert in another way— by their hold on the steering wheel. With one hand they can "feel" the amount of adhesion between tyres and road by lightly moving the wheel across its normal free-play point from side to side and checking resistance to further movement. A solid stop across the free-play point is good adhesion; a spongy or widening gap in the play indicates poor tyre-to-road contact.