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 
Q The current C and U Regulations re' Id " quire an axle
Page 89
If you've noticed an error in this article please click here to report it so we can fix it.
spread of at least 38ft in an overall length of 42ft 7.75in. to permit running 32 tons g.t.w. an four axles. Could you comment on this requirement and the suitability of tractive units and trailers for running at these maximum weights.
AThe problem of obtaining the necessary
axle spread of 38ft within an overall length of 42ft 7.5in. is largely created by the present trend of vehicle manufacturers in meeting the need for easy forward-entry cabs. Such design entails setting the front axle back about four feet and, therefore, the overhang becomes excessive.
To obtain the necessary axle spread the maximum distance from front bumper to the centre line of the front axle must not be more than 28in. There is only one vehicle produced in the UK at present which meets these requirements and this is the Scammell Highwayman normal-control tractive unit.
To obtain the rear-axle position on the semitrailer and to apply the correct imposed load on to the fifth wheel of the tractive unit it is necessary to utilize a wide spread tandem bogie and this leads to excessive tyre scrub unless one of the trailing axles is of the steered pattern.