Why not 40 mph?
Page 15
If you've noticed an error in this article please click here to report it so we can fix it.
Each time we test a truck-and-trailer combination we are reminded of the inappropriate speed limit of 30 mph which is still imposed upon such outfits in Britain, although articulated vehicles have been permitted to travel at 40 mph on normal roads since 1963 and both types are able to take advantage of the 60 mph limit on motorways.
Our experience of modern drawbar combinations confirms the industry's long-held view that these are fundamentally safer and more stable than artics of equivalent weight and are capable of stopping at least 'as safely and rapidly as a well-matched articulated outfit. In testing the combination which is reported upon in CM this week we deliberately duplicated the braking tests solo and coupled — and there was no significant difference between the stopping distances of the solo vehicle and the combination.
When, in March 1971, the Government sensibly removed some of the existing speed limit anomalies, it refused to alter the 30 mph limit on drawbar outfits, maintaining that this would not be safe until legal braking standards were raised, because there were -a great many" old vehicles on the road which had been given concessions on braking.
The time for reviewing the situation has now been reached. Relatively few "pre-1968 standard" trucks are still running and very few indeed in the drawbar trailer category. Yet the increasingly necessary raising of the limit to 40 mph is almost certain to be further delayed if it is to depend upon brake uprating, because no formal announcement on this is likely for several months. It now seems possible that no decision on brakes will be announced until it can be dovetailed with a statement about the introduction in July of alternative EEC standards for type-approved systems. We appreciate the complexities, but the Department could surely help the industry's planning and investment by indicating the lines that developments will take, both in brake standards and speed limits.