Great piece analysing the viability of this from Tom Harrington ADINJC member.

United Kingdom speed limits are a bone of contention with many drivers, but they are a vital part of the road network. They are the front line of road safety, as they dictate the speed of all traffic, and by setting maximum speeds for different types of roads, it means consistent regulation across the country.

It also means it’s easier to prosecute those who exceed the speed limit, whether it’s by police enforcement, or via the use of technology.

In Great Britain, the 70mph speed limit was introduced as a temporary measure in December 1965. It was often attributed to Barbara Castle, but at the time the Minister of Transport was Tom Fraser. The reason given for the 70mph speed limit was a spate of serious accidents in foggy conditions and is was also claimed the Ministry of Transport had been alarmed by A/C Cars testing their latest Cobra Coupe on the M1 motorway at speeds of up to 185mph.

It was confirmed as a permanent limit in 1967*, by which time Barbara Castle (a non-driver) had become Minister of Transport. Perhaps, the fact the average family car at the time could only just exceed 70mph had something to do with this. It should be noted that this limit applied to all previously “derestricted” roads, not only motorways.

Motorways are basically dual-carriageway roads which must not be used by certain groups’ of road user and it’s an offence to pick up or set down a passenger or hitch-hiker on any part of a motorway including a slip road**.

Traffic travels faster on motorways than on ordinary roads and you need to look well ahead and sum up developing traffic situations more quickly and have time to react correctly to hazards.

It’s also important that your vehicle is fit to cruise at speed, have sufficient fuel and coolant to take you at least to the next service area. There are those who claim that increasing the speed limit to 80mph would bring economic benefits and GB was some way behind other European countries.

On the other hand, environmental groups claim that the 90mph limit uses more fuel with a resultant effect on carbon emissions.  However, one other issue that needs to be considered is: is the average driver equipped to deal safely with the increased speed when his vehicle is travelling at approximately 120 feet per second?

In Ireland and the UK you must not drive faster than the posted speed limit for the type of road and your type of vehicle. The speed limit is the absolute maximum (not a target to be reached) and doesn’t mean it’s safe to drive at this speed in all conditions.

Vehicle technology is changing rapidly, as crash avoidance systems and autonomous technology are developed. Modern cars provide a smooth quiet drive, even at very high speeds, and therefore drivers are often insulated from any real sensation of the speed of which they are travelling.

The vehicle power means that it is very easy to creep above the speed limit. Indeed, drivers often cite this as a reason for speeding.  In 2013, 3,064 people were killed or seriously injured in the UK in crashes where speed was a contributing factor.

While more and more cars are incorporating automatic braking technology and most have anti-lock brakes, we can’t avoid 100pc human error and in the event of a collision, humans are the squishy filling in a steel sandwich.

*A/C Motor Holdings, Thames Ditton, Surrey. In the early hours of 11 June 1964, A/C took a 4.8 litre car on to the M 1 motorway to do a high-speed test run before the 24 hour Le Mans.


Full report can be found here  –