First reported UK Bridgestone DriveGuard puncture caused by roadside debris

Posted on October 14th, 2016 by Rob Marshall

blowout

You cannot fail to have noticed that there is an increasing quantity of detritus littering the hard-shoulders and central reservations of our motorways in recent years. I have and it could have resulted in a nasty accident, when a large metal object (I presume it were a bolt) skewered one of my rear tyres, while I was travelling at 60mph, early in the morning, several weeks ago.

I am not alone. Claims Management and Adjusting (CMA) has seen a 20% increase in blow-out, swerve, flood and fire claims in the past year, part of which it attributes to a ‘zero carriageway crossings policy’ that was adopted by Highways England from 2011, which was designed to protect the lives of workers. While this health-and-safety strategy appears to be reasonable, CMA claims that it is also “exacerbating the danger for road users”.

Philip Swift, CMA’s MD, has gone a step further, by stating: “We are extremely concerned at the increasing number of cases involving drivers swerving to avoid debris and fear it is only a matter of time before someone gets killed. Highways England contractors are paid a lump sum to provide barrier repairs, gully clearance and litter removal. However, the costs associated with closing a carriageway are a disincentive to removing larger items like burst tyres.”

“Even if a Highways Agency Traffic Officer (HATO), or contractor, does attend,” Mr Swift continued, “there can be a tendency to kick the problem to the side of the road and that puts lives at risk…shards from disintegrating debris can cause punctures, which can result in collisions. Debris can also impede drainage, leading to standing water, aquaplaning and possible crashes.

GEM’s real-world test

It is unsurprising that the first real-world, UK puncture of Bridgestone’s DriveGuard run-flat tyre, reported to its UK headquarters, was caused by motorway debris. The only problem was that it involved me, 40 miles from home on the M5 motorway at 12.30am. Having had relatives that had suffered sudden tyre deflations at motorway speeds, which resulted in them losing control of their vehicles (fortunately, they are still here to tell the tale), I was relieved that the only thing I noticed was the sound of a hefty metal object being ejected from the nearside rear wheel-arch at speed, shortly after I made a disapproving mental note about the detritus that littered the hard-shoulder, as I accelerated up a slip-road to join the northbound stretch of M5 motorway, near Cheltenham. Seconds later, while travelling at approximately 60mph, the car’s tyre pressure monitoring system alerted me of low pressure. Several more seconds passed, before it chimed again, warning me of a puncture and that I must stop immediately. Obviously, receiving two warnings in such quick succession indicated that there had been a sudden deflation but at no point did the car stray out of lane, or feel unstable; the only clue to a problem was a subtle ‘buzz’ from the affected nearside rear DriveGuard cover.

I pulled onto the M5’s hard shoulder and came to a gentle stop. As the motorway traffic was very light at that time in the morning, I selected the hazard lights and alighted to inspect the passenger side tyre with my mobile-phone’s built-in torch. Clearly, the DriveGuard had deployed its emergency run-flat mode, by appearing deflated but not fully-flat. After finding no obvious sidewall damage, I decided to continue on my way carefully.

With no tyre depots open in the small hours and my satellite navigation indicating that I had 36 miles of my journey remaining, well within the tyre’s 50 miles emergency run-flat mode design life, I continued my journey, albeit setting the cruise control at Bridgestone’s 50mph recommended maximum speed. I reached my destination safely.

The following day, I drove to my local Bridgestone distributor, who revealed that the tyre had not suffered internal overheating damage from being driven just over 40 miles in run-flat mode but, as you can see from the picture, the size of the hole, caused by the suspected bolt, rendered it irreparable.

In conclusion, the run-flat tyre had not only helped to prevent a loss of vehicle control but had also saved me from the potentially dangerous task of changing a tyre on a motorway hard-shoulder in the dead of night. Yet, it is possible that I could have saved over £100 on having to replace the tyre and a fair amount of hassle, if the entry slip-road was clear of debris in the first place.