Looking at how steep that hill seems to be, I’d think it didn’t go far before hitting the cars. If the brakes ain’t faulty and the handbrake was put on properly, how can this happen ?
A job for Mulder and Scully
I’ve just realised how much that last bit sounds like the good old Prof’ Julius Sumner Miller. 
Happen a good job that those cars were there really! I guess that those perhaps only have a parking brake on the rear axle, I wonder if it just slid or maybe one of the springs was weak or broken in a spring brake unit and one alone wouldn’t hold it? Anyway we might know in a few pages time! 
Pete.
You just know this can only go downhill from here on in ,
it`s a slippery slope 
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enter>>> tknet csi
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agency ?
windrush:
Happen a good job that those cars were there really! I guess that those perhaps only have a parking brake on the rear axle, I wonder if it just slid or maybe one of the springs was weak or broken in a spring brake unit and one alone wouldn’t hold it? Anyway we might know in a few pages time!Pete.
I would be thinking along similar lines. Park brake mot test efficiency isn’t that stringent or put it this way, although fine on most gradients, it’s not enough to hold it on some of the steepest hills on the road network. Spring park brakes usually only on drive axle can be on others but tend to be specialist applications or heavy haul.
I think there must have been some brake force acting as it looks to have stopped fairly easily unless it didn’t go very far to start with.
Parking brake values at MOT are IIRC 12% of the train weight of the vehicle, easy to achieve if the brakes are applied on two axles, but ask anyone who has tried to get a 4x2 Scania artic with a GTW of 52tons through a test and they’ll tell a different story.
is that a wheel choc under the n/s rear wheel.
m.a.n rules:
is that a wheel choc under the n/s rear wheel.
Aye, it is. When was it placed there though, it could have moved with the truck as the road surface looks slippy or perhaps the cars reversed back into the truck! (joke!)
Would the gas be in liquid form, I guess that there wouldn’t be much weight over the driven axle if it was? 
Pete.
This mini bulk can carry 7.5t gas when fully loaded.
If nobody was injured,why did the ambulance attend?
Gas tanker = over reaction maybe ■■