well thursday morning my world came crashing down litterally. i was delivering 20 ton of beer to tesco middlewich im put on a bay and i was a bit tight so was asked to roll off a bit .my keys were in the office but theres a slope there so i let the handbrake off rolled forward an inch or 2 and put handbrake back on i got on my bed and felt them take the first pallet off .so im in the land of nod when all of a sudden i here a loud crash and bang my wagon has rolled off the bay and hit a scanny waiting to tip head on my truck was tottalled and the scanny well thats gonna be expensive.ive now been suspended cuz tesco have decided to get involved i cant for the life of me work out how it happened or anybody else the truck was a nreg and the trailer 10 year old so everybody is going on age and the weight of the load .at this moment i have no job as the agency i work for is only a small one and this company use all his drivers so no other contract for me to go on .so it looks like i will have to eat humble pie and go back tramping as at the mo these are the only options open to me and one of them being the continent .any ideas or advice welcome cheers jonah 
Can’t offer any answers, I’m afraid. Just wanted to say, hope you get back on your feet.
Oh and - you must have severely filled your shorts 
25yr ban, £1,000,000 fine, life imprisonment… 
Please don`t ever become a magistrate, Rob
Regards
Trev
Trevor Parry:
Please don`t ever become a magistrate, Rob
Regards
Trev
WHY NOT 
What u tryin’ to say 
You must be in a good mood Rob, you’re letting him off lightly. 
Coffeeholic:
You must be in a good mood Rob, you’re letting him off lightly.
Aye, finished before teatime today which I’m still struggling to get over the of 
back to the original topic… …as it would be just to much to have another farce like last week… … surely it was a mechanical fault jonah… even though you released the park brake whilst engine not running, i can see no other reason than some kind of serious defect with the motor… ive done exactly the same… today infact at barnsley… at the end of the day the motor needs inspecting and surely the fault will be found… hope you get it sorted man …
Bad luck Jonah mate. Hope you get out of it ok, and try and put it behind you.
Mal.
Jonah, from where I’m stood Tesco are to blame for this sad episode for allowing you to stay in your vehicle without your keys, they are contravening every H&S reg that is out there (I know), what you did was wrong by moving the vehicle in the way that you did, if you applied the handbrake correctly after you moved the vehicle and you are sure of that not in a month of Sundays would the vehicle have moved on it’s own again (I know), I suggest that if you are a member of a union take your case up initially with your local rep, also Tesco are concerned in the first instance about allowing you to stay in the vehicle in the first instance and are collecting any evidence to put forward in making a case against your companies insurers, personally if I was in your position I would not be to concerned about the case because of negligence on Tesco’s behalf, I have always had good representation from my union, other than that I suggest you have a walk to your local CAB and see if they want to get involved other than that good luck.
Lostpup:
Can’t offer any answers, I’m afraid. Just wanted to say, hope you get back on your feet.Oh and - you must have severely filled your shorts
No he (please let this one past the censors) [zb] the bed
Sorry Jonah, its not a laughing matter & I hope you get more work soon
Sorry, but rules is rules! L.
thanks for all the replys guys as it stands ive heard tesco are now introducing chocks for the trailer wheels im still suspended indefinatly .got a couple of numbers for jobs so hopefully i,ll get one of them .its tramping but eh youve gotta keep paying the bills.cheers jonah
hey jonah…keep us updated on this one… will be interesting to see what the end result is…terry
Jonah
Here’s something which may interest you. If you go to get unemployment pay you will find that it is ilegal to suspend someone pending an investigation without pay in the UK or Europe. You agency must pay you 40 hours basic by law.
If anyone tells you different I can tell you that in 91 I got suspended for refusing to drive a wreck when I worked for Fed Ex. Not only did I get paid for the week because the company told me it was law but because I lived 40 miles from the depot and the tractor unit was usualy kept at home, I had no way of getting home the day I was suspended so they gave me a company car for the week. Some suspension … more like an extra weeks holiday…
On some older models if the engine is not running, and so the compressor also, once the handbrake is released although re- applied it does not re-engage. In 1978 a driver was killed at Swifts in Northampton after such an event.
cheers for ya reply pat im thinking of phoning daf for some info so as soon as i find out whats going on i will let everyone know the company want me back but say they cant have me back until tescos have done their investigation which i find baffling as no tesco employee or truck were involved or injured apart from the fact i was on a bay and they had already taken a pallet off i cant see there problem 
Jonah, sorry to hear what happened.
You haven’t mentioned any time frame over which these various events happened and only you know how tired you were so as to allow for the possibility of human error to play a part. However, as you seem convinced that you did everything correctly, consider the following.
Firstly, so as to understand the possibilities better, a non-scientific explanation of how braking systems work. Con & Use Regs do not allow vehicles (and trailers) to be parked ‘on air’, hence the advent of Spring Brakes some 30-40 years ago.
As I have previously mentioned elsewhere, the first portion of the Parking Brake is a ‘progressive brake’. It is your Secondary Braking System, whereby if the foot control valve fails, you can apply the brakes to most, or all, axles (depending upon manufacturers design) and slow the vehicle progressively bringing it to a halt.
Once you move the Parking Brake ‘over the notch’, generally, air is exhausted from these additional axles and the air to the Drive Axle is ‘dumped’ allowing the spring brakes to secure the vehicle — Hence the vehicle is not being parked ‘on air’.
So what can go wrong? I can’t remember where, but I did read something recently (possibly in CM within the last 12 months) of a similar situation where a vehicle rolled forward whilst being unloaded. If I remember correctly, it was eventually established that Parking Brake was not securing itself adequately ‘behind the notch’ with the result that vibration could allow it to release itself.
If anyone else remembers reading the story, perhaps they could point us towards the origin.
Another possibility is that Daf’s of this ilk were often configured with a ‘Pressurised Service Line’. I am presuming that the vehicle in question was an artic. In this set-up, application of the Parking Brake not only dumps air from the drive axle, but also provides positive pressure to the trailer axles. Obviously this arrangement calls for a slightly more sophisticated configuration within the Parking Brake assembly.
It is feasible, and I stress that this is only a theoretical possibility, that your application of the Parking Brake applied the trailer brakes, but failed to dump the air from the Drive Axle. Dependant upon how ‘leaky’ the system was, and how many times, not only did they run an MHE onto the trailer, but also across the leveller, the trailer suspension would be trying to self-level and cause the air reservoir to diminish.
Of course, when the air pressure reduced sufficiently, then the Spring Brakes would have applied automatically, but there is the possibility of a ‘window’ whereby the Pressurised Service Line was not fully braking the trailer, and being heavily laden, allowed the whole vehicle to roll forward. Unlikely, but possible.
So, that said. What to do?
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Apply in writing to the Data Protection Manager at the depot for copies of any relevant videotape evidence both covering the outside bays and the warehouse doors from inside. If they refuse, make the same application to head office indicating that any refusal/delay will be the subject of a complaint to the Data Protection Registrar.
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Obtain a copy of your tacho chart, preferably double size, which you can use to correlate any time differences between the times shown on the video and the setting of the clock in your vehicle.
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Contact Daf’s TechnicalDepartment, quoting the VRM of the vehicle and enquiring if there have been any similar incidents reported, whether that vehicle had ever been subject of a re-call or service bulletin, concerning the Parking Brake assembly. Additionally, ask if there are any situations whereby such a fault could arise through poor maintenance, and particularly, due to moisture resulting from a failure to change the filter in the Air Dryer, or any other assembly. At the same time enquire as to the replacement guidelines for such filters.
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Report the matter to VOSA. Yes, I know it sounds extreme, but if there is a manufacturing/maintenance issue, then they may have prior knowledge or involvement.
As I said at the top, only you can judge the possibility of ‘human error’, so if you have identified something that could be a danger to all of us and the general public, then I, for one, would certainly like to be made aware of it.
Keep us informed.
Jonah, I think you’re going to owe me a pint or two
Having turned off my computer off whilst a thunderstorm passed overhead, I picked up an old magazine and found the following
Late last year I was engaged by a truck fleet operator to investigate an apparent failure of the park brake on a Daf eight-wheeled tipper. The results should serve as a serious warning to operators and vehicle manufacturers.
The incident occurred when a laden truck was driven up a ramp to the loading area of a cement plant. The driver set the park-brake. The park-brake lever remained where the driver had set it. The vehicle was on a slight incline.
The driver then headed for the rear of the vehicle to release the tailgate-retaining hoop. As he began to return to the cab, the vehicle began to roll back. Mercifully, the driver was able to jump clear. Only when it struck a wall did the truck come to a standstill.
The Daf dealer which had supplied the vehicle 18 months earlier insists that the driver must have failed to set the handbrake correctly. This was why I was called in to inspect the vehicle, a 2002-registered 340hp Daf CF 85 eight-wheeled tipper fitted with a Knorr-Bremse DPM 92D park-brake valve.
The valve is designed to supply a precise and gradual inverse air pressure to operate spring-brake actuators. The handle is spring-loaded and should automatically return the brakes to the “off” position.
When the lever is pulled fully back to the “park” position it should automatically lock into place. The lever should remain in this position until the driver lifts the collar, releasing the locking mechanism.
If application of the brake lever is incomplete and the driver fails to ensure that it is locked in the park position, the return spring should cause the lever to return to the “off” position. This evidently did not happen on this occasion.
When the park-brake lever is in the central position, only partial (secondary) braking is being applied. Held in this position by friction, the lever could give a driver the impression that the park-brake is fully applied.
I carried out a close examination of the park-brake valve assembly and found that the lever mechanism’s protective plastic dust cover was damaged. I took the valve to the IRTE head office in London for a second opinion. It was agreed that there may be a fault with the plastic dust sleeve which could affect application of the brake.
I then visited Knorr-Bremse in Bristol where a bench test of the valve assembly was carried out. During the bench test we were able to replicate the seized position while the valve was connected to a supply of compressed air. In this position the hand valve would seize with between 35 psi and 60 psi of pressure applied through it.
It was considered that with this amount of pressure still being applied through the braking system to a vehicle in good working order there would have been enough braking force to hold it on a slight gradient.
With the hand valve in this position we simulated the normal vibration that would be expected with the engine left running while the driver climbed out of the cab. To our surprise, the hand-valve sprang off after one or two minutes. I was also able to create the same effects with another valve of the same design.
I believe the evidence points to the incident at the cement plant being the result of a faulty dust-cover holding the brake lever in the secondary position. The forces acting on the brake system created by the vehicle resting on an incline, coupled with the internal return spring overcoming the friction forces holding the lever in the secondary position, caused the park-brake lever to move to the “off” position with a snap.
I also believe that the park-brake was set to the secondary position and not to the park position. The defective dust-cover and not driver error is to blame here. Had the dust cover not gripped the shroud, it would not have remained in the secondary position, and the driver would have applied the park-brake to the correct position.
All park-brake levers like this, and their dust-covers in particular, should surely be inspected carefully as a matter of urgency, and routinely from now on.
I would like to see a recall of all trucks with this kind of park-brake valve to establish whether this is an isolated incident or there is indeed a potential life-threatening fault with this valve.
Graham Doughty
Transport Management Consultants
Chislehurst
Kent
The above is reproduced from a letter published in the March 2004 edition of Transport Engineer, and after having to re-type all that, let’s call it a bottle 
Whilst I have not obtained permission to reproduce the letter on these forums, as it is already in the public domain, I do not envisage the author objecting.
However, before using the letter in respect of your own situation, I would consider it only courteous for you to contact Mr Doughty with details of your experience in order to not only confirm that a similar make/type of valve/shroud was fitted to the vehicle you were using, but also to assist him with his investigations into this matter and the clients for whom he is acting.
krankee your a star .cheers for that mate its much appriciated
Jonah:
krankee your a star
Seconded!!!
Great peice of research Krankee… and shows the true benefit that can be had from the variety of members of TruckNet UK…
Rikki
Carl, any developments on this issue?
If there is a design problem, then I’m sure both Daf and Knorr-Bremse would like to be made aware of it (along with a few thousand drivers) 