OT: tipper lorry crash in Bath

No idea - but with a tipper driver, all bets are off. They are by far the worst drivers on the roads.

When I heard about this crash (which sounds like it may have been due to a brake problem) AND heard that the driver was a teenager, it made me wonder if he'd even been taught to use the gears for slowing. For cars they're certainly not taught this but maybe for HGVs? Anyone know what the teaching is these days for HGVS drivers?

Tim

I was wondering how a truck braking system is able to become inoperable.

Gareth.

Many HGV's have some form of (semi) auto gear selection, so probably not taught. Lots of them have things like exhaust brakes also.

In this particular accident, the driver had only passed his test a few days earlier, and not in a tipper, so inexperience seems a likely factor.

Chris

He had long experience of heavy vehicles on a farm and had held an HGV3 or 2 for a (relatively) long time, however he had only just passed his HGV1 licence a few days before. It has been mis-represented in some news reports.

I cannot imagine how an air braked vehicle can lose braking ability to such a major extent.

I used to dirve 7.5 tonners many years ago, on those, there was a lever to boost the air supply on long descents, as the engine compressor couldnt keep up with demand (or something like that!)

Is that now automatic on bigger vehicles?

Wouldn't lack of air result in the brakes not releasing?

Only ever had one experience of driving an air-braked vehicle but I distinctly remember that the handbrake wouldn't release until the pressure had built up sufficiently.

Tim

Exactly, the brakes fail safe, if a hose gets cut or falls off, the vehicle stops solid, which is very embarassing when you are trying to pull away at a junction with some leaky old wrecker and it is sitting there in the middle of the junction being revved to get the air pressure up. You don't see that so often these days, but it used to be a more frequent problem. It also explains why HGV recovery vehicles have big long air brake hoses to feed the axles of the towed lorry, not to operate their brakes, but to stop them operating unwantedly.

A few reasons come to mind, overheating brakes causing fade out water in the compressed air system possibly freezing up.

Thats correct on all modern vehicles.

It did make me wonder - I thought all HGV brakes failed safe, ie on? It looked to be a fairly modern vehicle too?

They will if the failure is a broken airline not so with other issues

My guess would be brake fade too. Do any lorries have disk brakes yet? Certainly some coaches have "eddy current" brakes on the propeller shaft which of course don't suffer from fade.

The A46 down into Bath from Lansdown Hill (not the road he was on) has an escape lane for brake failure, as does one of my local hills. Before that was put in, lorries used to run into the pub on the bend at the bottom about once every ten years.

Lorries have had disks on the front for a long while.

...but once rolling if one continually dabs the brakes and the compressor cannot keep up...

Our 7.5 tonne tipper is full auto with actuators for clutch and gear change.

Anyway I thought minimum age for class C licence was 21???

AJH

Thanks, I did wonder. Obviously that will reduce the risk of fade; but presumably for an HGV with a fully loaded trailer, you may need help from the rears on long hills?

footbrake and one from the emegency brake.

The footbrake operates the braking system by applying air pressure to the braking system via a piston and cam (similar to how conventional drum brakes operate in a car), the emergency or parking brake operates by discharging air, allowing a spring to force the actuating piston accross operating the cam

The age is 18 if you have a cpc qualification

Thanks for the info. More here.

My daughter drives a class 1 HGV and a few nights ago, and on a fully loaded lorry (44 ton gross or so), had an airline under the trailer blow off a deffective connecter - and the first she knew about it was when the warning light and alarm activated in the cab when the tanks were almost empty and the air pressure low.

As luck happened, she was on a nice, flat dual carriageway and was able to pull into a safe lay by to do a temporary repair.

Before the question about ability: when she left school in 1990, she shunned the 'girlie' jobs (her words) and trained for four years as a vehicle mechanic - and decided 18 months ago she'd had enough of that and took (and passed first go) both her HGV 2 and HGV 1 tests within a month of each other. She could already drive 71/2 tonners as she passed her test in 1991 so she was able to skip one HGV test

Ormolu

Fine and good for her:)

A past girlfriend of mine was an Airline captain apart from all the other non lady things she did!, and was rather feminine with it all;!...

Used to know a girl who now drives class 365 EMU set's..