Bus crashes in to a river in the Eastleigh area (26/06)

[greenline712]

On the assumption that it was a mechanical fault, I wonder whether commercial drivers have sufficient and suitable preparation for dealing with emergencies like that? Thankfully it's very rare that you get a runaway, but that makes it all the harder for the driver to deal with because it's so completely unexpected. I would like to think that if that happened to me, I would have the presence of mind to knock it into neutral or turn the engine off ... but am I confident that I would be able to think rationally and not just go into a blind panic, or freeze? Absolutely not.

Modern buses don't have gears as such ... they have push buttons for DRIVE NEUTRAL REVERSE. If the driver did experience a jammed throttle, there is little to be done other than brake heavily. Even a parking brake would not retard the bus quickly ... it is a 'parking' brake!

This incident reminds me of a Leyland National that I was driving some 45 years ago ... LNs had a semi-automatic gearbox whereby it WAS possible to deselect gears, but not immediately ... there was a delay of a few seconds before it took effect. This bus (probably 8 years old) suffered from a "racing" throttle; apparently a pin had come out in the linkage to the engine. Luckily I was driving up a slight hill, and was able to knock the gears out and stamp on the footbrake to stop the bus. It took nearly 20 seconds pulling on the emergency engine stop (at the back of the bus) to starve the engine of fuel before it stopped ... a VERY scary time!!!

Looking at the dashcam footage, it looks like the driver headed for the river as somewhere (anywhere!) to stop the bus. No driver training will include this ... how could it?

 

[Towers]

Modern buses don't have gears as such ... they have push buttons for DRIVE NEUTRAL REVERSE. If the driver did experience a jammed throttle, there is little to be done other than brake heavily. Even a parking brake would not retard the bus quickly ... it is a 'parking' brake!

There would presumably be nothing in the circumstances to prevent a driver from selecting Neutral, unless the gearbox would prevent that whilst in motion for some reason? Auto cars will generally allow it, certainly. I can’t say I’ve ever tried it in a bus!

By way of some light relief I have to say that your mention of a National with a “racing throttle” brings some interesting images to mind; some of the ‘yoof’ around here have “racing throttles” but thankfully not in Leyland Nationals!

Briefly, as it’s way off topic, an acquaintance occasionally tells a story of being a “breadvan” (minibus) driver in National Bus Company days and doing overtime on a ‘big bus’ shift with a National. Having reversed it out of a bus station bay and selected a forward gear he had a ‘moment’ and couldn’t work out why the bus wasn’t moving off despite the engine revving. He quickly remembered that this was due to the handbrake being applied, so he released it - without taking his boot off of the throttle. His passengers weren’t impressed…

 

[stevieinselby]

Modern buses don't have gears as such ... they have push buttons for DRIVE NEUTRAL REVERSE. If the driver did experience a jammed throttle, there is little to be done other than brake heavily.

Would the driver not be able to select Neutral while the bus was moving? Or turn the engine off? (I know that's very much the nuclear option if you then lose power assistance to the steering and brakes, but in that situation it seems like the lesser of two evils)

 

[greenline712]

Would the driver not be able to select Neutral while the bus was moving? Or turn the engine off? (I know that's very much the nuclear option if you then lose power assistance to the steering and brakes, but in that situation it seems like the lesser of two evils)

It might seem so, but the buses fitted with push-button gear operation do not immediately release gears if neutral is selected. Similarly, turning off the engine in the cab doesn't necessarily immediately turn off the engine itself. It is all down to electrics nowadays. A car is very different.
An emergency engine stop on a bus, and I dare say in a lorry as well, where the engine is remote from the driver, works by starving the engine of fuel.

We don't know what actions the driver took; nor do we know the condition of the bus. I daresay we will in time . . . perhaps, until then . . .

 

[Lewisham2221]

It might seem so, but the buses fitted with push-button gear operation do not immediately release gears if neutral is selected. Similarly, turning off the engine in the cab doesn't necessarily immediately turn off the engine itself. It is all down to electrics nowadays. A car is very different.
An emergency engine stop on a bus, and I dare say in a lorry as well, where the engine is remote from the driver, works by starving the engine of fuel.

We don't know what actions the driver took; nor do we know the condition of the bus. I daresay we will in time . . . perhaps, until then . . .

I was also once told by a fitter that the handbrake/parking brake won't apply above a certain speed either. Needless to say I took his word for it and never tested it myself!

 

[christopher]

Handbrake will apply regardless of speed, same as can knock this type of bus into neutral whenever you like

 

[whoosh]

Could it have been something in the engine bay, rather than a problem with the accelerator pedal itself?

This makes an interesting read - from Rob Haywood's site about his time with Leicester City Transport. He was later a bus driver in Hull, which also had Metro-Scanias.
Under 'photo 14' about the Metro-Scania:

Buses : Leicester City Transport

memories of leicester city transport and its buses

www.rhaywood.karoo.net

Management always denied power-surges happened, even when people were hurt, and even I began to doubt it - until I had one myself. It caught me completely unawares as it took off like a missile from a stop one quiet Sunday afternoon on a Hull council estate. I'd just set down a little girl, closed the doors, and had barely touched the throttle, and - Whoooosh - I was almost at the end of the street!! It made more smoke than I've ever seen from something that was not actually on fire, other than perhaps a Centurian tank starting up. The force actually pressed me into the back of my seat, an incredible experience, and one that I was very loathe to talk to anyone else about, given the wide scepticism around. It frightened me, and I was very much on my guard should it happen again, but it never did. I was very lucky in that instance, for there was nothing but a clear road in front of me, when normally there were some parked cars just beyond the bus stop. I dared not even change the bus when I got back to town, for what could I tell them, except to attract a heap of ridicule upon myself. I've even questioned whether I should relate it here, but I think it's time, whatever my old collegues may think. And no, it was not my imagination. My little old 2-ltr Peugeot couldn't take off like that.....
....I have a theory, a small one, that it was caused essentially by careful and slow driving. It seemed to happen to the steadiest of men, those that didn't rush unduly and took their time. Those that raced around, throttle to the floor, never seemed to experience this. I was on a Sunday service, running to time, hardly anybody on, and no reason to drive even remotely quickly. For crying out loud, that day I was almost asleep I was that laid back! So how? My theory is that slow driving, sometimes not much above tickover, allowed fuel to gather somewhere in the pump, unburnt. It would build up until, just the tiniest dab on the throttle would release the lot in one go, and whoosh, you were driving a rocket, with about as much control. Come on engineers, tell me that is wrong. How the hell else could it happen?

Another Metro-Scania (a London Transport one) famously ended up in Clapton Pond.

 

[philthetube]

Modern buses don't have gears as such ... they have push buttons for DRIVE NEUTRAL REVERSE. If the driver did experience a jammed throttle, there is little to be done other than brake heavily. Even a parking brake would not retard the bus quickly ... it is a 'parking' brake!

This incident reminds me of a Leyland National that I was driving some 45 years ago ... LNs had a semi-automatic gearbox whereby it WAS possible to deselect gears, but not immediately ... there was a delay of a few seconds before it took effect. This bus (probably 8 years old) suffered from a "racing" throttle; apparently a pin had come out in the linkage to the engine. Luckily I was driving up a slight hill, and was able to knock the gears out and stamp on the footbrake to stop the bus. It took nearly 20 seconds pulling on the emergency engine stop (at the back of the bus) to starve the engine of fuel before it stopped ... a VERY scary time!!!

Looking at the dashcam footage, it looks like the driver headed for the river as somewhere (anywhere!) to stop the bus. No driver training will include this ... how could it?

So I am not the only one, I had a National 2 with the same issue, fortunately I was only moving slowly and got it out of gear and stopped, no problem, the exhaust created a hole in the road however. There was no external fuel cut off on a national 2 which seemed wierd.

 

[Zamracene749]

Handbrake will apply regardless of speed, same as can knock this type of bus into neutral whenever you like

Not much use to stop a vehicle at roadspeed if the engine is powering.
Nor are the service brakes, they just aren't designed to dissipate that amount of heat. The friction linings begin to melt, then the lining between the drum and the brake basically evaporates and becomes a lubricant.
I've driven a car when the throttle stuck open at speed (not relevant to this event, but it was condensation frozen by the carburettor in the throttle cable) its a scary thing, the brakes very quickly become less than useless. A large vehicle has far less braking in reserve than a car, not helped by the trend towards smaller wheels for low entry.
Plus of course, we are talking airbrakes here. Yes, they have a spring assist if you run out of air (that's basically the parking brake), but it is feeble to say the least. Actual braking depends on pressure in the cylinders.
Once the brakes have faded, you may as well be driving a bobsled. Putting it into N won't help, because how are you going to stop it? The only way to slow down is to scrape something solid or as this chap did, drive into something soft. His decision was no doubt influenced by the pedestrian crossing a few metres ahead of where he ditched the bus, at that time of day there will have been stopped cars and people on the crossing?

 

[lightning76]

Could it have been something in the engine bay, rather than a problem with the accelerator pedal itself?

This makes an interesting read - from Rob Haywood's site about his time with Leicester City Transport. He was later a bus driver in Hull, which also had Metro-Scanias.
Under 'photo 14' about the Metro-Scania:

Buses : Leicester City Transport

memories of leicester city transport and its buses

www.rhaywood.karoo.net

Another Metro-Scania (a London Transport one) famously ended up in Clapton Pond.

"Power surges" do happen, I've experienced probably 3 or 4 in my 27 years on the buses, all on Dennis Darts / Tridents. I have to say none were quite as dramatic as the incident quoted, but they certainly can and do happen and are extremely disconcerting.

However from the information posted on this thread, I wouldn't expect that to be the cause in this case.

 

[Zamracene749]

Edit- also- it wouldn't need to be throttle failure. Diesel engines can suffer from turbocharger oil seal failure. When this happens, the engine will run away on full power burning the lubricating oil.Nothing can then stop it until the sump oil runs out or it explodes/seizes.
I'm simply throwing in a few factors that might exonerate the driver?

== Doublepost prevention - post automatically merged: Today at 21:31 ==

"Power surges" do happen, I've experienced probably 3 or 4 in my 27 years on the buses, all on Dennis Darts / Tridents. I have to say none were quite as dramatic as the incident quoted, but they certainly can and do happen and are extremely disconcerting.

However from the information posted on this thread, I wouldn't expect that to be the cause in this case.

Quoted from the guardian after the fatal accident in Sunderland, 1998.
'The history of unexpected power surges or unintentional acceleration had been known to Dennis for more than a decade with separate reports from the Motor Industry Research Association, the Cranfield research institute and an ergonomics company all highlighting the problem. The company said that design improvements had been made after the Mira and Cranfield reports in the early 1990s, but acknowledged that incidents continued until the Sunderland tragedy.'
The driver involved in that one, reknowned as being careful, came to a sad end after being made the scapegoat, despite the courts clearing him.

 

[Towers]

Edit- also- it wouldn't need to be throttle failure. Diesel engines can suffer from turbocharger oil seal failure. When this happens, the engine will run away on full power burning the lubricating oil.Nothing can then stop it until the sump oil runs out or it explodes/seizes.
I'm simply throwing in a few factors that might exonerate the driver?

An engine burning its oil in that manner is, of course, immediately identifiable owing to the dense, dark smoke that it will create.

 

[Leyland Bus]

Edit- also- it wouldn't need to be throttle failure. Diesel engines can suffer from turbocharger oil seal failure. When this happens, the engine will run away on full power burning the lubricating oil.Nothing can then stop it until the sump oil runs out or it explodes/seizes.
I'm simply throwing in a few factors that might exonerate the driver?

== Doublepost prevention - post automatically merged: Today at 21:31 ==


Quoted from the guardian after the fatal accident in Sunderland, 1998.
'The history of unexpected power surges or unintentional acceleration had been known to Dennis for more than a decade with separate reports from the Motor Industry Research Association, the Cranfield research institute and an ergonomics company all highlighting the problem. The company said that design improvements had been made after the Mira and Cranfield reports in the early 1990s, but acknowledged that incidents continued until the Sunderland tragedy.'
The driver involved in that one, reknowned as being careful, came to a sad end after being made the scapegoat, despite the courts clearing him.

I thought about the turbo drinking oil but having witnessed that happening first hand on a B10BLE in a bus garage, the smoke emitted is horrific, it filled an entire depot in minutes with thick acrid smoke, there was no sign of that on any of the videos.

Also, all the talk of "just drop it into neutral" is nonsense. The main thought will be about keeping control and probably not letting panic take over. It would likely have all felt like a split second for the driver, its far too easy to suggest this stuff when you're not the one behind the wheel...

 

[TRAX]

Of course brakes on a bus work in a matter of fail safe so require air to release them so any leak would bring them on.

Only the parking brake.

 

[Howardh]

If a passenger is aware the bus may crash, I wonder what the best position would be in order to receive lesser injuries - we know of the "brace" position inside aircraft, but that would be with a seatbelt on. In the case of a bus, would it be best to take the brace position, cover head with arms and try to force yourself onto the back of the seat in front; thus avoiding whiplash on impact? Or turn your back to the seat in front? Of course there are other issues which could include flying glass, bags etc in which case it's probably pure luck.