Safe Speed Forums

Ok this one happened to me a long time ago, but it taught me more about driving in 30 seconds than I ever learnt for my L-test, so it’s probably worth sharing.

I’m helping my ex-flatmate to move house, so we’re three-up, plus a load of luggage, in a 1-litre Polo with no ABS, doing about 80 in Lane 2 of a free-flowing A1(M) out of London, overtaking slower stuff in Lane 1. I honestly can’t remember what happened next, but I must have looked down for a second, whether to check my speedo, change radio stations, or maybe I just wasn’t paying enough attention. Either way, I look up, and the Rover in front of me is suddenly near-stationary, and I’m still doing 80

I slam on the anchors and lock up immediately, and it’s obvious I’m not going to scrub off enough speed before getting intimate with the rear of the car in front. I try to swerve, but because I’m all locked up I’ve got no steering control. Luckily I remember reading something about cadence braking, and start pumping the middle pedal like crazy, which gives me just enough control to move into L3, which is fortunately empty, to get around the Rover. Still moving pretty quickly, with smoke billowing from the wheels, I find myself face-to-face with a large piece of debris between Lanes 2 & 3, which was presumably the reason for everyone’s sudden braking. More pumping of the pedal and I manage to veer towards the central reservation and squeeze past it. I eventually get the car back under control without hitting anything, and drive to the nearest service station to change my underpants.

I am to this day ashamed that I was probably driving too fast and/or too close, and evidently wasn’t paying enough attention. I am however, pretty chuffed that I managed to use the cadence braking technique to retain steering control under emergency braking, and had enough wits about me not to just stamp on the middle pedal, close my eyes and hope for the best.

Lesson learnt: fail to leave a decent gap, or let your concentration drift for even a second, and you could be in deep sh*t. I find it useful to remind myself of this one as a wake-up call on long motorway journeys.

Lesson 2: When it all goes pear-shaped don't stop driving the car, and in particular don't stop steering.

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hmm, fully loaded 1L polo... 80mph. Yup, I guess so.


well you used a braking technique, and it worked so well done but you might just want to refine it just a little bit (unless you've got something with abs now). When you do it properly you slightly flex your foot on the pedal, just enough so the wheels lock/unlock almost instantaneously. Easy to say, easy enough to do when you're practising. Bloody difficult when you're about to slam into something. So best to avoid having to do it in the first place.

What you're describing is a manual version of ABS. Cadence braking is actually setting up a resonance with the suspension giving seriously high transient weight on the front axle when the brake pedal is down. If you get this perfect, once the resonance is in train (after 2 - 3 pumps) the whjeels don't actually lock much at all despite serious pedal pressure - with steering retained throughout. I've not done cadence braking with an ABS car, but see no reason not to if the circumstances demand. However, I have my doubts if to do so would give a marked improvement over a planted pedal, and it has the potential to go very wrong!

Roger,
Under no circumstance (short of ABS failure) should you try cadence braking with ABS - it's disastrous!

In my old BGT, when I'm 'pressing on a bit', I use what we used to call the 'three dab stomp' to help set the car up for corners (ie, at the commit point of the corner, three hard 'dabs' on the brake, downshift/overdrive out, feather into the corner and stomp the throttle at the point you are removing the applied lock. Correct any oversteer and upshift/overdrive in - job done).
Once (and only once!), I forgot myself whilst driving the Ayatollah's Clio on a fairly twisty back-road. Three dabs and floor it (front-wheel drive) produced total understeer as the ABS went into meltdown and a dead throttle because the ABS was overriding it - only a huge handful of 'help-handle' (handbrake) managed to discomknockerate the ABS into submission, drag the arse round and re-instate the throttle. Exiting a left-hander on the right-lock stop but still rotating left is not a recipe for clean underpants. At least the airbag didn't deploy...
When I reported this to our local Renault dealer, he assured me that I had driven the car beyond its safety design parameters. When I offered to take him along the same road in my 30 year-old MG he declined, even though I assured him that I would not exceed its 'safety design parameters' as they were down to the driver, rather than the car itself...

Modern car safety features, my ARSE!

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Aquila



Licat volare si super tergum aquila volat...

I don't understand why you would dab thrice. Isn't it better to brake progressively and feather progressively? What's the advantage of three dabs supposed to be?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Dab thrice? Dost thou doubt the eldred powers of Stig The Blomqvist and Henri The Toivenen? They too had to deal with ye 14th century cart-springs and, finding them not so lissome as ye new-fangled coil springs all round, worked out this way of dumping a lot of speed without locking up whilst entering the corner as 'flat' as possible {Roger Bacon mode cancel}.

A pursuit Jam Butty pilot called Sgt. Mick Floyd from Seaxes MC in Chelmsford came to my club in Witham and gave us a talk on 'naughty tricks' employed by the pursuit boys (late 70's/early 80's) during fast rural pursuits. This one was among them. It takes a lot of practice but, once mastered (via several 'white knuckle' moments!), is pretty effective.
Smooth and progressive is fine and dandy on the nice, wide, manicured blacktop of Goodwood, but becomes ponderous on the knackered pea-shingle-and-tar here in rural Essex.

But then, learning skills like that and applying them to the open road is probably very dangerous, as I might be inadvertantly enjoying myself! I could side-swipe a rabbit and have the ALF as well as BRAKE! hammering at my door...

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Aquila



Licat volare si super tergum aquila volat...