“There’s no such thing as bad weather, just inappropriate clothing.”
—Sir Ranulph Fiennes, polar explorer
One-fifth of our time on British roads is spent driving in wet weather, but it contributes to a third of all daytime casualties and over half of all casualties at night.
When it rains, the world changes instantly. You have to change with it. Driving technique in the rain is really no different from dry running, it just requires you to dial your reflexes in to the notion that things take longer, and the driver’s inputs need to be slower and gentler to allow the tires to cope with reduced levels of grip. Put simply, you can’t throw as much force around, and the secret to being a wet-weather ace is being silky smooth with the controls and keeping your cool.
The one element that is most different in terms of technique is the way you apply the brakes. In dry conditions, you can be assertive on the pedal and use an initial stab before you squeeze to load the front tires, and the car can accept greater forces. This doesn’t apply in wet or low-grip conditions. You have to be more gradual with the initial application to create slower weight transfers. Throttle technique is the same, but you effectively have much more power under foot than normal. Yes, sir, even you in the Cinquecento.
Locking a tire at the start of braking in the rain can cost you as much as 70 percent of your stopping power, a problem that ABS is designed to handle. Nonetheless, in the wet, as ever, skid prevention is always better than cure.
I raced an Ascari GT3 car at Mugello with none other than the boss and owner of the company, Klaas Zwart. He’s a fast driver and, by his own admission, slightly impatient.
The car didn’t make the opening practice sessions, and by the time qualifying started, Klaas’s foot was tapping a hole in the ground. As the crew fluttered around us, I insisted they cut air holes into the door for venting. Tempers frayed a touch, but I got my vents and joined one fully soaked circuit.
Forty cars churned the asphalt. Crazy people launched themselves at the track like a demolition derby, and the marshals duly counted them into the tire walls. Clouds of spray added to the downpour already challenging my one-speed windshield wiper, but the vents worked perfectly.
I picked an inside line at the end of each straight, avoiding the usual line, which was caked in glossy rubber, slipped my foot gently onto the brakes, and squeezed slowly until I felt the tire reach its limit. As the tires squirmed, the feel of grip permeated every sinew of my leg.
Walking on eggshells.
Despite walking on eggshells, when I shifted down the gears the rear wheels would occasionally lock over puddles, and the thunder of V-8 would be replaced with the deathly chatter of gearbox. I dipped the clutch and released it more slowly than a turtle swimming through molasses.
As the straight entered the curve, the rubber-coated racing line cut from the outside to the inside of the curve, so I did the opposite; I headed straight across the usual line to the outside of the bend. I released the brakes and, with no throttle, flew around the widest arc to benefit from the most unused, porous stretch of track, steering with only the lightest of touches on the wheel—feeling for a change in asphalt, and then crawling onto the throttle so carefully that I could barely hear the engine picking up.
Down the straights I sought out the shallowest puddles and splashed through dead center with the tires pointing straight, wincing as the rear tires hydroplaned and the tires spun in fifth gear, but the Ascari never wandered. By the end of the session, this tiptoeing exercise was worth pole position by one and a half seconds.
On the streets there’s nothing to be gained by using “wet” lines because the entire surface tends to be equal in terms of grip, but you can feel the change from one surface to the next. Ah, but puddle watching, what sport.
The road remains wet, and it’s the surface condition that dictates the grip level. After the rain stops the conditions linger, especially on local roads that are sheltered from sunlight. Wooded areas continue to drip water long after the surrounding roads have dried, and a nice coating of wet leaves handles like ice.
Ignore the loonies who want to tailgate in these conditions, and keep a longer distance from traffic ahead so that you can see well beyond the immediate.
You have a quarter less grip for stopping and accelerating, 50 percent less on smooth, slippery roads, and half the cornering grip of dry running.
“All that glisters is not gold . . .”
—William Shakespeare, The Merchant of Venice
During long periods of sunshine, cars lay down lots of rubber on the road surface. It becomes so highly polished by oily lubricants that it becomes less porous and reflects sunlight. The first droplets of rain sit on top of this layer and create a greasy film, which just sits there, waiting to undermine you.
In California, this happens a lot. There are ten accidents every hour in LA during peak traffic—add a little drizzle and it jumps straight to fifteen. After a long bake in the sun, our brains fail to acclimatize quickly enough just when the road is at its worst.
As soon as it rains, double your following distance. Look out for anything that shines, from manhole covers to cobblestones, and be especially mindful of regular stopping points such as traffic lights, off-ramps, bus stops, and taxi stands; they tend to get doused with slick lubricants, so leave enough stopping distance so you can feather the brake pedal for the last few yards in the wet.
“All that glisters is not gold . . .”
As rain falls, your tires work hard in a number of ways to support your progress, and their ability to do so varies considerably, as we saw in the chapter on braking.
Pressure at the tires’ leading edge cuts through the water and displaces it through the channeled grooves, yet traces of water remain. The edges of the sipes and tread blocks dig into the road surface, pressurize it, and actually break through the film of water to create dry contact.
If the water level rises on the road surface, the fronts of the tires plow through it, splitting the bow wave. Surface water is channeled away, and this process of cutting and squirting has to disperse the water quickly enough to prevent it from building up.
When the pressure of water meeting the tires’ leading edge exceeds the pressure on the contact patch, the tires lift off the road, and hydroplaning begins. You are effectively driving a boat.
Hydroplaning occurs almost exclusively at high speed, so you will experience it most on the freeway or similarly fast interstate highways. All you need to do to avoid it, therefore, is to slow down.
Heavy rain, the stuff that sounds like it’s denting the bodywork, creates perfect conditions for hydroplaning within seconds. When the road becomes saturated it forms pools in the lower portions, filling troughs and worn grooves made by trucks, and any dips by the roadside. It also creates small rivers that cross slopes in the highway with no thought for your wellbeing. Persistent rain might take a little longer to form puddles, but the point is that you need to read the conditions to anticipate the presence of standing water and moderate your speed accordingly. Don’t judge your speed by looking at other people, as their vehicles may behave entirely different from yours.
You scan the ground ahead and search for signs of standing water, which identifies itself by its shine and from the splash of incoming droplets. Noticing these signs in the daytime is hard enough with all the spray, so a healthy following distance helps. At night it becomes harder still. Usually you can make out two black stripes in your lane, which are the grooves from regular traffic filling with the deeper water.
By running slightly off the center line you can avoid the worst of it. The right lane is most affected by these grooves, the left lane less so, but the right-side shoulder may be flooded, leaving the center lane as generally the safest place to be.
Beyond these nuances, situations develop where the whole surface is covered with several inches of water. The tires become so saturated that they lift off the road.
Hydroplaning is directly proportionate to your speed, and a wide tire has to deal with a much larger flow of water. This feature has been well researched at Bugatti’s secret test track in Ehra-Lessien in Germany, where I coached Captain Slow, aka James May, on the finer points of handling a $1 million Veyron. James showcased the one thing it was designed to do best by guiding 1,000 unbroken horsepower down a five-mile straight at a speed of 253.81 mph.
The heavens opened as soon as he finished, and it looked like playtime was over, but Top Gear’s director, Nigel Simpkiss, had other ideas.
“I’d just like to get some shots of the Veyron whipping up some spray over the top of the steel barrier. Do you think that would be OK?”
The Bugatti engineer nursed his chin for an answer to this innocently couched question before consenting for us to film “a couple of runs.”
I strapped into the fitted leather throne, twisted the key, and felt sixteen pistons fizzing to life. The engineers checked the tire pressures, as they did every time the Veyron left their bosom, and I ventured out onto the gigantic highway.
I looped around a carousel and accelerated through a curve toward the straight where Nigel’s camera team was stationed by the twelve-foot barriers to my right. Even at 60 mph the rooster tail of spray was kicking pretty high, but more is an ever popular adjective in the film game, so I squeezed.
The bony feeling you get from the Bug on a dry road makes it handle like it’s on the proverbial train tracks. It sits on rubbers that are nearly fifteen inches across, making them the broadest tires ever manufactured. Throw in the four-wheel-drive and untold electronic stability systems, and you might be excused for taking a nap on the way to the yacht. So I squeezed the gas.
The 8-liter engine promptly replied, and I surged forward into a sea of shiny black asphalt, and a world of pain. All that tight handling evaporated the moment the water crawled under those fat tires. The Bug flicked sideways, and I found myself facing left toward a welcoming grass bank. They say it takes years to build a reputation but you can throw it away in a single moment. This was one of them.
The opposite lock went in immediately in an attempt to correct the extreme angle, or yaw, as pilots refer to it. Things seemed to be OK, but at nearly 2,200 pounds the Bug was projecting itself into yet deeper waters. I could feel the steering going even lighter, so I pressed the middle pedal to request a little customer service.
The ABS was thus engaged. It could perform the one task I could not, which was to activate individual braking mechanisms on each of the four tires and by doing so begin the process of addressing the slide sideways.
By adjusting individual wheel speeds and compensating for the tire that was struggling most, the ABS trimmed out enough of my rate of yaw to keep me from spinning. The speed slowly but surely bled off. Once the tires landed, the Bug snapped back into line, and because I had only applied a modest level of counter-steering I could straighten it quickly; and the nightmare was over.
The nightmare was over.
Nigel crackled over the radio: “Could we get another one of those from a different angle?”
I took the car back to pit lane, pronto.
I mentioned my little moment to the Bugatti engineer, who exhaled and explained that they had lost three Veyrons up the grass bank previously during heavy rain. We agreed we should wait for the track to drain.
Hydroplaning in a straight line manifests as a tug at the steering wheel, a braking sensation, and the sound of water gushing inside the wheel arches. One side of the car might suddenly pull more than the other. If you are accelerating at the time you might hear the engine note rising unexpectedly, as if you pressed the clutch by mistake. That sound is the driven wheels spinning!
“You recover control by effectively doing nothing.”
Serious hydroplaning only happens at speeds above 50 mph, so speed is what you need to reduce; but do it carefully.
Lift off the gas.
Keep the steering straight and grip it firmly.
Stay off all the pedals. The force of water hitting the tires acts as a natural brake, and once the speed bleeds off, the tires will touch down again. You recover control by effectively doing nothing.
When a car hydroplanes in a straight line, I personally prefer not to brake, even with ABS, because it gets confused and drags things out by locking the tires, albeit slightly, and reducing steering power. I prefer to keep some steering in reserve in case it’s required.
Hydroplaning in a curve is a different animal. The car becomes possessed, instantly losing steering and then pitching violently sideways as the tires lift off unevenly, and all this while your ejector seat is still being serviced.
If you do go sideways on standing water and you have ABS, this is the time to use it. Push hard and fast on the brake pedal, fix your steely-eyed gaze on where you would like to go, and put in the requisite opposite lock.
How much you drift across the highway will depend on your speed. Once you slow and the tires land, locate the nearest service station and dislodge excrement.
If you see a flooded curve coming at the last moment, dab the brakes and try to straighten the steering a little so the tire can plow better.
Near biblical volumes of rain have been turning our towns into Venetian piazzas. There’s a temptation to battle the elements. Deep inside, we let rip a silent but deadly Mel Gibson war cry, “Freeeeedddoommm,” and within seconds the objections of our spouse are drowned out beneath two feet of water.
I was sizing up a flooded road last month when a rare moment of Bear Grylls–worthy self-preservation gripped me. I waded into the water up to my knees to measure the depth, crucially above the height of my car’s radiator, and agreed with another driver it was a no-go. A third man thought better of it.
He reversed his newish Audi Q7 a considerable distance back up the hill, stopped, then gunned it toward the water. He must have hit it at about 50, the equivalent of slamming into a brick wall, judging by the way the hood exploded skyward. There was an impressive amount of steam from both engine and driver as he realized the reason the motor died on impact was that the water had taken out the radiator, then been sucked up the air intake. Mucho expensivo.
Avoid floodwater wherever possible, but if you give it a go . . .
