Scary aquaplaning - be careful in the wet (esp with RWD!)
Discussion
Well, I certainly feel a bit shaken tonight - I was driving at 70 in my Z4MC on the outside lane of the M25, around junction 5 this evening and hit a puddle... I massively aquaplaned and lost the rear-end. The first move was a veer left, and i'd say the nose probably deflected around 50-60 degrees from the direction of travel. I steered against, and then pendulumed probaly 3 full times back and forth (ever decreasingly) until regaining control. I think i have the DSC to thank for bringing her back into line, even though it took a few swings, the light was blinking throughout.
Easily the scariest thing in my driving life. Thankfully there was no-one near me and it ended safely for all...but it's made me re-evaluate my driving in the wet. I think i would even have lost the car at 60 in that puddle so im not sure what one should do...it wasnt raining torrentially, but it had been a medium-heavy rain for a while.
Has anyone else experienced anything like that? Is the problem worse in RWD cars with wide tires? is it a Z4 thing? when I slowed down after the incident I was amazed at the people zooming past, oblivous (from my vantage point in the slow lane!)
Thanks
Easily the scariest thing in my driving life. Thankfully there was no-one near me and it ended safely for all...but it's made me re-evaluate my driving in the wet. I think i would even have lost the car at 60 in that puddle so im not sure what one should do...it wasnt raining torrentially, but it had been a medium-heavy rain for a while.
Has anyone else experienced anything like that? Is the problem worse in RWD cars with wide tires? is it a Z4 thing? when I slowed down after the incident I was amazed at the people zooming past, oblivous (from my vantage point in the slow lane!)
Thanks
I had a similar experience in my RX8 a few weeks a go but didn't sound as bad as yours. Wide tyres certainly don't help, not sure about RWD though because surely even a 4WD car would loose contact with the surface after initial contact with the water. I guess it might be a factor once the car has lost control though.
I think it is the wide tyres rather than run-flats.
I have had a similar experience with 'normal' but very wide tyres in slushy snow conditions on the motorway, but only doing about 40mph.
Very scary when it happens, and thankfully, like the OP, after two or three swings either way, got the car pointing back in the right direction without hitting anything.
I have had a similar experience with 'normal' but very wide tyres in slushy snow conditions on the motorway, but only doing about 40mph.
Very scary when it happens, and thankfully, like the OP, after two or three swings either way, got the car pointing back in the right direction without hitting anything.
I have been fortunate enough to do an aquaplaning exercise on a driving course, and it made the biggest impact of the whole day.
We had to corner at about 70mph, near grip limit, dsc off, then the instructor dampened a small part of the curve without telling us.
As the OP experienced, the car dived violently off to the outside of the corner. Instinctively, you wind on more lock, but as the tyres regain dry tarmac, you get pitched into terminal oversteer (or you use up a lot of space fighting the pendulum).
The solution, was to wind-off steering lock, so that when the car returns to dry tarmac, the wheels are pointing straight, and only then steer back onto course.
This is extremely counter-intuitive, but does work.
We had to corner at about 70mph, near grip limit, dsc off, then the instructor dampened a small part of the curve without telling us.
As the OP experienced, the car dived violently off to the outside of the corner. Instinctively, you wind on more lock, but as the tyres regain dry tarmac, you get pitched into terminal oversteer (or you use up a lot of space fighting the pendulum).
The solution, was to wind-off steering lock, so that when the car returns to dry tarmac, the wheels are pointing straight, and only then steer back onto course.
This is extremely counter-intuitive, but does work.
Hey All,
Thanks for your replies.
They are not runflats, they are Continental sport contact (255/40), treads seem in good condition. Had the car for about 4k miles since I picked it up last december from BMW Approved Used.
'drive to the conditions'. It's obvious and I couldn't agree more. Funny thing is I thought I was being prudent, with big forward separation. This will sound dumb but I hadn't even considered a puddle on a motorway...I have only encountered one once before and that was during a torrential downpour in 2006 when everyone had dropped to about 30mph. In summary, please, everyone, just be safe in the wet! Like I said, after my incident I was a chronic spectator to ford focuses and minivans zooming past..at 70+
Thanks for your replies.
They are not runflats, they are Continental sport contact (255/40), treads seem in good condition. Had the car for about 4k miles since I picked it up last december from BMW Approved Used.
'drive to the conditions'. It's obvious and I couldn't agree more. Funny thing is I thought I was being prudent, with big forward separation. This will sound dumb but I hadn't even considered a puddle on a motorway...I have only encountered one once before and that was during a torrential downpour in 2006 when everyone had dropped to about 30mph. In summary, please, everyone, just be safe in the wet! Like I said, after my incident I was a chronic spectator to ford focuses and minivans zooming past..at 70+
Not a nice feeling at all, my old 2wd cossie used to spin up regular in the wet, 4th gear some times, not quite aquaplaning i no but still that waxing with the steering wheel moment, i got caught out a couple of times but as said above i changed my driving to suit the conditions too
Be carefull is the only tip
Be carefull is the only tip
Ah, Conti CS2s. I have always hated those tyres (and the CS1s) for their propensity to aquaplane. I had CS1s on my first M3 and CS2s as OEM fit on the M5. When the first M3 was stolen, the new one had PS1s and when the CS2s on the rear of the M5 wore, I switched to PS2s. In each case, the feeling of dread in very wet conditions receded as a result.
yep wrote my first Z4MC off doing exactly the same thing on the motorway, the main difference was i or the DSC didn't save it and i ended up hitting the nearside armco 3 times! ouch!
anyway lesson learned, if theres standing water i drive much slower than i used to... you can still get a good twitch on even at 45mph if the water deep enough!
anyway lesson learned, if theres standing water i drive much slower than i used to... you can still get a good twitch on even at 45mph if the water deep enough!
If you have a powerful car with wide tyres then heavy rain demands extreme caution. I was driving the Z3 yesterday on a dual carriageway in very heavy rain with lots of visible standing water, and 50mph felt too fast in places.
As far as aquaplaning goes, I'm not sure that DSC is any help directly. Unless you are fortunate, you often just proceed to the scene of the accident if the car snaps sideways - no grip at all! DSC is no help if your tyres are not in contact with the road surface!
As far as aquaplaning goes, I'm not sure that DSC is any help directly. Unless you are fortunate, you often just proceed to the scene of the accident if the car snaps sideways - no grip at all! DSC is no help if your tyres are not in contact with the road surface!
Gassing Station | M Power | Top of Page | What's New | My Stuff