Hi

I received the following in an email.

Cruise control saftey

NEVER KNEW THIS BEFORE

I wonder how many people know about this?

A 36-year-old female had an accident several weeks ago and totalled her car. A resident of Wollongong, NSW, she was travelling between Wollongong & Sydney. It was raining, though not excessively, when her car suddenly began to hydroplane and literally flew through the air.

She was not seriously injured but very stunned at the sudden occurrence!

When she explained to the policeman what had happened, he told her something that every driver should know - NEVER DRIVE IN THE RAIN WITH YOUR CRUISE CONTROL ON. She had thought she was being cautious by setting the cruise control and maintaining a safe consistent speed in the rain. But the policeman told her that if the cruise control is on and your car begins to hydroplane -- when your tyres lose contact with the pavement, your car will accelerate to a higher rate of speed and you take off like an airplane. She told the policeman that was exactly what had occurred.

The policeman estimated her car was actually travelling through the air at 10 to 15 kph per hour faster than the speed set on the cruise control. The policeman said this warning should be listed, on the driver's seat sun-visor - NEVER USE THE CRUISE CONTROL WHEN THE PAVEMENT IS WET OR ICY, along with the airbag warning. We tell our teenagers to set the cruise control and drive a safe speed - but we don't tell them to use the cruise control only when the road is dry.

The only person the accident victim found, who knew this (besides the policeman), was a man who had had a similar accident, totalled his car and sustained severe injuries. If you send this to 15 people and only one of them doesn't know about this, then it was all worth it. You might have saved a life

What I think

If your doing a set speed with the cruise control on and the wheels started spinning the cruise control would sense that your car has gone over the set speed and back off.

Maybe the driver was doing a low speed and used the resume feature to go back to a previously set speed, say the car was doing around 80kph and the set speed was 110 kph, that would be just like massing the accelerator pedal to the floor in slippery conditions.

Steve

In our Dunnydore, with the cruise on, and aquaplaning, the traction control cancels the cruise control. It did it several times on the dual carriageway between Karuah and Raymond Terrace. Freaked me out 1st time.

I doubt vehicles fitteed with cruise AND traction control would suffer with that problem.

have not heard of this before but it would be possible for the cruise control to make it dangerous... dont know about the "flying through the air" bit though...

can't see it. The speedo sensor suppies the signal to the cruise control. Therefore, cruise control couldn't allow the car to accelerate to a higher speed than it is set at. Even with wheel spin, only one wheel will spin faster in an open diff type situation. As far as I can see this is just a myth. And i've used cruise control in the rain. Seemed fine.

"But the policeman told her that if the cruise control is on and your car begins to hydroplane -- when your tyres lose contact with the pavement, your car will accelerate to a higher rate of speed and you take off like an airplane."

OK, aquaplaning does not give your car lift in order to allow it to fly like a plane. That's not what aquaPLANING means. Aquaplaning means your tyres are suddenly riding on a cussion of water instead of the road surface.

As for the car being able to accelerate after it's tyres lose contact with the road? Who came up with that load of dribble? I think you'll find you need TRACTION to be able to accelerate in ANY car, cruise control or not...

That said, don't use cruise control on older cars in the rain. Cruise control tries to keep your car at a preset speed, accelerating and decelerating with no regard for how wet and dangerous the road is, or what sort of road surface you are on.

no, its all just another bullshit chain letter. if that actually happened, wouldn't we have heard about it? And dont tell me that only two people have used their cruise control in the wet before, that is simply rediculous.

IT IS TRUE.

A mate of mine brought a Ford XR8 brand new and it was written off with less than a 1000km on it.

He was driving with the cruise control on at 100km on an outback highway

The road was a bit up and down anyway and while going around a slight bend the car hit a wet patch, back end lost grip and the car started to oversteer.

He asumed the car would soon snap back in line but instead the cruise control increased the throttle to maintain the speed and the car ended rolling several times.

No serious injuries but it all sounds logical.

The cruise control module has the speed sensor as its only imput as what to do and controls the throttle only according the the speed sensor.

The only other things which disengage the cruise control is the brakes and somtimes the clutch or gearlever. The cruise control module wouldn't know if the car was upside down in a ditch or driving along happily.

I am unsure what vehicle with traction control would do in a similar situation



Jeremy

[ Edited on 4-4-2006 by jeremy ]

this is exactly the same as the needles in the chairs, diet coke causes cancer, msn is shutting down, stupid stupid chain letters that get passed around.

msn will not shut down, it makes too much money.
if there were needles in chairs at movie theatres, wouldnt the tv or magazines have something about it?
Diet coke does not cause cancer, and if you have cancer and stop drinking diet coke, your cancer will not go away.
and if you send this chain letter to 7 people in 7 minutes, your high school crush will call you at midnight, you will win the lottery, and bill gates will donate 5 cents to a homeless starving ethiopian.

boring. heard it all before.

i can see the logis on the last couple of posts, but surely the 1 wheel that is spinning (or 2 if LSD) at the rear, because they are free spinning (ie no friction from the road) they are needing very little power to turn them , so although they are spinning faster, they are using less throttle to spin them then the car was using previously on dry, and therefore when it does come out of the wet and bites the road, the tyres will come very quickly back to the slower speed as there is not enough power from the engine to maintain their speed. this could cause a heck of a momuntary jolt. unfortunately, this whole concept is based on the speedo being driven off a wheel independant of the drivechain. as far as i know many if not most-all modern cars run their speedos from gearboxes or driveshafts, or diffs, or possibly in the case of FWD cars, possibly the driven wheels, in any of these cases the speed being registered by the speedo would be relative to the speed of the driven wheels in which case the worst case scenario would be that the car had slowed down through the water but the wheels were still spinning at the set speed.

Yes, but you can't combat urban myths with logic. There's always someone who knows a guy who knows a guy who....

the flying through the air is absolute nonsense (unless she hit an embankment or curb)...

BUT...

Its true that you if you are on cruise control, and you aquaplane, the wheels momentarily accelerate and on returning to the bitumen, CAN and most likely WILL cause sudden violent acceleration.... and since you've been aquaplaning, this will probably happen in a direction you don't want to go!

However, this mostly applies to older types of cruise control that were virtually a clamp holding the throttle cable for you... modern cruise controls are an eeeency bit better, but if the conditions are that bad, then you should probably be driving the car yourself, and not relying on cruise control to "keep you safe".

[ Edited on 4-4-2006 by fekkinell ]

This one's been floating around now for about six weeks thru e-mails everywhere and I think we all gave a good technical explanation outside the forum that it was all "BS".

Maybe both driver AND copper was blonde to think the car would accelerate by the amount stated!

Makes no sense to me? Our Beetle certainly has no cruise control.

My Magna has factory cruise control and it Aquaplaned once whilst on Cruise, but it didn't seem to affect it.
-Staggers.

See http://www.snopes.com/autos/techno/wetroad.asp  - same story only in Texas.

http://www.snopes.com  is a great site for debunking urban myths, but in this case it says it is TRUE. I notice that a few words have been added about flying through the air in the Oz version.

I think this may have been true of older cruise control (except for the flying bit), but newer cars have it tied in to traction control and anti-lock brakes and the like.

---------------------------------------------------------------------------------

Yeah, older cars with a servo unit and cable setup perhaps?
-Staggers.

Plus, the car doesn't take off, it only feels that way because of the floating effect on water. If this was all true, it would also be the same when you're not using CC (Reduced load=Increased RPM at the same accelerator position).
-Staggers.

what a load of bullshit

Yeah BS IMHO

I think it's all crap!
-Staggers.

Hi

OK, so myth busted? Or do you need a big red moustache to say that?

I’m a cruise control junky, I useit to go down the shops, I even fitted it to my old yellow bug and I will refit it to my new bug, all in the interest of keeping points on my licence. What really gives me the dirts is with all the 40-kph school zones around, why can’t I use the cruise on my Prado or Falcon ute to keep to the school zone speed, if drop below 40 it cuts out.

Steve

hehe..that my friend... is for the simple reason that Prado's and Falcon's blow!

I can easily live without it myself... my mums VR has it and it honestly feels like more effort toggling CC than it is to slightly raise or lower the foot a little... just my take on it.

Oh... and yes,yes!..you DO indeed need the big moustache.

phenylenaline can cause a chemical reaction if the person using it is extremely allergic to to it, which may sometimes in a blue moon lead to cancer.

but if you are alergic to it, why are you drinking it in the first place?
if you're allergic to peanuts you sure as hell wouldnt eat them.

mmm..peanuts!

From what I understood phenylalinine had kind of cumulative effects... so average joe who has the occasional diet coke cos there is no normal stuff in the machine doesnt get noticably affected (unless as you said..they are allegic)... however those who drink or otherwise consume products containing Aspartame or phenylalinine on a regular basis will eventually if given long enough.... allergy or nay... develop symptoms not unlike those experienced by a patient in the early stages of MS.... :duh:

The dangers of aspartame and more specifically phenylalinine have been known to science since as far back as the early 80's....however as the majority of the worlds "diet" products contain these chemicals... welll..needless to say the information has been kept under a big-ass hat for a long time indeed...

and did you know that smoking prevents parkinsons disease?
masturbating makes u blind?
eating too much veges makes u fat?

Yeah and ABS makes you crash...

BS for quite a few mechanical reasons (but I couldn't be bothered typing) but flying through the air is what what aquaplaning FEELs like, cruise or not...

flying through the air "bullshit" none of you have ever driven the old valiant hemi pacer then:P

agh, so thats why its getting harder and harder to type...