I have experienced aqua planning  while doing 100 mph on the M6 in medium traffic in the UK.   I was a very newly licenced driver and thought I knew it all.    It put the fear of Christ into me.  I have also driven a lot in snow and Ice conditions and lost control at slow speed.    This was due to my poor driving skills at the time. I actually caused  the aqua planning by not driving to the conditions. I was  racing to catch up to a friend in  not so heavy rain   got close behind him  (smart a*se) and touched the brake. 

I use Cruise control a lot on long journeys towing, and in town driving where it reasonable to do so.   You have to drive your Rig to the conditions  prevailing at the time.

The warning above is a bit of a Furphy that keeps doing the rounds.   Like the man/woman  (Polack, Paddy, Kiwi, Newfie, Tasmanian)  who put the new RV into Cruise Control and went to make coffee in the back.   Then sued  Winnebago wanting Compo.

  Cruise control has no Idea what your speed is.   It works on the RPM of the output shaft from the Gearbox. When you press the SET button it remembers what that RPM is and maintains engine revs to keep  that shaft turning at those revs   + or -   a few revs difference either side of the SET point. 

The unit maintains those RPM  that keeps the vehicle doing the speed You want. Your choice.

Any major alteration  (like wheel spin)  up or down to those set RPM and the controller  cancels itself.    This probably happens faster than you could react  to a situation and,  get your foot off the accelerator pedal without cruise control  on.

In the end It's the drivers responsibility to drive the vehicle  to the conditions at the time. 

E.G   Going into a  bend too fast  in wet weather or dry is the same  for Cruise Control or manual control   you have to slow down.

If the concept of crashes wasn't serious the whole post would be funny.

"lose traction on one wheel & the car accelerates & takes off like an aeroplane"  Indeed.  A bit late for April Fool jokes. 

I wonder why aircraft have big engines....just toss some water on the runway & engage cruise control & up up & away! 

What does that pic have to do with the story?  Doesn't even look to be a wet day.

"Don't use cruise when towing".  Why the heck not?  I, and many others do it when conditions are suitable.  Never made me run into a tree airborne.

Gave me a laugh for today anyway. 

The old idea of cruise controls was to screw up the fast idle knob.  Bit different these days as Landfall suggests.  If the computer detects a wheel increasing speed it will actually slow the engine to try to maintain speed not suddenly accelerate.

Duh wrote:

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This is true, however the story about the 36 y/o started circulating in 2002 with Texas USA as the location.  See;

http://www.snopes.com/autos/techno/wetroad.asp 

This does not diminish the fact that we should all be aware of this.

Thanks for the warning BG and also Gerty about the towing tip.

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 You are correct Duh. Usually I check on Snopes before posting information such as this, however as you say it is a fact we should all be aware of...

This is what hoax slayer has to say about the subject, quoting some other sources;

Detailed Analysis
This email forward warns that drivers should not use cruise control in the rain. The message claims that using cruise control can actually cause the vehicle to accelerate through the air if it hits standing water and hydroplanes (aquaplanes).

While the core claim (don't use cruise control in wet conditions) is valid, the message seriously mangles the facts and is therefore misleading and overly alarmist.

©iStockphoto.com/budgetstockphoto An emailed warning about using cruise control in the wet contains elements of truth but is otherwise misleading and inaccurate

Certainly, using your vehicle's cruise control in wet or icy conditions can be dangerous - but not for the reasons outlined in this warning message. It almost goes without saying that aquaplaning can occur regardless of whether cruise control is engaged or not. Aquaplaning occurs when a tyre's grooves cannot remove water quickly enough and the tyre therefore loses contact with the road surface and skims across the top of the standing water. Car accidents often happen as a result of aquaplaning, but in many cases this is due to poorly maintained vehicles, driver inattention or poor road conditions and has nothing at all to do with cruise control.

That said, if cruise control is engaged when aquaplaning occurs, the driver's subsequent reaction could make the encounter worse than it may have otherwise been. For example, the driver may hit the brake heavily to disengage cruise control and this could lock up the wheels completely. Furthermore, drivers often move their feet away from the pedals when cruise control is engaged and they may also be a little less attentive than normal. In an aquaplaning situation the small delay caused by these factors could equate to the difference between a safe recovery and a serious accident. Also, an inattentive driver could hit the accelerator instead of the brake to disengage cruise control, and this could of course speed up the vehicle and lead to loss of control.

However, the claim in the message that cruise control itself can actually make the vehicle accelerate and fly through the air in a hydroplaning situation is dubious at best. A CarPoint Australia article that debunks the claims in the email notes:

This is the key that makes a nonsense of the email. Modern cars take their speedo reading from the driveshaft or transmission. This means the cruise control bases its responses on the speed of the driven wheels, not the car itself. This is an important distinction and fail safe position.

If the driven wheels skid because they lose grip, the spinning wheels will cause the speedo to show a higher reading which will force the cruise control to release the throttle faster than most drivers. Regardless of whether the car itself slows down or speeds up, the cruise control will always reduce the throttle no matter what until the driven wheels slow down back to the pre-set speed.

If the wheels continue to slip under this scenario, this will always leave the car travelling more slowly relative to the road, not faster as described in the email.

This finding is confirmed by the RAA's Technical Manager Mark Borlace, who explains:

"Should the car's tyres break traction with the road, such as in an aquaplane situation, the increase in wheel speed would be sensed and the cruise control system would then reduce the amount of throttle and maintain the set speed."

"Additionally, cruise control systems are deactivated as soon as the brake is applied. As braking is usually an automatic reaction in most emergency situations, the scenario of cruise control causing an increase in vehicle speed is highly unlikely."

Thus, there is no inherent factor in the cruise control mechanism itself that could lead to a hydroplaning vehicle speeding up and flying through the air.

Like many email "warnings" there is no way of verifying if the event described in the message actually occurred or was simply added to drive home the core points. The version included here is set in Australia. However, other versions with virtually identical wording have featured US place names. Another popular version changes the location to a road between Gladewater & Kilgore, Texas. This duplication implies that, at least for later versions of the message, the perpetrator is not relating an actual incident he or she has experienced but has simply altered an existing message to fit local conditions.

The bottom line? Using cruise control in wet conditions certainly can be dangerous but it will NOT cause your vehicle to speed up and fly through the air. Engaging cruise control in any road situation that is less than optimal is ill-advised. Such road situations include not only wet and rainy conditions , but also icy roads, high traffic, poor visibility and rough, narrow, hilly or excessively bendy roads. However, do we really need an unverified and factually dubious email forward to make us aware of such factors? I would hope that not using cruise control in wet or other potentially dangerous conditions would simply be common sense for any responsible driver.

Duh wrote:

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This is what hoax slayer has to say about the subject, quoting some other sources;

Detailed Analysis
This email forward warns that drivers should not use cruise control in the rain. The message claims that using cruise control can actually cause the vehicle to accelerate through the air if it hits standing water and hydroplanes (aquaplanes).

While the core claim (don't use cruise control in wet conditions) is valid, the message seriously mangles the facts and is therefore misleading and overly alarmist.

©iStockphoto.com/budgetstockphoto An emailed warning about using cruise control in the wet contains elements of truth but is otherwise misleading and inaccurate

Certainly, using your vehicle's cruise control in wet or icy conditions can be dangerous - but not for the reasons outlined in this warning message. It almost goes without saying that aquaplaning can occur regardless of whether cruise control is engaged or not. Aquaplaning occurs when a tyre's grooves cannot remove water quickly enough and the tyre therefore loses contact with the road surface and skims across the top of the standing water. Car accidents often happen as a result of aquaplaning, but in many cases this is due to poorly maintained vehicles, driver inattention or poor road conditions and has nothing at all to do with cruise control.

That said, if cruise control is engaged when aquaplaning occurs, the driver's subsequent reaction could make the encounter worse than it may have otherwise been. For example, the driver may hit the brake heavily to disengage cruise control and this could lock up the wheels completely. Furthermore, drivers often move their feet away from the pedals when cruise control is engaged and they may also be a little less attentive than normal. In an aquaplaning situation the small delay caused by these factors could equate to the difference between a safe recovery and a serious accident. Also, an inattentive driver could hit the accelerator instead of the brake to disengage cruise control, and this could of course speed up the vehicle and lead to loss of control.

However, the claim in the message that cruise control itself can actually make the vehicle accelerate and fly through the air in a hydroplaning situation is dubious at best. A CarPoint Australia article that debunks the claims in the email notes:

This is the key that makes a nonsense of the email. Modern cars take their speedo reading from the driveshaft or transmission. This means the cruise control bases its responses on the speed of the driven wheels, not the car itself. This is an important distinction and fail safe position.

If the driven wheels skid because they lose grip, the spinning wheels will cause the speedo to show a higher reading which will force the cruise control to release the throttle faster than most drivers. Regardless of whether the car itself slows down or speeds up, the cruise control will always reduce the throttle no matter what until the driven wheels slow down back to the pre-set speed.

If the wheels continue to slip under this scenario, this will always leave the car travelling more slowly relative to the road, not faster as described in the email.

This finding is confirmed by the RAA's Technical Manager Mark Borlace, who explains:

"Should the car's tyres break traction with the road, such as in an aquaplane situation, the increase in wheel speed would be sensed and the cruise control system would then reduce the amount of throttle and maintain the set speed."

"Additionally, cruise control systems are deactivated as soon as the brake is applied. As braking is usually an automatic reaction in most emergency situations, the scenario of cruise control causing an increase in vehicle speed is highly unlikely."

Thus, there is no inherent factor in the cruise control mechanism itself that could lead to a hydroplaning vehicle speeding up and flying through the air.

Like many email "warnings" there is no way of verifying if the event described in the message actually occurred or was simply added to drive home the core points. The version included here is set in Australia. However, other versions with virtually identical wording have featured US place names. Another popular version changes the location to a road between Gladewater & Kilgore, Texas. This duplication implies that, at least for later versions of the message, the perpetrator is not relating an actual incident he or she has experienced but has simply altered an existing message to fit local conditions.

The bottom line? Using cruise control in wet conditions certainly can be dangerous but it will NOT cause your vehicle to speed up and fly through the air. Engaging cruise control in any road situation that is less than optimal is ill-advised. Such road situations include not only wet and rainy conditions , but also icy roads, high traffic, poor visibility and rough, narrow, hilly or excessively bendy roads. However, do we really need an unverified and factually dubious email forward to make us aware of such factors? I would hope that not using cruise control in wet or other potentially dangerous conditions would simply be common sense for any responsible driver.

For an in depth technical analysis of this issue, see:
Cruise Control and Aquaplaning: the facts

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 I think that is what I said but in much fewer words.