Cruise Control and MPG

BeenThroughItAll

AdrianC wrote: »

But you don't think any of those things affect the speed you might choose? You don't think that, if you're approaching traffic in front, you'd gently let your speed bleed down to the same as theirs? If the gap in front is increasing, you'd gently increase your speed to keep the gap more constant? If you might need to change lanes soon, you'd not adjust your speed so that you fit more seamlessly into a gap?

Or you'd just sit blindly cruise-controlling along at a set speed and if it doesn't quite fit the traffic flow around you, then hey-ho, that's their problem?

I don't think your assessment of my driving is in any way fair. What's to stop me doing all of those things whilst using CC? I can't understand why you equate use of CC with an inability to 'let speed bleed down', 'gently increase speed', 'adjust speed' or 'fit seamlessly into a gap'.

Having CC doesn't prevent me using the brakes, or the accelerator, or the steering, or my indicators or mirrors. Hence, I'm able to slow down, speed up, and spot gaps just as effectively as anyone else, and no, I don't 'blindly' sit disrupting the traffic flow - if anything, other traffic is disruptive to me since most people using their feet to control speed are congenitally incapable of maintaining a single speed without slowing down going uphill, speeding up going downhill, or braking heavily to cross lanes to slip roads.

Factor in the majority of myopic fools incapable of anticipating what's happening in front of them, and there are plenty of other disruptive factors.

I use CC where it is appropriate and safe to do so, and in 20 years and hundreds of thousands of miles I've been involved in the sum total of one accident when I was 17. Now I know that doesn't prove I'm a good driver, and I'm not for one second suggesting I can't learn more, but statistically speaking if I were as blinkered and unaware as you're suggesting, those nuns and kittens would all be dead by now at my hands.

I drive a car and ride a motorcycle - unlike many motorcyclists I use my bike for over 6K miles a year, and in all weathers (except ice and snow). I wouldn't survive if I were as unobservant as you seem to think using CC makes me.


From what I see every day, the drivers who have difficulty using CC are those who use it inappropriately as I say; setting too high a speed, too low a speed, or when traffic or road conditions do not lend themselves to its use.

Ultrasonic

BeenThroughItAll wrote: »

Really? On what basis can you say that with certainty?

I say it for a number of reasons, the first of which is the one which makes me say it with certainty (although by how much is debatable). I should say I am talking about basic cruise control here, radar guided CC may well be safer than standard driving.

1) If I drive normally I can start to slow down the instant I take my foot off the accelerator. Unless someone with CC drives with their foot constantly covering the brake (which is unlikely) it will take longer to start to decelerate. Having your foot on the accelerator also means that you can speed up quicker should this be helpful.

2) Through years of driving I find it much more natural to quickly move my foot from the accelerator to the break in an emergency, than I did from a resting position at the side. Although with practice this would become less of an issue.

3) As AdrianC described above, a truly constant speed is very rarely appropriate on UK motorways. When I tried cruise control, there were occasions where if I were in full control I would have eased off on the accelerator but with CC on I found myself wanting to leave it engaged and therefore kept the speed up just a little bit longer. I tried not to do this but being honest, I did.

If I were doing a long American road trip on deserted roads then I would probably use CC, but for the vast majority of UK driving I firmly believe that not using CC is safer. I'm not saying CC should be banned for being dangerous though.

BeenThroughItAll

Ultrasonic wrote: »

I say it for a number of reasons, the first of which is the one which makes me say it with certainty (although by how much is debatable). I should say I am talking about basic cruise control here, radar guided CC may well be safer than standard driving.

1) If I drive normally I can start to slow down the instant I take my foot off the accelerator. Unless someone with CC drives with their foot constantly covering the brake (which is unlikely) it will take longer to start to decelerate. Having your foot on the accelerator also means that you can speed up quicker should this be helpful.

2) Through years of driving I find it much more natural to quickly move my foot from the accelerator to the break in an emergency, than I did from a resting position at the side. Although with practice this would become less of an issue.

3) As AdrianC described above, a truly constant speed is very rarely appropriate on UK motorways. When I tried cruise control, there were occasions where if I were in full control I would have eased off on the accelerator but with CC on I found myself wanting to leave it engaged and therefore kept the speed up just a little bit longer. I tried not to do this but being honest, I did.

If I were doing a long American road trip on deserted roads then I would probably use CC, but for the vast majority of UK driving I firmly believe that not using CC is safer. I'm not saying CC should be banned for being dangerous though.

I'm sure there's been a thread about this already recently.


I accept your third point to some extent, but I use CC a lot and being able to find a safe constant speed is dependent upon the level of traffic and the type of road. On most dual carriageways and motorways, it's possible to find a speed between 50-75MPH which can be set as a constant without causing problems to other drivers (lower limit here would only be used in slow moving sections, I wouldn't advocate travelling at below 60MPH on a DC or MWay under normal circumstances as a result of risk of obstructing limited LGVs).


With regard to the first point, being able to decelerate, I can just hit 'cancel' on the steering wheel or lightly tap the brake to slow down (even if I don't continue using the brakes and just coast to slow down). In fact, there's only one action associated with the latter - my foot goes straight to the brake pedal from rest in one motion, rather than lifting off the accelerator, moving to the left, then depressing the brake pedal as I would had I been on the throttle manually.


I can't comment on the second point. I don't find it takes me more than a fraction of a second to move from resting position at the right hand side of the accelerator pedal to the brake pedal. I'd normally hit 'cancel' at the same time, so I'm confident in an emergency situation it wouldn't take me any longer to stop from CC engaged than from 'normal' manual control.

Herzlos

Ultrasonic wrote: »

1) If I drive normally I can start to slow down the instant I take my foot off the accelerator. Unless someone with CC drives with their foot constantly covering the brake (which is unlikely) it will take longer to start to decelerate. Having your foot on the accelerator also means that you can speed up quicker should this be helpful.

The speed up/down dial and cancel buttons can be hit with my thumb from a comfortable driving position, I can "ease off" just as quickly as you can. Hitting any of the petals also overrides the CC.

2) Through years of driving I find it much more natural to quickly move my foot from the accelerator to the break in an emergency, than I did from a resting position at the side. Although with practice this would become less of an issue.

I agree with this point; but then I normally have plenty of time to cover the brake when I think it might be needed. I certainly rarely drive with my feet out of the way.

Have you used CC recently? I had it on a 1992 Dodge and it was awful, but then so was the car. The 3 versions I've used more recently have been a lot better.

AdrianC

Herzlos wrote: »

The speed up/down dial and cancel buttons can be hit with my thumb from a comfortable driving position, I can "ease off" just as quickly as you can. Hitting any of the petals also overrides the CC.

OK, great - so you're constantly adjusting your speed to suit the surroundings.

So, umm, what's the point of putting the cruise on?

Herzlos

AdrianC wrote: »

OK, great - so you're constantly adjusting your speed to suit the surroundings.

So, umm, what's the point of putting the cruise on?

Not really, I can sit for over an hour without adjusting settings*, and then tweak them or disengage as I see traffic or anything I need to alter speed for up ahead.

*I tend to only use it on comparatively motorways, like the M6/74 between Manchester & Glasgow, M9 North of Edinburgh and so on, where I can potentially see no other cars in either direction for long periods of time.

DUTR

AdrianC wrote: »

OK, great - so you're constantly adjusting your speed to suit the surroundings.

So, umm, what's the point of putting the cruise on?

Have a look at this .

Trebor16

Ultrasonic wrote: »

My Octavia has cruise control but I don't use it. Primarily because it is safer not to but also because I get slightly better fuel economy with my right foot. The latter is essentially because I can look ahead and anticipate what I may want to do with the accelerator but CC can't.

You can look ahead and anticipate with CC too. When you think you need to slow down you just deactivate it. Simples.

getmore4less

AdrianC wrote: »

It depends on the traffic conditions.



Specsheet kudos, mostly...



But you don't think any of those things affect the speed you might choose? You don't think that, if you're approaching traffic in front, you'd gently let your speed bleed down to the same as theirs? If the gap in front is increasing, you'd gently increase your speed to keep the gap more constant? If you might need to change lanes soon, you'd not adjust your speed so that you fit more seamlessly into a gap?

Or you'd just sit blindly cruise-controlling along at a set speed and if it doesn't quite fit the traffic flow around you, then hey-ho, that's their problem?

Don't forget the alternative senario...

if you are about the right speed people start to fit around you as CC cars adjust to each other......

Then you get a convoy.....


(guessing not many get the reference)

Ultrasonic

BeenThroughItAll wrote: »

I'm sure there's been a thread about this already recently.

Quite possibly, I haven't posted here for ages.

BeenThroughItAll wrote:

With regard to the first point, being able to decelerate, I can just hit 'cancel' on the steering wheel or lightly tap the brake to slow down (even if I don't continue using the brakes and just coast to slow down).

Yes, sure you can, but it takes longer to move your hand to a control than it does to move a foot already on the accelerator. Plus the point that as soon as you start to move your foot the car will decelerate due to easing off of the accelerator.

BeenThroughItAll wrote:

In fact, there's only one action associated with the latter - my foot goes straight to the brake pedal from rest in one motion, rather than lifting off the accelerator, moving to the left, then depressing the brake pedal as I would had I been on the throttle manually.

My argument would be that your foot needs to move from further away and from a more relaxed state and is therefore bound to take longer to hit the brake than with 'normal' driving.

BeenThroughItAll wrote:

I can't comment on the second point. I don't find it takes me more than a fraction of a second to move from resting position at the right hand side of the accelerator pedal to the brake pedal. I'd normally hit 'cancel' at the same time, so I'm confident in an emergency situation it wouldn't take me any longer to stop from CC engaged than from 'normal' manual control.

I don't suppose you would, but doing anything with your hands other than concentrating on steering during an emergency braking situation sounds like a bad idea to me. Presumably hitting the break will have the effect of canceling the CC.

Just to reiterate, I'm not saying using CC is dangerous, but I do believe that not doing so is safer.