Limit points - at night!

[Slink_Pink]

I tried some limit pointing on a particularly twisty section of the A76 during the hours of darkness. It was a lot more difficult than I had expected for a number of reasons:

(i) I couldn't see across the corner because my main beam didn't point that way
(ii) I couldn't always see the limit point because my main beam didn't point that way
(iii) I had intermittent oncoming traffic causing reduced vision
(iv) I had (at points) a crazy local behind me wanting to travel significantly faster
(v) It was damp with a temperature of between 3-8ºC

Does anyone have advice on similar situations on how to corner when you can't see the limit point?
I guess that the obvious answer is to slow down but I'd like to hear opinions.

[Ancient]

Driving at night is (of course) very different to driving during the day:
We are not evolved as nocturnal animals, the number and balance of rods (sensitive to dim light, colour insensitive, poor detail, overwhelmed by bright lights, peripheral vision) and cones (colour sensitive, fine detail, poor in dim light, central vision) is poorly designed for night-time activity. What is more, our eyes are poorly designed to work with intermittent bright lights being shone at them (they are slow to recover what 'night vision' they may have developed), especially when this light is at the blue end of the spectrum (Xenon lights e.g.); They are not even good at seeing beyond our headlight pool into the shadows.
This all being so, limit points are different at night: They are necessarily within the headlamp cone and may be defined by that cone rather than the shape of the road; these can (as you have noticed) be less helpful than the visibility available during the day, for determining the shape of a bend (in fact I would argue that limit points are less helpful in real life than they are in a theoretical setting such as a book - few bends around me are single radius and many tighten up again just as the LP begins to move).
Of course at night you also have the advantage that the lights of other cars can at times, show you the shape of the road ahead more easily than trying to read a limit point in the shadows outside of your headlights. This needs to be treated with equal caution though, as there could be an extra bend between you and them, or an unlit hazard such as a pedestrian or tree-trunk!

ETA: v) Danger of black ice: Forget 'making progress' the important thing is to arrive. You will not see black ice no matter what LP you are using, it will appear a normal to good road surface. In this situation IME it is best to slow down for any bend, feel and listen to the tyres and concentrate on skid prevention rather than accelerating out of the bends.

[exportmanuk]

I would say your limit point is the area you can see. You can use other things such are lights in the distance as clues but really the limit of your lights is going to be the point that should take preference. If a local wants to GLF let them pass and get well ahead, don't try to keep up or you may both end up in a ditch.

[jcochrane]

Slink_Pink

Your 4th point reminds me of a night drive I had in Teasdale in a rather nice 911. I noticed a van behind catch me up, he obviously knew the road well as it was very technical and yet despite reduced vision was making better progress than I could. I mentioned to my co driver that I would pull over and let the van through and use him as a path finder. To follow him with his head lights giving great early forward vision was a doddle and it was easy to match his pace.

[Standard Dave]

As one of my instructors said "use his eyes". You have advanced warning of hazards and road condition.

With the usual warning of not relying totally on someone or something else they may make a mistake and if your to close then it will be yours as well.

As others have said the limit point will move closer to you perhaps judged from the centre line rather than the far kerb if you have poor lighting conditions.

[Horse]

I tried some limit pointing . . .

Good article in here:
http://northwiltsroadar.co.uk/wp-conten ... _May12.pdf on page 3.

Includes:
Limit Point Analysis: a number of photographs were shown and the group were encouraged to use their “Battleship” skills to identify the limit point. This was discussed at some length and we were all asked to consider the “Surprise Horizon” limit point instead of the traditional one.

The furthest surprise point (and it doesn't prevent others being closer) is the extent of your lights (when not restricted by glare from mirrors etc.).

[Yes, shamelessly stolen from SH's Mind Driving, and acknowledged in the presentation as such]

[dombooth]

Use the limit point of your headlights and slow down.

Dom

[Slink_Pink]

Slink_Pink

Your 4th point reminds me of a night drive I had in Teasdale in a rather nice 911. I noticed a van behind catch me up, he obviously knew the road well as it was very technical and yet despite reduced vision was making better progress than I could. I mentioned to my co driver that I would pull over and let the van through and use him as a path finder. To follow him with his head lights giving great early forward vision was a doddle and it was easy to match his pace.

It was a double white line system for the majority of the twisty section but I did let him* pass at the first opportunity. Then he sped off into the distance so the advantage was quickly lost. One thing I did note was a classic tailgater feature: right up to my bumper during the curves but I left him for dust when accelerating in the brief straights (still double white lines) only for him to again catch up on the next curves!

*for the purposes of this thread I've assumed "him" but it could as easily have been "her".

[Ancient]

... One thing I did note was a classic tailgater feature: right up to my bumper during the curves but I left him for dust when accelerating in the brief straights (still double white lines) only for him to again catch up on the next curves!

*for the purposes of this thread I've assumed "him" but it could as easily have been "her".

S'funny, I've always found the 'classic tailgater' practice to be to catch me on the straights (exceeding the speed limit to do so) then frighten themselves trying to follow me around the corners, brake in the corner and accelerate onto my tail again. Over a series of corners I usually lose them, only to have them sitting 2ft from my tail as soon as I enter a lower limit area.

[Standard Dave]

... One thing I did note was a classic tailgater feature: right up to my bumper during the curves but I left him for dust when accelerating in the brief straights (still double white lines) only for him to again catch up on the next curves!

*for the purposes of this thread I've assumed "him" but it could as easily have been "her".

S'funny, I've always found the 'classic tailgater' practice to be to catch me on the straights (exceeding the speed limit to do so) then frighten themselves trying to follow me around the corners, brake in the corner and accelerate onto my tail again. Over a series of corners I usually lose them, only to have them sitting 2ft from my tail as soon as I enter a lower limit area.

I'd agree with Ancient, any fool can drive fast in a straight line or exceed a 40 /50 mph limit on a road which a few years ago was a NSL.

I would find drivers speeding up on a straight having driven more slowly that I can around a twisty section extremely annoying. It's slightly less inconvient now I have a subaru impreza with a spare radiator and a hole in the bonnet but still quite annoying to be held up by a less capable driver or vehicle.

[Slink_Pink]

... One thing I did note was a classic tailgater feature: right up to my bumper during the curves but I left him for dust when accelerating in the brief straights (still double white lines) only for him to again catch up on the next curves!

*for the purposes of this thread I've assumed "him" but it could as easily have been "her".

S'funny, I've always found the 'classic tailgater' practice to be to catch me on the straights (exceeding the speed limit to do so) then frighten themselves trying to follow me around the corners, brake in the corner and accelerate onto my tail again. Over a series of corners I usually lose them, only to have them sitting 2ft from my tail as soon as I enter a lower limit area.

I'd agree with Ancient, any fool can drive fast in a straight line or exceed a 40 /50 mph limit on a road which a few years ago was a NSL.

I would find drivers speeding up on a straight having driven more slowly that I can around a twisty section extremely annoying. It's slightly less inconvient now I have a subaru impreza with a spare radiator and a hole in the bonnet but still quite annoying to be held up by a less capable driver or vehicle.

Ouch! I dislike the implication that I'm a fool! I have noticed both forms of intimidation by tailgaters and don't much like either. My intention wasn't to annoy - I think I'd be more annoyed following a sort of one-speed type driver who was slower than I'd like to be both in twisty section (understandable) and straight (very frustrating). In any case, given my experience of that particular road and some comments here, I'd approach the situation differently in the future.

[Horse]

Ouch! I dislike the implication that I'm a fool!

- You recognised something you weren't sure how to deal with.
- You asked for advice.
- You'd already determined the most likely (and, possibly, the most sensible) answer.

None of those are the actions of a fool.

A fool would be the person who decided the 'best' thing to do, but ignored his (and others') advice

[Astraist]

Other than all other pieces of advice mentioned above, it's also possible to look into areas that are illuminated the headlights of other cars to get a better view of the road. Also, when driving on the straight, gentle changes in position and speed can help to illuminate areas to the side of road itself quite nicely. Even a quick flash of the main beam while doing so does the trick.

[aabill]

I would find drivers .... extremely annoying

Perhaps appropriate to remind ourselves that, as recommended by Roadcraft, one should not become personally involved with another driver? One would hope that an Advanced Driver worthy of the name would accommodate and tolerate the behaviour of other drivers, and not become annoyed (aka potentially distracted)...

In answer to the OP, I think that on observing another vehicle approaching, from any direction, one must anticipate that the limit point will come closer and plan to reduce speed accordingly. Same for the limit point closing in because the headlights can not illuminate around the corner to where the limit point would have been in daylight. Where a piece of road has been briefly illuminated by another vehicle's lights be mindful that that piece of road might not remain clear (of badgers. foxes, deer)...

[Standard Dave]

I would find drivers .... extremely annoying

Perhaps appropriate to remind ourselves that, as recommended by Roadcraft, one should not become personally involved with another driver? One would hope that an Advanced Driver worthy of the name would accommodate and tolerate the behaviour of other drivers, and not become annoyed (aka potentially distracted)...

There is a difference between becoming annoyed by the driving behaviour of a driver and becoming annoyed with a driver.

Drivers attempting to prohibit an overtake by speeding up on a straight section after driving slowly through bends would be annoying, would a high speed qualified driver or an advanced driver personalise the situation and be distracted from the job in hand (aka a safe overtake) I doubt it. It's the reaction thats important cutting the driver up on overtake or "brake testing" them would personalise the situation disappearing around the next set of bends never to be seen again wouldn't.

I doubt many people would tolerate careless and inconsiderate driving which attempting to stop overtakes or driving slowly would constitue. I'd add driving so close to the vehicle in front others can't overtake when you have no intention of doing so and poor lane discipline on junctions and multi lane roads.