Nissan Patrol 4x4 (Africa)

I'll be posting my trip report from Sani here at some point when I've caught up with work and sorted out the photographs.

However, a bunch of people have asked me why the trip was so stressful. The video link posted below should explain it all.

A few things about Sani before explaining what happened.

There are three bends on Sani which get very little sun in Winter. When it has snowed, black ice forms in these bends. Descending is *scary*. Driving down, the vehicle does slide all over the place, and all you can do is keep it on the road.

In addition to this, ascending vehicles have right of way on the pass. If you're coming down the pass, you are supposed to wait for them.

The issue here is that if you're coming down, and you've entered a dark section (the iced ones), you're basically committed to continuing with it until you've gone around the switchback and back into the sun. You cannot safely apply brakes. And you cannot really stop. As such, most of the time on the pass, vehicles ascending will wait for the dark section to be clear before starting up there.

This is what happened on our way down. We waited until we saw no additional vehicles coming up, and we entered the last icy section (you'll see - it is a long one). We idled down in 4L without using the brakes, but the vehicle still slid all over the place. At some point, the rear end was sliding out a bit to the right (I imagine I was almost 10 degrees to the track), but I was controlling it. And then some maniac tour operator came screaming up the pass, entering the switch back corner just before we reached it. The video is not complete (Reinette - a friend of my father's who was travelling with him stopped recording as she wanted to be ready to provide assistance should the worst have happened), and you won't quite see how close it was, but I imagine we missed each other by millimetres in the end. Scary drive...



I'll be posting the rest of the trip report later (probably tomorrow, I think), which will also include a ton of stuff in terms of what I learned. But just thought I'd post this first. Hope it makes sense.

PS: Sorry - video is relatively poor quality, and my GoPro battery was flat on the way down. :(

Hi Ian

Thanks for the info .

I am going up Sani on Saturday and thereafter ~ 700 km through Lesotho

Those are the bends we discussed over the phone before you left..... they are scary to say the least !!!

You approached the icy area perfectly, slow as possible. You are lucky you drive a manual..... imaging trying that in an auto and having to brake to control the speed. There isn't much one can do for a situation like that, other than exactly what you did. Well done on a new learning experience !!!

As we discussed the other night, regarding snow chains, yes in this particular 50m section chains may have helped, but again it is very "subject to the terrain at that moment", but may also have given you less traction. so its a very difficult decision to make whether to stop for 30 minutes to battle to fit the chains, or to approach the obstacle as cautiously as you did. Black ice is a bliksem, and you handled it perfectly.

Unfortunately having to give way to ascending vehicles is also somewhat tricky as you have to concentrate on getting yourself down and sometimes when one is committed in the obstacle you have to hold firm and keep calm... back to that thing I always say.... " stop, breath, think, breath, act, breath".

Well done bud !!

mattk wrote:Hi Ian

Was also there recently, had M/T tyres and no problems with grip at very slow speeds; basically broke through sections of ice. But fortunately had no idiot drivers to contend with on Sani. Over the Menoaneng pass to Taba Tseka there was one taxi driver on smooth tyres: he had real fun and communicated with me in sign language that let me know his feelings exactly. Not my fault he had aeroplane tyres (air on the inside, plane on the outside). Those tyres were so smooth I am certain he had to cover them at night to stop the mosquitos puncturing them....

What size tyres where you running?

i am wondering if skinny tyres would not fare better on ice than wide tyres. Theoretically skinny tyres would cut through the ice easier and cause less chance of aquaplaning?

See the pic Ian posted on the patrol spotting thread. The tour guide got real cheese cutters on his patrol...
http://www.patrol4x4.co.za/viewtopic.ph ... 140#p76419

Unfortunately, it doesnt matter what tyres you have on....unless you drive on steel studded tyres, you will slide. The ice is very hard and doesn't always break, like I said before, even with chains on you may still not get the chain to break through the ice to give the chain sufficient grip within the " dent you may have made in the ice. Snow on the other hand is a totaly different driving experience. Here muddies and or the addition of chains will make snow (or soft ice) a lot easier to drive on

Sani is a bugger, because if you go up there in summer, you will wonder what all the fuss is about.

But with ice on it's a far different kettle of fish I'm sure.

Having myself never driven on ice, I wonder: what will the effect of tar be on ice formation?

Peter, that black ice on tar is VERY scary.... you don't always see it till you are on it. As a comparison, it feels like when you are on an ice rink with normal takkies. You can walk around slowly, but try move quickly and you will see your ass very quickly. There is nothing for the rubber to "grab" onto, so in theory, you are aqua planing even while stationary. Once the vehicle is sliding there is almost no way to stop it other that turn into the slide and play with the accelerator a bit.

SJC wrote: What size tyres where you running?

i am wondering if skinny tyres would not fare better on ice than wide tyres. Theoretically skinny tyres would cut through the ice easier and cause less chance of aquaplaning?

See the pic Ian posted on the patrol spotting thread. The tour guide got real cheese cutters on his patrol...
http://www.patrol4x4.co.za/viewtopic.ph ... 140#p76419

Fanus,

I was running 285/75/16 muds. I deflated to 1.3 as I did not want to go to flat (ie: have enough pressure to "break the ice"). However, this only worked on thinner ice. The deep ice in the bends did not work at all.

The M/T's did give me a significant advantage driving up Sani. At one point, when my father got stuck on the ascent, I stopped just before the sun started again (stupid), and went back to help. When we'd managed to get him unstuck, I almost got stuck myself. But then decided I'd just floor the vehicle. It came out. I do not think this would have been possible with a A/T tyre (especially not my old Dunlop A/T's).

Peter Connan wrote:Sani is a bugger, because if you go up there in summer, you will wonder what all the fuss is about.

But with ice on it's a far different kettle of fish I'm sure.

Having myself never driven on ice, I wonder: what will the effect of tar be on ice formation?

I'll be honest and say that they should not tar Sani. I think it's safer leaving it as a gravel road. If the road freezes, I think one would still have better traction and similar than on tar, because there is the possibility of the ice breaking. (ie: the gravel road "gives" a little). Also, because it's gravel, I think the water will drain a little better before it freezes than a tar road.

However, that is just my opinion, and it is unqualified.

ricster wrote: ...snip...
Well done bud !!
.../snip...

Thanks Cedric. That was probably the most stressful drive I've done. But we're still here. I must get around to writing up the trip report, but I'm battling trying to get all my work done before tomorrow and also getting ready for the river trip... :)