Hi Steelo,glad you open'd this thred. Millsy, what about going down hills? I think a vertically mounted is better than no flag at all.
Yes, I think I see what you are getting at. It would be not a problem on the way down, but if there is a sudden leveling off at the bottom then the top of the flag would be closer to the level ground than normal, when the car's front wheels have not yet reached the level ground. But I don't think that would occur very often in nature.
The only time you would get such a quick change in angle would be at the bottom of a hard rocky track going into a sandy creek maybe, and chances are you would not be flying a flag anyway in those situations. But if you are you would need to be careful you don't poke your flag into the car in front. But if you did you were probably driving a lot closer than normal safe separation anyway.
Sand hills have a more gentle curve at the bottom of a hill due to erosion of the sand down hill. Any sudden V shape would be filled in by sand due to gravitational, wind and rain effects.
I would be interested in knowing if anyone on the forum has actually crested a hill at the same time as another vehicle coming in the opposite direction. If by some fluke this has happened to them, and the other vehicle was actually flying a flag, did they see it in time to hit the brakes? This is a bit different to seeing a flag come over a crest when you are still 10 metres or more from the other vehicle. Since you are not near the top you do not have your bonnet obstructing your view. The flag(s) are really only of any use when both cars arrive at the top at the same time, otherwise its just another accessory the shops are flogging to improve their profits.
So, has it really been a crash preventer for anyone on this forum?
Don't get me wrong now. I have never had a grudge against sand flags, or 4x4 shops, but this thread has just got me thinking about the geometry of it all.