I read with interest the article on the timber roller coaster in Norway (TTJ October 28, 2000).
Unfortunately there some factual errors in the article which I feel need to be corrected.
The timber used was southern yellow pine (more correctly southern pine) from the south-eastern US, ranging from Virginia to Texas. Columbian southern yellow pine does not exist.
The reason why the two north American species were chosen for this roller coaster is very simple. Both Douglas fir and southern pine are the strongest softwood species that exist commercially and this is particularly true of southern pine, whose load-bearing values are the highest of all softwoods. A further point that needs to be remembered is that when building a structure like a roller coaster, large dimensioned timbers are needed and these are readily available from US sawmills, which is not necessa-rily the case in Europe.
A second advantage of southern pine is that it readily accepts preservative chemicals without the need to incise to aid penetration. This property ensures total penetration, thereby ensuring a long life span for the roller coaster.
The article mentioned that the Canadians were the only people currently doing this type of work. This again is incorrect. I am aware of timber roller coasters that have been built by US companies in a range of countries including the Netherlands, Germany, Spain and Japan.
