How should I categorize this game? It was a very close call between action and sports and the only reason I put it here is, that it's supposed to be racing. But a very action-based racer.
First of all, I should point out that this is not a commercial game. It was made by Bullfrog when they were working on High Octane, so Tube is most likely some kind of study object. It has been published in Germany by the well-known magazine PC Player (there are even their logos appearing in the game!). So the gameplay is a very early version of High Octane.