For a model construction fair, I have build a construction to let a sailplane take off, fly and land again, turn arround, take off, fly etc. The idea was good, unfortunaltly the construction and working could not been tetsted before the fair! So the sailplane flew arround experiencing havy turbulence :) Also taking off did not work as good as planned! I did a lot of testing in the two days of the fair so now I know what parts of the contrsuction need a redesign! Maybe next year I will do this redesigning. The construction was build using a lot of wooden frames to hold the traintrack over a distance of 6 meters. On the rails two special designed carriers where running, while activation of the klimbing and landing was initiated by al lot of gear racks 1 x 4 (3743) between the tracks. No RCX was used. Problems which occurred: - Climbing take op a lot of energy, one standard Lego transformer is not enough to provide the power! - After climbing teh power has to be lower, otherwise the carriers will derail in the corners. - I used to thick fis rope, it had to many capacitance If you want to improve the overall design and want more information, contact me at www.Lowlug.nl UserID: Leqa