The N25 project started life with an eight years old K600 motor we had in storage and wanted to use in a rocket. We also had the reasonable complete 1993 vintage N8 hanging on our ceiling. So those two were matched. On the rocket we replaced the parachute hatch, the parachute hatch release mechanism, the electronics, the lower body tube and the fins. Both the parachute hatch and two of the fins were reclaimed from old N8 parts. The electronics compromised a transmitter and an R-DAS. Like the N8, we also measured rotation.
The launch and flight of the N25 were perfect and it went up in a straight line. It landed almost unscratched. It reached an altitude of 1260m and it rotated around its axis once every 1.8 seconds.
The N25 logo.The N25 is a rebuild of the N8. Some parts, like the parachute hatch (and its release mechanism), the internal part of the electronics compartment and the lower body had to replaced. Here Peter Heeren makes a new parachute hatch from the old lower body.Harry Advokaat and Peter Leemker are discussing the new electronics.The rotation of the rocket was measured using photosensitive diodes.The complete electronics frame, with from left to right, the transmitter, the on/off switch and safety plug connector, the rotation print, and the R-DAS.Harry Advokaat's rotation measure print.Peter Leemker integrates the electronics and parachute compartments.The empty parachute compartment.The fully integrated N25, without motor.Peter Heeren and Vincent Kouer prepare the K600 motor.The igniter is connect the launch system by Peter Heeren.Pleun Punt with the removed safety plug and ribbon.Lift off.The N25 just above the tower.The N25 on a flew a very straight course.Landing.The only damage was a lose fin, which can easily be glued.Results from N25's R-DAS computer. The X-axis is time in seconds, the blue Y-axis is altitude in metres and the black Y-axis is gravity. The first red line is lift off and the second is the top.More N25 R-DAS readout. The X-axis is time in seconds, the blue Y-axis is altitude in metres and the green and purple Y-axis are the rotation. The first red line is lift off and the second is the top.