Bjorn/Bjorn Again

The general outlines of the rocket at early design stage.

By Pleun Punt

The rocket Bjorn was built during the summer of 2003. It has a length of 2,4 metres. The tube is a cardboard with a diameter of 100mm covered with glass fibre. During its first flight at NLD18 on 5 September 2003 its R-DAS unit just recorded the flight. The parachute was to deploy using the ejection charge of the AeroTech I284-W. Although it was a nice launch the parachute didn't deployed well and damaged the rocket in several places. During a hectic period of 10 days the damage was repaired and during ALRS IV on 20 September was launched again, renamed as Bjorn Again. A J350-W brought the rocket over 800m high. The R-DAS was now connected with an igniter to an ejection charge to deploy the parachute and backed up by an ejection charge on the motor. This time the rocket parachuted perfectly and was recovered intact.

The nose cone with shoulder, which was made from tube coupler. The electronics frame. The rings are again from made from tube coupler. The 54mm motor mount and 38mm adaptor. The boot tail. The lower part of the rocket before final assembly. At last, finished!.

Bjorn in the tower at NLD18 on 5 September, 2003. Launch with an AeroTech I284-W. It had a good flight, apart from not deploying the parachute... The R-DAS graph of the Bjorn.

So only 10 days until the next launch and a lot of repairs to made, like the boot tail. The top of the lower body part of the rocket. And a fin. The same fin, almost repaired. After it was sprayed I couldn't see which fin was broken anymore. This 200mm length of tube replaced 100mm of damaged tube. I reinforced the tube with glass fibre and later primed it.

At ALRS IV on 20 September just before launch one fin was damaged. This was easily fixed with 5 minutes epoxy. Assisted by Thiemo van Engelen and an Argos member, Bjorn Again is prepared to be launch. (Picture: Thiemo van Engelen) Lift off. (Picture: Thiemo van Engelen) The J350-W propelled the rocket to great heights. (Picture: Thiemo van Engelen) This time it landed safely, much to my relieve. The R-DAS graph of the Bjorn Again.