The dress rehearsal of the Stratos II launch took place on the 28th and 29th of August 2014 inside the Dreamhal Building of the TU Delft. During the rehearsal the electronics team, capsule team and the propulsion team assembled their systems. Moreover, the launch tower set-up and the mounting of the rocket were rehearsed and some last-minute drilling on the structure of the rocket was performed.
Capsule Team assembling the nosecone and the parachute system
The launch was simulated with an actual weather station to measure the wind direction and wind speed and a large screen showing the vital functions of the rocket, such as the valves and actuators of the hybrid rocket motor. If anything goes wrong, the screen will show the mission control team what is wrong and counter measures can be taken.
Mission Control Center during the dress rehearsal
The capsule team assembled the parachute system with the entire cabling system and spanning mechanism. This turned out to be a more time-consuming task then planned. The importance of the dress rehearsal was proven, because at the launch site it has to be clear how much time each task takes in order to prevent running out of time and to start ahead of time if needed.
Parachute system being inspected
Assembly of the clampband system
The hybdrid propulsion team assembled their oxidizer injector and valving system that will be placed in the rocket motor. The propellant grain which consists of a mixture of sorbitol, parafine and aluminium powder was placed inside the rocket, however the tank was not filled with the 80 kg of nitrous oxide it needs for launch, because this would add enormous safety risks inside the Dreamhal building. On the launch site in Spain this risk is eliminated due to the much larger distance between the Stratos II crew and the rocket itself. In Spain the rocket will be filled by systems that are controlled from a safe distance from the rocket.
Hybid Team assembling the valve system
Rocket motor of the Stratos II
While all the teams were completing assembling their part of the rocket, the launch tower was set-up and the rocket was mounted on it. This was done in two steps,where first the launch tower without rocket was erected and afterwards the launch tower with rocket was erected. While doing this all safety measures were taken into account, such as wearing safety boots, wearing safety helmets for the crew-members standing under the rocket and having one person in charge during the entire operation to prevent chaos. During the launch tower set-up one hick-up was encountered: one of the bolts on the rocket prevented the rocket from being mounted on the launch tower, which meant that the bolt had to be unscrewed while mounting the rocket. This again proves the necessity of the dress rehearsal.
Launch tower with rocket mounted being erected
At the end of the day on the 29th of August news reporters from TU Delta and Algemeen Dagblad took some pictures to add to their news articles. An update of these articles will be posted when it is released.