Wednesday, January 7, 2015

Staging Mechanism for Air-Start of Multi-Stage Water Rockets

Over the past few weeks, we've been engaged in a discussion on the Water Rocket Forum after we posted a video we found on YouTube about a toy Water Rocket which we had never seen before. The toy had a unique launching system where the rocket is tossed in the air and a lanyard attached to your wrist activates a launching mechanism when the rocket reaches the end of the lanyard.
A forum member going by the name "Bugwubber" took up our challenge to reverse engineer the toy, and was able to figure out the system by analyzing the video frame by frame. He came up with some diagrams and a video showing how it operates.
We built on Bugwubber's work, by combining it with our own Radial Deploy System to create a concept for our own type of staging system, for which we have started a new project series to share our work. 
A unique feature of the system is that it has the ability to be initiated while in flight at any point in time, simply by changing the time delay after launch. Instead of the typical staging system that will only fire at burnout, this new system is cable of delaying until a more favorable booster firing altitude has been reached. This ability is known as "air-start" in rocketry terminology, so we adopted it for this design as well.
We've linked to the first video to kick off the new project, showing our concept and an animation illustrating how it operates. We hope you will follow along as we continue to build and test this idea in the coming months! 



  1. How are you proposing to pressurise the upper stage?

    1. A one way valve design allows air in but will allow it to come back out at a much slower rate. This will allow the air in from the bottom stage but will let it come back out at a much slower rate. That way we can drain the air if we abort the launch.