After designing and constructing our cutdown device prototype we like to call the ‘Funbox’, it has come time for us to test! Since we still haven’t set up our tethered balloon system, we’ve decided to test from the spot we’ve done all of our previous tests from – the balcony.
In our test video, we started with a fishing line spool system set up on the ground floor. Ben (who simulates the balloon) stands on the second floor at the balcony and then lowers the Funbox (which is connected to the ‘balloon line’) down to the ground floor to be hooked up to the payload. On the ground floor, the fishing line is taken from the spool, through the Funbox, through the payload parachute loop, back out the Funbox, and is tied off at the spool once more.
After the payload and cutdown device is rigged up, Ben starts pulling up on the string simulating the balloons ascent. We’ve learned that if we just let the cutdown line spool run, the payload will droop from the Funbox and basically fall to the ground. However, if we keep the line too tight, the balloon will stop ascending (in this case, Ben would just get kind of annoyed). So, the name of the game for us is to watch the payload and add some resistance to the spool as it gives some line away. This way, it doesn’t stop our ascent, nor does the payload droop.
The last step for us begins at our balloons maximum height – or in this case, when Ben can’t hold the line any higher. It is at this point where the cutdown line must be released of all tension in order to release the payload. This is done by cutting the line where it is tied off, back down at the spool. Immediately, the payload drops and deploys its chute descending gently back to the Earth.
Check out the video!