What I wanted to test

I am using a Pico AA2 Altimeter and I wanted to run a few tests:-

1. Test that the Altimeter seems to work – i.e. will detect launch and can detect Burnout and then Apogee. I do this test because I wouldn’t want to fly with a faulty Altimeter
2. Test that the Altimeter with the 2 x 3.7v 180maH LiPO batteries can supply the current required to fire two e-Matches one after the other
3. Test the Cable Cutter and the procedure to set it up.

The Set-up

Here are photos taken during the set-up.

 

The Results

Here are the results

Detection of Launch Events

We had the Pico AA2 pointed up while it was configured with 2G = 8 which is equal to about 1/4g. Because the G’s are more than 0.25g, the Pico AA2 thinks it has detected launch.

I then turn the Pico so that it is horizontal. As I do this, the G’s pass through zero, which it takes a motor BurnOut. Then it looks at the area under the curve as the rocket “deaccelerates” and when this area is equal to area under curve between Ignition and BurnOut, it then assumes we have lost the velocity we gained; i.e. we are at Apogee. So it fires the Apogee (A) event. Then, because we are below the 800ft, it fires the Main 0.5 seconds later.

 

Apogee

This will ignite black powder that will separate the top section of the rocket (including the nose cone) from the main air-frame. In this test, we just want to make sure the igniter does it’s job. Ignites.

 

The Main

Here we test that Main Output fires.

Conclusion

So I ran this test and I’m now fairly comfortable that the Pico AA2 works. I also observed both igniters working, which means the Pico AA2 batteries can be depended upon.

However, the Cable Cutter did not fire. I suspect this is because of two things.

1. The piston is a dud – it doesn’t have a “cutting edge” like other photos show
2. A significant portion of the black powder gas went out the back.

Here is a photo of the piston.