This blog covers the day to day progress of water rocket development by the Air Command Water Rockets team. It is also a facility for people to provide feedback and ask questions.

Wednesday, January 27, 2010

1st splice phase complete

Last night we finished gluing the 12 x 2L and 10 x 1.25L spliced pairs with the Sikaflex glue. The splices went together quite quickly, but preparation took a bit of time because it included heat shrinking the bottles, curling the edges, cleaning with alcohol, sanding and applying the masking tape before gluing could begin.

 Next we need to glue on the outer sleeves with PL and then re-enforce them with the other bottles and glass strapping tape. This should happen over the next few days.


Saturday, January 23, 2010

Splicing, splicing and more splicing

With the recent flights out of the way, we are now solely concentrating on getting Acceleron V back in the air. The first thing we need to do is make up more of the new spliced pairs we have been testing. Over the last 3 months we have been slowly collecting bottles from friends and family, so now we have some 70 odd bottles ready to splice.

We will be making up a stock pile of spliced pairs, not just for Acceleron V but for other rockets. We are also going to have a go with the 1.25 bottles at making spliced-quads. 4 bottles spliced together with a neck at either end. This will give us ~4L in a 90mm diameter body. We'll still be able to join them using Tornado couplings, but they should give us a little more performance. If they go well in tests we may use them on Acceleron V's sustainer.


Thursday, January 21, 2010

In-line deployment mechanism

We've updated our main website with the rest of the flight day report from 10th January 2010.

The update shows more details of the lightweight deployment mechanism we have been recently testing. The Tomy timer version weighs 35grams.

The update also includes a highlights video from the day.


Thursday, January 14, 2010

Mercury Switch Experiment Results

We've completed the write-up for the experiment. The full results are available here:

I was surprised by some of the results while others were as expected. Included are pictures, altimeter graphs and a video of the entire experiment.

I was going to include the full flight day report from Sunday in this update, but because it was kind of long anyway, I decided to separate it. The rest of the flight report will be done over the next few days including a description of the lightweight deployment mechanism and a video of how it works.


Thursday, January 07, 2010

Flight MicroLab - Mercury Switch Experiment

One of the things we want to fly this weekend at Doonside is a small science experiment. The main intention is to demonstrate how mercury switches behave during flight. It is a very common question we get asked all the time. "Why not use a mercury switch to detect when the rocket tips over at apogee?" ... it's a reasonable question since the system works well on the ground.

I thought video taping what they actually do in flight should give people a better understanding why they don't work the way they think they should.

Experiment setup:

There is a small digital video camera looking through a lens at a set of three mercury switches. Two are mounted the way people would typically mount them and the other is mounted upside down. They are wired to an LED each so you can see when in flight they actually activate. There is also a light source (white LED) above them so the mercury can be clearly seen. There is also a barometric recording altimeter mounted on the side to correlate the activation timing of the switches vs altitude/speed.

The parachute will be set to deploy later than normal so we can see what happens through apogee and somewhat beyond. After we have flown it I'll post the results to our regular website again.

Here is the MicroLab before being installed in the rocket. The rocket will be a Polaron style rocket of around 9.5L. capacity. The rocket is made up of the old Acceleron V bottles so we will be launching it at only about 110psi.

Front view

Back view with power turned on

View from inside the experiment


Saturday, January 02, 2010

Preparation for launch day

Happy new year! Having had a nice break over the Christmas and new year we are back in full swing with rocket development.

The next launch opportunity is on Jan 10, so we are working to have a number of rockets ready for the day. One of the rockets we'll be testing is the new smaller and lighter deployment mechanism. It weighs less than half of the one we have been using.We'll test it on a small rocket first and then if things go well, we'll extend the rocket and try it at higher speeds and altitude.

We are also preparing a Polaron style rocket that will do a number of in-flight experiments.

Dad has finished upgrading one of our air control panels which will now be able to deliver two different pressures each up to 300psi. This will be useful for the upcoming re-enforced rockets to be launched at higher pressures.

Some goals for 2010 include:
- Getting Acceleron V back in the air on a number of flights, and pushing it to its limits.
- Finishing off V1.7 of the flight computer.
- Getting the website extension completed.
- Higher pressure launches.
- More instructional videos and construction instructions.

We hope everyone has many successful flights with their rockets this year.