How to Launch




We launch with the Southern California Rocket Association at the Santa Fe Dam in Irwindale, CA.


Here are some hints for having a successful TARC launch:

What to Bring
You'll want to make sure you have the basics in order to ensure a fun and productive experience. Here are the necessities:

1. Tool Box - for launch preparation and any adjustments (see the "How to Build Page" for its contents)

2. Folding table - to serve as work table for rocket preparation

3. Chairs - think soccer game type folding chairs, to rest your legs between rounds of launches

4. Canopy - to protect you once the sun comes out!

5. Rocket, Motors, and Eggs!

Eggs



We've had success with "Eggland's Best 12 Grade AA Large" eggs. We recommend that you bring a scale to the market in order to weigh the batch before buying them to make sure that they are 57-63 grams. You would be surprised at how far off the weight of the eggs can be from what is listed on the carton. Bubble wrap around the eggs has worked really well for us-- we rarely break an egg!





Wadding

In some rockets, we add about 2 inches of cellulose wadding (aka dog barf). We know it's 2 inches because we tamp it down with a ruler! In other rockets, we use a 6" or 9" square of Nomex. Sometimes we do both for good measure.

How to Fold the Shock Cord

You want to make sure the shock cord easily comes out of the body tube and does not get tangled. Take your hand and wrap a portion of the shock cord (as divided by the attachment for the parachute) around your pinky then back over the top of your hand and around your index finger. Continue until you run out of cord then fold it in half and secure it loosely with a rubber band.
How to Fold the Parachute

Fold the chute in half, and then in half again. Fold horizontally in thirds by making a "Z." You should have a triangular piece in the middle, on top of the folds. Then tightly (think as tight as stuffing a sleeping bag back in its case!) roll the chute up so its just a bit bigger than your finger. Wrap the strings around the chute so it's ready to connect to your folded shock cord.

How to Prep the Altimeter
We use a TARC-approved PerfectFlite Pnut altimeter. Hold the card carefully with two fingers (one on each edge as not to touch the circuit board) and plug in the tiny jumper shunt across the power pins to activate it. (We tie thread to it so it doesn't get lost.) You should hear a beeping. Once you hear the constant beeping, place it in the altimeter tube, circuit side facing towards the inside of the rocket. The pressure sensor (marked "U3") must face the window cut in the altimeter tube. Cap the tube with a small piece of foam to stop the altimeter from coming out. Seal up the altimeter bay.

Below is a screen shot of the data recorded by the Pnut altimeter.

How to Prep the Motor


Do not install the motor when you check-in your rocket for the first time. After that, the Safety Officer may say that it's OK to check-in your rocket for repeat flights with the motor in. But do not put the ignitor in until you are at the launch pad.

Pull back gently on the engine hook (it will snap off with force!) to install the motor. Wrap several layers of masking tape around the motor and hook. You don't want your rocket to spit out the motor!

You may encounter two types of ignitors. Ones that have two wires with insulation that must be stripped off and ones that have a single wide copper strip. Ask for help putting the alligator clips on the ignitor the first time you launch.
How to Fill-out the Flight Card
You will need to fill out a flight card for each round you fly your rocket. The team captain should write and sign their name in the blanks (most likely using their NAR insurance) and signify the motor type (e.g. Aerotech E30-7T) and whether or not you'll be using the standard, supplied launch pads or your own. The name of your rocket should be "TARC Test." The name of your rocket and the type of motor most likely will be announced over a loud speaker.

As many team members as possible, including the team advisor, should join the National Association of Rocketry. Your support of NAR keeps the sport safe, provides scholarships, provides insurance, and you get an awesome magazine sent to your home. The cost is about $25 per year.

Recording Data

Collecting data is a must! You should fill out a Launch Log like this one for every flight to insure that you can duplicate the same flight or determine what causes discrepancies!

Bring a digital scale (0-1000g) to the launch. You will find it necessary to add or subtract grams of weight to hit the target altitude.

Checking-in Your Rocket
Where we fly, a courtesy is given to TARC members, and we are allowed to cut to the front of the line at the check-in table. Have your flight card ready along with your rocket. Carry the motor and ignitor separate from the rocket. (Hint: Tape the ignitor to the body tube so it doesn't get damaged or lost.) Be ready either to go back to your table to make adjustments or, more likely, go straight to the launch pad and get ready to fly!


The Launch Pad





It is advantageous (but not necessary) to bring your own launch pad, rod, controller, and battery. You will be able to better control the angle of the launch rod, and therefore your rocket's trajectory, if you use your own materials. We use a protractor to record the angle. Also, you might be able to squeeze in more rounds since you'll be using your own, separate supplies. A fair warning, it takes time to set up and manage your own launch pad, but we've found our rocket's flight results to be much more consistent as a result. Go to a launch first before deciding to invest in these supplies.




What to Expect

Rocketeers are more than willing to share their knowledge if you just ask! Introduce yourselves to those working around you - you never know when you may need to borrow something. Look for ways to help others in return. Take the time to tell young kids what you are doing, and explain to others what TARC is all about.

The adults running the launch do not get paid for this service, so be sure to thank them and even offer to stay to help clean up the launch site. Also, don't take it personally if you are talked to sternly if you breech safety protocol - it's for everyone's own good.

What to Wear!
Come prepared for the ever-changing temperature. Wear layers (think sweatshirt and t-shirt with jeans). Wear comfortable shoes for running and be willing to get them a little bit dirty. Wear sunscreen and bring a hat. Bow optional!