After you have built you model, you will need to store it somewhere. The model should be kept in a box to avoid getting damaged. The easiest way to get a box is to go to an office supply store and buy either a cardboard shipping box or a cardboard Bankers Box. In either case make sure the box is big enough to hold you model. The model is about 22" long and the stab is just under 14" span, so the box must be at least 23" long and 15" wide. It also needs to be at least 8" high. Here is a photo showing how the model would sit in the box.

    The last thing I want to discuss in a little bit of detail is winding technique and flying technique. I have already described the 50/50 winding method, which is winding half the turns with the rubber stretched out and the other half while walking towards the model, and the next thing I want to introduce is a torque meter. A torque meter measures the twisting force of the motor as it is being wound. The torque can be an indicator of how high a model climbs, how it acts right after launch, as well as give you and indication if the motor is going to break during winding. Here is a photo of my torque meter and winding stand. This equipment allows me to wind a motor and transfer it to my model by myself without the assistance of others. You can build a simple winding stooge to hold our wound rubber motor.

    Torque meters can be made or bought from indoor suppliers. All a torque meter is made from is a piece of thin music wire, about .020" diameter and 5" long, which has one end fixed and the other end hooks onto the rubber motor. As the motor gets wound, the twisting force increases, and the torque meter wire starts to twist as well. How it twists is an indication of how much torque the motor is producing. The higher the torque, generally, the higher or longer the model will climb. At this point it is highly recommended that you start to record your model flying sessions in a notebook or similar type of log. What you want to record is data such as turns, rubber size, rubber length, torque, flight time, turns left in rubber after the model lands, how high it climbed, and any other comments about the flight which may be useful too you in the future. This may seem like a lot to keep track of, but believe me when you have not flown your model in a few weeks, you will be surprised at how much you forget.

A typical flight record could be like the following:
Rubber length: 15.5"
Rubber width: .095"
Rubber weight: 1.98gr
Turns: 1650
Back off turns: 30
Torque: 13.6
Flight time: 3:09
Turns left: 100
Comments:  Climbed to roof, hit the ceiling two times, then peaked out just beneath the lights. Trim was fine, stalled slightly when coming down, may have hit some bumpy air.

    One of the terms you may not understand is back off turns. This refers to turns which you unwind before hooking the motor on the airplane. In the example above, 1650 turns were put into the motor, then 30 turns were unwound, and the measured torque was 13.6. The reason you back turns off is because the torque levels may be too high for the model, either structurally, or simply because the ceiling is too low. In this example, the torque may have been 18.0 after the 1650 turns were put in, but after unwinding 30 turns the torque lowered down to 13.6. The lower torque level means that the model will not climb so fast after launch. If you are flying in a higher ceiling, then you may not want to back off any turns at all, and use the extra torque to gain more altitude.
    Please note that some models may act strange under very high torque levels. Some will fly straight, dive, or other things under these high torque conditions. If you run into this, then note what torque level your model does not like, and then back turns off of the motor to lower the torque level. Your model may not have any problems with very high torques, in fact it may climb very fast under these conditions. I have hit the ceiling in our 26ft gym in about 10 seconds with such high torques. Unless you have a higher ceiling, I would suggest backing off a few turns if this is your situation. When your model climbs and flies that fast under the high torques, it hits the ceiling or rafter that much harder and can damage the model. So in general, I would back off a few turns to take the extreme torque out of the model when you are winding close to max rubber turns.
    The other item to consider during test flying is how many turns to put into the motor. The motor has a finite number of turns it will take before it breaks. The turns chart is a good starting point for figuring this out. The only real method is to make a few identical motors, and then wind them until they break. Each motor should be 'broken in' before flying it on the model. Breaking in a motor is a process of prewinding the motor to allow the rubber to take an initial stretch from the stress of a first wind. A 14" long motor that has never been wound before will be a little short of 15" long after it has been broken in. To break in the motor, look at the max turns chart and then wind to 90% of that value. So if a motor would take 2000 turns, then do a prewind to 1800 turns and then let the motor unwind. After it unwinds, check the length of the motor and verify that it has stretched out.
    For test flying the model right out of the box, I would try about 50% of max turns just to verify the model trim settings. For flights after that I would go to 80%, 90%, then 95% of maximum turns. If you wind the motor multiple times at 95% of maximum turns then the motor can become 'tired'. What this means is that the rubber looses some of its stored energy potential, and the model performance will start to suffer. If this happens then fly on a new motor and let the tired motor recover for a little while.

FLYING:
    The last topic is flying technique. When you are flying you should take note of how many turns are left when the flight is over. If you have too many turns left, then your motor is not powerful enough and is too small in width and or too long. If your model runs out of turns before it lands then your motor is too short and or too wide.  Ideally you should land with only a few turns left in the motor. I would say if you land with 100 turns or less then the motor is just about right. Any more than that and I would adjust your motor size and length. Because the rules limit us to a maximum of 2 grams of rubber, changing the width of the motor automatically changes the length of the motor.
    As you fly in different height buildings you may find that different motors seem to fit your model best. In general, the lower the ceiling, the shorter and wider the motor will end up being. In higher ceilings, a longer thinner motor with more turns and maximum torque (very little back) will work better.
    Depending on your flying site you may or may not have a smooth ceiling. Most gyms have girders or lights hanging down in them so it is inevitable that your model will hit something. Do not be overly concerned about your model colliding with obstructions. It is part of the model flying and actually can actually assist your model. For example, our gym has a divider going down the middle of it that hangs down about 2 feet below the girder. If my model is climbing too fast and it hits the divider, then it will drop down below the divider and start climbing again. It will do this repeatedly until it no longer has the power to climb up again. The benefit is that it prevents my model from flying into and above the girders which will undoubtedly catch and snag the model and causing the flight to be terminated. So it is possible to use the building structure and layout for strategic reasons.

Having said that, I am afraid that this is the end of the CD. I hope that you have learned a lot about how to build a model as well as how to fly a model. I wish you luck in your Science Olympiad competition and if you have any questions I can be found on my indoor mailing list. So remember to keep good flying records and most of all, enjoy your new model airplane!

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