Blog #7: Final Blog

H20 12oCk3T Reflection.

These past few weeks in physics we made and launched water rockets. Through many trials and tribulations, we discovered what worked and what didn’t work. We also found uncontrollable variables that affected our launch. By using what worked and the uncontrollable variables to our advantage we were able to have a successful final launch.

During this project we created 2 rockets. The first rocket (on the left) we made helped us to understand what modifications worked and didn’t work. This rocket was used for the first 3 launch days. On launch day 1 we did not add any modifications. We only added 500 mL of water and 40 psi of pressure to the bottle. The hang time of the bottle was 4 seconds. For day 2 we added fins to the rocket. Once again we added 500 mL of water and 40 psi of pressure to the bottle. The hang time of the bottle was once again 4 seconds. We concluded that fins slightly helped the rocket stay in a ballistic pattern while airborne in addition to creating some drag. The difference in the two launch days was that there was little to no wind on the second day. This could have possible been a factor to why the two hang times are the same. The wind on day 1 was very strong and might have helped to keep the rocket in the air. On launch day 3 we added a parachute, a nose cone, and extended the length of the bottle. We added 500 mL of water and 20 pumps of psi (because we lacked a pressure gauge we couldn’t get a more accurate pressure). The rocket had a hang time of 5 seconds. Since the hang time was 1 second more than the two previous days we concluded that the parachute, nose cone, and length extension were important to the rocket. What we had yet to figure out, however, was which addition made the most difference.
On launch day 4 we had to create a whole new rocket (in ten minutes) because we forgot ours. With this new rocket we did almost the same style as the first. The difference was that the extension to the bottle was open, so the parachute can go inside, and a bigger parachute. When we prepared to launch we added 800mL of water and an unknown amount of psi (no pressure gauge). The hang time from this launch was 6 seconds. At this point we thought that the parachute was key to a successful launch. We figured this out because there was a strong wind that day and it carried the rocket quite some distance from our launch spot. With this information we started to prepare for the final launch day.
In preparation of the final launch day, we went into the SPC (student production center) to create the most efficient parachute we could. To complete this task, we used this website: http://www.lnhs.org/hayhurst/rockets/. It explained, in detail, what the most efficient parachute looks like. On final launch day, we were going to launch in the dark, being that we had never launched the rocket with our newly constructed parachute. Our first two launches were below the ten second time requirement because our parachute was not deploying correctly. The third time, with a little help from Mr. Blake, we folded the parachute in the same manner one would fold a parachute for the toy soldiers we played with as kids. This time, the third time, it deployed like a charm. However, it was still about to hit the ground in under ten seconds. With a little less than 10 feet to go before it hit the ground, a sudden gust of wind came, and our parachute had its moment in the limelight. The bottle was carried by the parachute and the wind for over seventeen seconds until it hit the ground.
In closing, the reason we were so successful was due to careful planning (with regards to the parachute) and luck (from the wind).

Blog #6

WE DID IT! WE DID IT! WE DID IT YEAH! 17.5 Seconds!!!!!!!! For the winnnnnnn!

For our final launch we created a whole new parachute. It was designed in the shape of a circle, with sixteen holes and sixteen different strings attached to it. We found the design of the parachute on this website: http://www.lnhs.org/hayhurst/rockets/. On this website it showed us all the steps from folding to cutting and taping and hole punching. We used fishing line and duck tape to attach it to the outside of our rocket. This parachute was the key to our success.
    We filled the rocket with 800mL of water and applied approximately 80-90 psi of pressure. With this amount of water and pressure we figured that it would go higher. We did this for 3 launches, the difference in all of them was how our parachute deployed and how it was placed on the rocket. The first launch our parachute deployed very late( very close to the ground) and it did not increase time in the ayer at all. The second launch, we stuffed the parachute in the rocket thinking it would work better. Instead it did not deploy at all. After discussing what our problem was with Mr. Blake, we decided that we should fold the parachute like how the little toy army toy parachuters parachutes are folded. Then we started our third launch. The parachute fully deployed late in its flight. Luckily it was a very windy time of day and our parachute was so well made that the wind lifted the rocket up and extended the time in the ayer. Our parachute plus the weather conditions of the day made our launch a success.

Blog #5

2nd To Last Launch Day

Today we totally pulled together a brand new rocket, due to us forgetting our original prototype. A major change we did do though, was to add a bigger trash bag so that the surface area would be greater for our parachute, slowing down our rockets fall. Our rocket was in the air for a time of 6.08 seconds! That was our best time yet! Another factor of our success is that we added 800mL of water instead of the usual 500mL. We also increased the air pressure in the bottle. We do not know exactly how much psi was added because there was no pressure gauge, but we pumped it until it could not pump anymore. All we need to do now by Thursday is to figure a way to keep in in the air for another 4 seconds.

Blog #4

Aloha friends, this one of many videos of the best of our three launches this past friday. On the first launch, we tested the rocket with 750mL of water. Being that rocket only stayed airborne for three and a half seconds, we decided to experiment with the amount of water that we put inside the bottle. Kalamaku, Chelsey, and I tested the launch with 500mL of water in the bottle, and twenty or so pumps for pressure. Also, We placed a cone on the nose of the bottle for aerodynamics. The cone was made to come off being that our parachute (a plastic bag you can pick up at your local grocery store [purchase more than likely necessary]) was stuffed underneath it. To keep the cone and the bottle together, we taped fishing line to each of the objects thus making our project a whole lot safer. The cone didnt stay on. .... lol

Blog #3

Launch Day 2 (rocket w/ modification)
     Today we did a couple of launches. The first launch was exactly the same as yesterdays. It was the rocket with no modifications at all. The amount of water (500mL) and pressure (40psi) were the same as well. The time in the ayer was also the same as yesterday (4 seconds).
     The second launch of the day was with modifications. We added fins to the rocket. These fins (as seen on the video below) were as close to the nozzle of the bottle of possible. We think that doing this will help to add weight to the bottom as well has keep the rocket straight while in flight. The amount of water used was 500mL and the pressure was 40 psi. The time in the ayer with the fins was just about 4 seconds. I think these fins did not create much drag because they were small and did not protrude from the widest circumference of the bottle. The third launch with fins did not turn out as well as the first. The pressure and amount of water were the same as the other launches but the time in the ayer was 3.5 seconds.
    Tomorrow, Friday March 2, 2012, we will be launching our rockets with parachutes. Our plan for this modification is to place a cone shaped object(most likely a top of a soda bottle) on the rocket. It will be attached in a way where it stays on as it goes up but falls off when the rocket goes down. The parachute will be a plastic bag connected to strings (connected to the main section of the rocket) and will deploy when the cone falls off. Hopefully this simple plan will work as well as it sounds.
    Here is the video of our first launch with fins.

Blog #2

Launch Dia Uno con Chayse y Chelsey y Ku.

     Today, February 28, 2012, we executed a practice water rocket launch. For this launch we used a plain 2-liter soda bottle (in this case we used a diet Coca-Cola bottle). This bottle was not modified in any way, shape, or form. This launch mainly showed us how the water rocket launch system works and the proper safety procedures. This launch also allowed us to gather data such as "hang-time"(time in the ayer!).
    From this launch we discovered that our bottle, if filled with 500 mL of water and 40 psi of pressure, has a hang-time of approximately 4 seconds (4.01 sec to be very specific). We also discovered that the bottle went fairly straight immediately after the launch but flipped as it fell (flipped as in spun top over bottom). We think that adding a coned nose and fins at the bottom would help to solve this problem. We also think that adding weights disproportionally to the ends (nose and bottom, bottom being heavier) would help it to stay vertical as it falls. We also observed that the wind affects the flight of the bottle. The wind, at midday (between 12-1 'o clock), was blowing mauka to makai (or from Konia to the Auditorium). We recognized this and decided that launching the bottle as close to Konia as possible would compensate for the gusty wind.
    Thursday is launch day 2 and we will be modifying our rocket to hopefully improve it.
Here is a video from the first day of launch.

Blog #1

Bottle Rocket Plans.

          Welcome to the blog of Chayse, Chelsea, and Kalamakü. On this blog we will be discussing information about our water rocket.
          The Goal of this project is to get and keep the rocket in the air for at least 10 seconds. To make this project more competitive Mr. Blake said that the team with the longest hang time will get more points, thus getting a higher grade. So with this in mind we came up with our design plan.
          The first thing we need to do is get the rocket to go as high as we can. So we need it to be streamline. We need to turn the bumpy bottom of the bottle into an aerodynamic cone that will slice through the air. This will help us to maximize the amount of height our rocket will achieve.
          The second thing we need to do is to design/create an object that can help the rocket to slow its fall. The first thing that comes to mind is parachute...but to make it a more unique rocket we want to build some kind of horizontal fins to spin the bottle as it falls...sort of like a helicopter. We think that adding these fins will help our bottle fall slower. We combined the two ideas so that there is a parachute and also fins to make the rocket fall like a helicopter. Of course we know that the parachute lines will become twisted if the rocket spins as it falls so we can use a swivel...like the kind use for fishing lines.
         The third thing we need to do is attach fins to the base of the rocket in order to create spin while the rocket launches so that it flies in a straight line. This is important because going directly straight will help us to reach a higher hight...as opposed to it flying at an angle and not reaching its potential height.
         These are our ideas for this water rocket. We still have many adjustments to do to our plan to achieve maximum hang time.